A computer-implemented component broker series server for optimized caching of SQL data is implemented. In an object-oriented computer system, relational data from a relational database is cached in a data cache. The object-oriented computer system has a server that includes an instance manager and that is connected to at least one client. Objects that represent the relational data are created and managed under control of the instance manager. The relational data is stored in the data cache, which includes a virtual memory data cache for each client.

1. Field of the Invention
This invention relates in general to object server systems, and in particular to optimized caching of Structured Query Language (SQL) data in an object server system.
2. Description of Related Art
Object server computer systems are composed of collections of objects. Some object server computer systems use a relational database to store the data associated with one or more of the objects. The data in the relational database is retrieved from the relational database, manipulated, and stored in the relational database through use of an object interface to the relational database.
One of two approaches is typically taken to read and write data from the relational database. A first approach requires that a developer creating an object also generate read and write methods as part of the object implementation for reading or writing the data from and to the relational database. With the second approach, the object server computer system provides a function that performs the data read and write operations when the user describes, in a declarative manner, how the data attributes of the object map to the relational database.
One problem common to either approach is optimizing the movement of multiple objects to and from the relational database. Another problem common to either approach is determining when to lock the relational database so that updates that occur through the object interface are done with data integrity without performing excessive locking at the relational database. Excessive locking of data may degrade relational database concurrency. This is a particular concern with object-oriented computer systems where application programs tend to create long running transactions.
Yet another common problem is directed to providing a system in which relational data is represented by objects and which runs in a multi-threaded, multi-user object server environment.
Some computer systems that attempt to solve some of the problems mentioned above are: Sparky, which is written in SmallTalk by the International Business Machines (IBM) Object Technology Practices; Persistence, which is from Persistence Software; Java Relational Binding by O2 Technology; and DBConnect written jointly by IBM Santa Teresa Laboratory and Object Design, Inc. These computer systems map relational data to objects.
Some of the computer systems provide use of prefetch (i.e., preload options). Under a prefetch option, when data for an object is read from a relational database, data is also read for related objects for which there is a high likelihood of access. To read data for related objects, SQL SELECT and JOIN operations are used. The use of SQL SELECT and JOIN operations results in a more efficient access to a relational database than a series of individual SELECT statements to retrieve data for multiple objects.
Some of the computer systems implement pessimistic caching where data is read from the relational database during each transaction and the data remains locked in the relational database until the end of the transaction. If the data is needed by the next transaction, the data is reread from the relational database.
Other computer systems allow optimistic caching where data is unlocked at the relational database and remains in memory at the object server and can be reused by multiple transactions without rereading it from the relational database. A developer issues explicit refresh calls when the developer needs current data.
Some of the computer systems provide solutions that are designed to work in a client desktop environment where the client is connected directly to a relational database server. Other approaches make use of an object server (sometimes called tier 2 in a 3 tiered system) that is placed between the client and the relational database. This allows the object-oriented application program to execute at the object server and have a thin client.
Some of the approaches above do not track updated objects. When the object developer makes an update to an object, additional calls are required to apply the update to the relational database.
Moreover, when running in a multi-threaded, multi-user object server environment, the approaches above require that data be locked either at the database level or within the object server for serialization and data integrity. Use of such locks in a long running transaction can degrade system concurrency.
There is a need in the art for improved relational database access in a multi-threaded, multi-user object server environment.

Optimized caching of SQL data in an object server system

International Business Machines Corporation


A cooking apparatus and method for use of the same are disclosed that utilize forced convection and radiant heating cooking. In one embodiment, the cooking apparatus includes an oven housing defining a cooking chamber, a circulation chamber, and a catalyst chamber. The catalyst chamber is superposed to the circulation chamber and the circulation chamber is superposed to the cooking chamber. Heating elements are located in the cooking chamber and the circulation chamber. An airflow circulation loop is located between the cooking chamber and the circulation chamber. An exhaust airflow path is provided from the circulation chamber to the catalyst chamber to an exterior of the oven housing. A fan subassembly is located within the oven housing and the fan subassembly circulates convection air along the airflow circulation loop with a portion of the convection air being diverted into the exhaust airflow path.

Quickly prepared food products (often referred to as fast foods) are conventionally prepared on-site using various commercial cooking devices such as deep-fat fryers, grills, convection ovens, radiant heat ovens, rotisseries and the like. However, deep-fat frying and grilling raw meat on an open grill or pit is relatively dangerous since hot oils and fats are potential fire hazards and dangerous to personnel. Equipment for safely cooking such items typically requires a vented hood system which draws grease-laden vapor and smoke from the cooking equipment through filters and stainless steel ductwork to an external exhaust. Such vented hood systems usually include a fire extinguisher system and thus are expensive to install and maintain. Because of the increased risk of fire, operators of such systems generally incur expensive fire insurance premiums. Accordingly, operators of fast food restaurants, sports arenas, amusement parks and other operations which sell fast foods are always searching for better ways to cook food faster, cleaner, more safely, and less expensively.
Commercial food processors now offer many menu items (some partially cooked) which can be prepared for serving in a convection oven. Since these menu items are designed to be prepared either in an oven, in a deep-fat fryer or on a grill, they have been widely accepted and the quality and number of such products have improved and increased substantially. However, food products such as battered items (which are usually best when fried) and meats (which are usually best when grilled) suffer in quality when prepared in an ordinary convection oven. The fried-type products are often not as crisp as desired, and the ordinarily grilled items are not as juicy and tender as they would be if grilled. Although menu items such as French fries, chicken strips, hamburgers, etc., are highly desirable, many fast food operations do not offer such items because of the increased expense and risk associated with the equipment necessary to properly prepare them on-site. There is, therefore, an ever-increasing need for food preparation equipment which does not require use of hot oils or the like and which does not require hoods or other systems to control and remove vapors, etc., generated by the cooking process, but which can quickly and safely cook menu items which ordinarily require deep-fat frying or grilling.

Cooking apparatus and method for use of same


The purpose of this disclosure is to reduce viewer dissatisfaction caused by delays in communication, processing or the like in a system in which a server relays data reception and transmission between a terminal used by a distributor and a terminal used by a viewer. A command processing server which is connected to a command issuing terminal and a command executing terminal comprises: a reception unit which receives a command pertaining to a command execution terminal from a command issuing terminal; a notification unit which notifies the command execution terminal that a command has been received; and an execution instruction unit which transmits, to the command execution terminal, an instruction to execute a command on a command execution terminal, after the command execution terminal has been notified that a command has been received.

In recent years, there has been an extensive popularization of content providing services for streaming videos to various terminals such as personal computers, tablet terminals, portable terminals including smartphones, television receivers and game machines. The content providing service provides a service that allows a video viewer to post a comment such as a video impression as an example of a reaction to the video being viewed.
The content providing service distributes a video and comments posted by multiple viewers to terminals used by the viewers. The terminal superimposes and displays the comments on the distributed video. While watching the video, the viewers can enjoy comments exchanged with other users who watched the video.
In addition, it is possible to provide live broadcasting in which the server distributes a video data distributed from a terminal used by a distributor to a terminal used by the viewer in real-time. In such a content providing service, it is possible for the distributor and the viewer to share videos and comments in real-time. Further, in such a content providing service, the distributor may issue a command pertaining to the terminal owned by the viewer and lead the terminal owned by the viewer to execute the command through the server.
In general, in order to achieve a remote conference through a network, there is a system in which a first terminal participating in the remote conference sends materials to a second terminal participating in the remote conference, and the acquisition shows the notice of completion that the second terminal has received the materials (Patent Literature 1).
Patent Literature 1: Japanese Patent Publication No. 2017-68530

Command processing server, command processing program, command processing system, command execution program and command processing method


A firearm barrel preloading device can preload threaded connections. The preloading device can include an outwardly facing barrel-contact surface, an outwardly facing receiver-contact surface, non-planar surfaces between the barrel-contact surface and the receiver-contact surface. The non-planar surfaces can include mated pairs of axisymmetric surfaces that cooperate to spread apart the barrel-contact surface and the receiver-contact surface when the preloading device is moved toward an expanded configuration.

Conventional firearms often have interchangeable barrels for using different caliber ammunition. To install a barrel, a threaded end of a barrel can be threadably connected to a receiver. Significant forces need to be applied to the barrel to prevent motion between the barrel and the receiver that could adversely affect accuracy. For example, threaded receiver-barrel connections can often require preloading of approximately 100 pound-feet of torque. Barrel nuts can also be used to preload receiver-barrel connections. Unfortunately, specialized tools (e.g., barrel nut wrenches, clamps, etc.) are needed to remove barrels and then securely install another barrel in the receiver without damaging either the barrel or receiver. Additionally, some conventional barrel installations require drilling holes into the face of a receiver.

Firearm barrel pre-loading devices, connection assemblies, and firearms


A neural network based signal processor for a magnetic storage channel, such as a magnetic disk drive for a computer, uses a multiple layer perceptron neural network to perform the symbol sequencing detection, equalization and decoding of information signals retrieved from the magnetic storage medium.

1. Field of the Invention
The present invention relates to signal processors for processing information signals retrieved from a magnetic storage medium, and in particular, to neural network based signal processors for partial response maximum likelihood (PRML) read channels.
2. Description of the Related Art
Referring to FIG. 1, a conventional data storage and retrieval system which uses a magnetic disk includes a write channel and a read channel. Within the write channel, user data 9 is encoded by a data encoder 10 (e.g., with some form of run length limited code). The encoded data 11 is converted into a data symbol sequence by a data sequencer 12 (translating logic 0 bits to -1 and logic 1 bits to +1). The resulting data sequence 13 is stored on a magnetic disk 14d via the disk read/write electronics 14a, actuator arm 14b and read/write head 14c.
Within the read channel, the information signal 15 retrieved from the disk (via the read/write head 14c, actuator arm 14b and read/write circuit 14a) is filtered by a filter 16 and the filtered signal 17 is buffered by a gain controlled buffer amplifier 18. The buffered analog signal 19 is converted to a digital signal 21 by an analog-to-digital converter, or sampler, 20 and filtered by an equalizing filter 22. The equalized sample sequence 23 is used by a gain and timing control circuit 24 for controlling the gain of the buffer amplifier 18 via a gain control signal 25a and for controlling the sampler 20 via a sample control signal 25b. The equalized sample sequence 23 is also processed by a Viterbi detector 26 to determine the correct data sequence. This detected signal 27 is decoded by a data decoder 28 to provide the user data 29.
In such a conventional PRML read channel, a high sampling rate for the data is required to capture the signal samples, and with increasingly higher data retrieval rates such sample rates are now typically quite high. Accordingly, to keep up with such high speed data sampling, high speed hard wired digital signal processors (DSPs) must often be used.
Accordingly, it would be desirable to have a data read channel which avoids the need for high speed samplers and DSPs.

Neural network signal processor for magnetic storage channels


An apparatus and method for smart configuration of functional blocks within a semiconductor device is provided. A fuse array contains a plurality of fuses that are blown in manufacturing to enable/disable functional blocks on the semiconductor device. A control unit reads the state of the fuses, and logically merges the fuse states with a default configuration for the functional blocks. The result of the merge operation is stored in a feature control register that individually enables/disables the functional blocks. The control unit also receives a write command from an external source that modifies the feature control register, after the device is shipped from the manufacturer. The control unit selectively blocks writes to the feature control register that attempt to enable/disable functional blocks that should not modified.

1. Field of the Invention
This invention relates in general to the field of semiconductor device configuration, and more specifically to a method and apparatus that utilizes a smart fuse array on a semiconductor device to selectively enable/disable particular functional units on the device.
2. Description of the Related Art
A fuse is a circuit element with an initial structure that provides an electrical connection between two points, but which may be irreversibly destroyed thereby electrically disconnecting the two points. Fuses are sometimes used within integrated circuit devices to remove defective circuits from active operation, and to replace those defective circuits with good operable redundant circuits. Such fuses are typically fabricated in a conductive layer buried within a structure of a surrounding insulator material on the die of semiconductor device. A selected fuse is blown by directing a laser beam at the fuse, or by providing excessive electrical current to the fuse.
An example of a fuse 102 within a semiconductor circuit 100 is shown in FIG. 1. The fuse 102 is shown connected between a ground 104 and the source 106 of a FET 108. The FET 108 is configured to be "on". The source 106 is connected to a buffer 112 that is output to a particular functional block (not shown) to enable or disable the functional block. When the fuse 102 is intact, the source 106 is low, providing a logic low signal to the buffer 112. If the fuse 102 is blown, the source 106 goes high, creating a logic high signal to the buffer 112.
Thus, the circuit provides a permanent output from the buffer 112 that is either low or high, based on the condition of the fuse 102, intact or blown. The state of the fuse 102 is set at the time of manufacture, and is not modified at a later time.
To illustrate how the circuit 100 is used within a semiconductor device, reference is now made to FIG. 2. In FIG. 2, a memory device 200 is shown that includes a plurality of individually addressable memory cells 204. Also provided on the memory device 200 are a plurality of redundant memory cells 206. Each of the memory cells 206 are connected to fuse circuits 208. One skilled in the art should appreciate that not all of the memory cells 204 may be functional at the end of manufacturing. Therefore, after the device 200 has completed the manufacturing process, the memory cells 206 are tested to determine if any failures exist. Cells 210, 212 represent failed memory cells within the device 200. Fuses 208 attached to the redundant memory cells 206 on the rows associated with cells 210, 212 are blown to enable operation of those memory cells. Fuses are blown on rows where defective memory cells exist, thereby enabling associated redundant memory cells 206. Thus, by providing redundant memory cells 206, and fuse circuits 208 within the design of the device 200, defective memory cells may be selectively replaced before the device 200 is shipped to the customer. For a more complete background on the use of fuse circuits within a memory device, attention is directed to U.S. Pat. No. 5,548,555 to Lee et al., entitled METHOD AND CIRCUIT FOR REPAIRING DEFECT IN A SEMICONDUCTOR MEMORY DEVICE, the contents of which are hereby incorporated by reference.
One of the problems associated with utilizing fuse circuits to enable/disable particular functional blocks within a semiconductor device, whether a memory cell, or a complex circuit, is that once the state of the fuse is modified, i.e., by blowing the fuse, the effect on the semiconductor device is forever changed. Where fuses are used to replace defective memory cells with redundant memory cells, this is not a serious issue. However, when fuses are used to enable/disable more sophisticated functional blocks within a semiconductor device, the permanent "fused" condition is much more costly.
For example, if a fuse circuit were used to enable a floating point unit on a microprocessor, at the time of manufacture, a fuse would be blown (or left intact) to enable the FPU. All microprocessors manufactured at the same time would also have their FPU's enabled. If at some later point it was determined that the floating point unit was defective, there would be no way to disable the defective floating point unit. All of the microprocessors manufactured in that batch would have to be thrown away. This is very costly, not only for the original manufacturer, but also for all OEM's that maintained inventories of the microprocessor to build their products. One notorious example of a costly floating point unit problem required the manufacturer to provide a no questions asked replacement policy for all defective microprocessors.
Alternatively, if a particular functional block on a microprocessor is operational, but at the time of manufacture it is not desired to turn it "on", its associated fuse is blown, thereby permanently disabling the functional block. When a decision is made to turn the functional block on, currently manufactured microprocessors have their fuse left intact. However, for all of the microprocessors whose fuses are already blown, it is too late.
Moreover, as the number of functional blocks on semiconductor devices increase, so does the number of associated fuses. Requiring a one to one correspondence between functional blocks to be enabled/disabled and control fuses becomes costly, and takes up valuable die space.
What is needed is an apparatus that solves the above problems by providing an apparatus and method that allows functional blocks on semiconductor devices to be enabled/disable via a fuse array, but which also allows enablement of the functional blocks to be set to a predetermined default, or later modified through software.

Fuse array control for smart function enable


Disclosed are systems and methods for mechanically reclosing a hydraulically actuated sliding side door of a sleeve assembly. One sleeve assembly includes a housing defining one or more flow ports, a sliding sleeve arranged within the housing and movable between a closed position and an open position and back to the closed position, wherein, when in the closed position, the outer sleeve occludes the one or more flow ports, and, when in the open position, the one or more flow ports are exposed. A piston is movably arranged within a piston bore defined in the housing, and a locking mechanism is arranged within the piston bore and configured to engage the piston with the sliding sleeve, thereby allowing the piston to move the sliding sleeve to the open position.

The present invention relates to equipment utilized in subterranean well operations and, more particularly, to systems and methods for mechanically reclosing a hydraulically actuated sliding side door.
Hydrocarbon-producing wells are often stimulated by one or more hydraulic fracturing operations which generally include injecting a fracturing fluid into a subterranean formation penetrated by a wellbore at a hydraulic pressure sufficient to create or enhance at least one fracture therein. One of the purposes of the fracturing process is to increase formation conductivity so that the greatest possible quantity of hydrocarbons from the formation can be extracted/produced into the penetrating wellbore.
In some wells, it may be desirable to selectively create multiple fractures along a wellbore at predetermined distances apart from each other, thereby creating multiple "pay zones" from which hydrocarbons can be intelligently produced. A series of actuatable sleeve assemblies may be arranged within the downhole completion assembly in order to separate the pay zones for intelligent production. These sleeve assemblies have devices movably arranged therein generally known as sliding sleeves or sliding side doors due to the ability of the devices to shift an inner sleeve from a first position to a second position. Shifting these inner sleeves allow the operator at the surface to initiate hydrocarbon production, cease hydrocarbon production, or generally regulate hydrocarbon production through the sleeve assembly at that particular location.
Actuating a sleeve within the sleeve assembly serves to reveal one or more flow ports that, once exposed, allow the influx of fluids into the production tubing. In conventional actuated sleeve assemblies, the sleeve is not designed to retract into the closed position in order to close the flow ports and thereby cease hydrocarbon production at that location. Instead, a tool, such as a side door choke, is typically run into the sleeve assembly to occlude the flow ports and provide a permanent installation within the production tubing. While effective in sealing the flow ports and ceasing hydrocarbon production at that location, the side door choke adversely reduces the inner diameter of the production tubing at that location which, in turn, reduces the potential flow rate through the production tubing. A reduced inner diameter of the production tubing also adversely affects the size of the downhole tools that can be extended past the sleeve assembly, which are thereafter required to be of smaller diameters. Thus, there is a need for a reclosable sleeve assembly that does not disadvantageously reduce the inner diameter of the production tubing but nonetheless is effective in ceasing hydrocarbon production through the one or more flow ports.

Systems and methods for reclosing a sliding side door


An integrated granule product that includes a film having a plurality of ceramic coated granules bonded to the film by a cured adhesive. The integrated granule product is generally considered an intermediate product because it is suitable for application onto various substrates for end use applications such as roofing products and flooring products.

Roofing products are generally flat or sheet-like materials that can be arranged on a roof to prevent weather, e.g., wind, water, etc., from entering a roof structure. A roofing product can also serve to reflect heat energy from a roof. The roofing product should be durable enough to perform these functions for a number of years. Examples of roofing products include asphalt-based, wooden, or ceramic tile shingles.
Roofing products, particularly those which employ roofing granules, generally have been prepared from a water-proof, durable substrate having roofing granules disposed on a surface of the substrate. Asphalt-based roofing shingles, for example, typically comprise an asphalt-based substrate with roofing granules embedded into the asphalt. The roofing granules are generally colored to provide a desired aesthetic value upon application of the roofing product onto a building. These types of products are prepared by conventional practices generally recognized in the roofing products industry.
There is a continuing need in the roofing product art for new roofing product constructions, and for new processes for preparing roofing products. Conventional roofing products, such as shingles, are often susceptible to weather related damage that can either tear the base substrate or adversely affect the bond of the granule in the asphalt-based substrate. The release of the granules from the base permits the passing of light through to the asphalt. The light can degrade the asphalt and may cause premature failure of the roofing product.
The asphalt-based substrate can adversely affect the aesthetics of the coated granules applied onto the substrate. For example, lighter colored granules may darken upon application to the asphalt-based substrate. The darkening can be attributed to exposed black asphalt in gaps surrounding the granules. Additionally, the lighter color pigments may darken over time after application onto a roof due to the migration of the lower molecular weight materials from the asphalt onto the surface of the coated granules. The aesthetics of a roofing product can also be effected by the undesirable growth of algae on the exposed surface of the roofing product. Algae, growing on the exposed surface of the granules, may have direct access to the asphalt, which provides nutrients that can sustain growth.
It would be an advantage to provide a roofing product that is capable of withstanding severe weather conditions and capable of preventing the degradation of the underlying asphalt-based substrate. It would also be an advantage to provide a roofing product that prevents the discoloration of granules when applied onto an asphalt-based substrate.


The subject invention relates to antibodies to troponin I as well as methods of use thereof. In particular, such antibodies may be used to detect Troponin I in a patient and may also be used in the diagnosis of, for example, a myocardial infarction or acute coronary syndrome.

1. Field of the Invention
The subject invention relates to antibodies to troponin I as well as methods of use thereof.
2. Background Information
Troponin I is a muscle protein which may be used in the determination of myocardial damage subsequent to or during, for example, a myocardial infarction. In particular, troponin I is one of three subunits of the troponin complex which is located on the thin filament of the muscle contractile apparatus. This complex has a primary role in controlling the process of muscle contraction. The other two subunits (i.e., T and C) are also immobilized on the thin myofilaments with troponin I in cardiac as well as skeletal muscle tissue.
Assays have been described which measure cardiac troponin I in human serum. For example, a radioassay has been used for this purpose (Cummins et al., Am Heart Journal 113:1333-1344 (1987). However, the assay utilized polyclonal antibodies having significant cross-reactivity to skeletal forms of troponin I. Further, a sandwich assay has been utilized which uses two different monoclonal antibodies (Bodar et al., Clinical Chemistry 38:2203-2214 (1992); see also U.S. Pat. No. 7,285,418). Unfortunately, such assays have a very high degree of imprecision. Thus, the need certainly exists for immunoassays that are highly specific for and sensitive to troponin I. These immunoassays must also utilize antibodies which do not possess cross-reactivity to troponin I found in skeletal tissue. In particular, such immunoassays are needed so that appropriate therapy can be utilized by the treating physician thereby giving the affected patient the best possible prognosis.
All patents and publications referred to herein are hereby incorporated in their entirety by reference.

Antibodies to troponin I and methods of use thereof


A sprayer having a folding boom is disclosed which includes a main spray bar mounted at the rear end of a small vehicle or a trailer. First and second intermediate boom sections are pivotally connected, about horizontal axes, to the outer ends of the means spray bar and have wheels at the outer end thereof so that the intermediate boom sections will remain positioned above the ground regardless of the terrain encountered by the sprayer. First and second outer boom sections are pivotally mounted, about horizontal axes, to the outer ends of the intermediate boom sections. The outer boom sections may be folded onto the intermediate boom sections and when the outer boom sections are so folded, the spray nozzles thereon are rendered inoperative. The intermediate boom sections, with the outer boom sections folded thereon, may also be moved to a folded position relative to the vehicle. When the intermediate boom sections have been so folded, the spray nozzles thereon are rendered inoperative.

This invention relates to a sprayer and more particularly to a sprayer having boom sections at the outer end thereof which may be pivoted or folded with respect to the remainder of the spray boom.
Many types of sprayers have been previously provided for spraying fields, golf courses, yards, etc. The conventional sprayers normally include an elongated spray bar which extends transversely to the direction of movement of the vehicle pulling or supporting the sprayer. Many prior art devices have utilized folding boom sections for the sprayers to enable the sprayers to be positioned in either a field position or a transport position. However, when the folding boom sections of the conventional sprayers are positioned in the transport position, the non-folded spray boom section is incapable of being used. This is somewhat disadvantageous since it is frequently desirable to spray areas having a width less than the full width of the spray bar.
It is therefore a principal object of the invention to provide an improved sprayer.
A further object of the invention is to provide a sprayer having pivotal or folding boom sections at the outer end thereof with means being provided to render the spray nozzles on the boom sections inoperative when the boom sections are in their folded condition.
Yet another object of the invention is to provide a sprayer having folding boom sections wherein the boom sections are quickly and easily folded from an operative position to a folded positions and vice-versa.
Yet another object of the invention is to provide a sprayer which permits the sprayer to be used on irregular terrain such as commonly experienced in spraying golf courses having hills, mogules, etc.
These and other objects of the invention will be apparent to those skilled in the art.


A semiconductor package is disclosed. The package includes a leadframe having drain, source and gate leads, a semiconductor die coupled to the leadframe, the semiconductor die having a plurality of metalized source areas and a metalized gate area, a patterned source connection having a plurality of dimples formed thereon coupling the source lead to the semiconductor die metalized source areas, a patterned gate connection having a dimple formed thereon coupling the gate lead to the semiconductor die metalized gate area, a semiconductor die drain area coupled to the drain lead, and an encapsulant covering at least a portion of the semiconductor die and drain, source and gate leads.

The present invention generally relates to a semiconductor package and more particularly to a semiconductor package having a bridged plate connecting a power semiconductor device source metalized contact and a leadframe source lead.
Semiconductor devices are conventionally connected to leadframe leads using either plate interconnections or wire bonding. For example, U.S. Pat. No. 5,821,611 discloses a semiconductor device which comprises a first lead having a tip formed with an island, a semiconductor chip unit mounted on the island of the first lead by means of a solder layer and having a plurality of electrode bumps projecting away from the island, and a plurality of additional leads each of which has a tip electrically connected to the electrode bumps via respective solder deposits. The additional leads include at least second and third leads. The leads are alloyed to the electrode bumps in a heating furnace and the solder bumps may spread during heating and create undesirable shapes.
U.S. Pat. No. 6,040,626 discloses a semiconductor package which employs a mixed connection between a MOSFET top surface comprising a low resistance plate portion for connecting to a source and a wire bond for connecting to a gate. Wire bonding may introduce short circuits in the device due to device dielectric layer damage during the wire bonding process.
A semiconductor package with directly connected leads is disclosed in U.S. Pat. No. 6,249,041. A semiconductor device includes a semiconductor chip with contact areas on the top or bottom surface. A first lead assembly, formed from a semi-rigid sheet of conductive material, has a lead assembly contact attached to one of the contact areas of the semiconductor chip. The first lead assembly also has at least one lead connected to and extending from the lead assembly contact. A second lead assembly, also formed from a semi-rigid sheet of conductive material, has a lead assembly contact attached to another one of the contact areas of the semiconductor chip. The second lead assembly also has at least one lead connected to and extending from the lead assembly contact. An encapsulant encloses the semiconductor chip, the lead assembly contact of the first lead assembly and the lead assembly contact of the second lead assembly. The semiconductor device has low electrical and thermal resistance contributions from the package due to the direct connection of the lead assemblies to the chip. The lead assembly contact areas are held in contact with lead contact areas on the semiconductor chip by an electrically conductive adhesive layer. The electrically conductive adhesive layer may be a silver-filled epoxy or polyimide paste or solder bumps. The adhesive layer may be cured in a curing oven, if necessary. The adhesive layer does not include soft solder or solder paste.
Another semiconductor package with directly connected leads is disclosed in U.S. Pat. No. 6,479,888. A MOSFET comprises a plurality of inner leads electrically connected to a surface electrode of a semiconductor pellet having a field effect transistor on a principal surface thereof. The inner leads are mechanically and electrically connected to the principal surface by a gate connecting portion and source connecting portions constituted by bumps.
A common problem encountered in the use of patterned plate or clip interconnections is that the plates or clips may float during solder reflow and result in a misaligned interconnection. In some cases, the misalignment results in a short circuit between the source and gate contact areas resulting in low assembly yields. Furthermore, it is difficult to control the required solder volume to prevent this problem.
Another problem resulting from the use of patterned plate or clip interconnections is the thermal expansion mismatch between the silicon of the semiconductor device and the metal of the patterned plate or clip. The larger the contact area of the patterned plate or clip, the higher the stress induced by the mismatch, which often results in die cracking. To reduce the stress, a smaller plate or clip may be used. However, the smaller contact area may result in higher resistance.
There is therefore a need in the art for a semiconductor package that includes a semiconductor power device connected to leadframe source and gate leadframe contact areas by means of patterned plates that overcomes the problems of the prior art. There is also a need for a patterned plate interconnection that does not float during solder reflow and ensures precise clip placement and location assurance. There is also a need for a semiconductor package having device metallized areas for restricting the flow of solder during the soldering process. There is also a need for a metalized area formed of Ni/Au. There is also a need for a semiconductor package process that increases throughput and provides easier assembly process control. There is also a need for a semiconductor package method that provides a soft attachment process of the patterned plates onto the semiconductor power device. There is also a need for a semiconductor package having an exposed source plate. There is also a need for a semiconductor package having reduced electrical resistance. There is a further need for a semiconductor package having improved thermal dissipation properties. There is also a need for a semiconductor package having improved mechanical properties.

Semiconductor package having a bridge plate connection

Alpha and Omega Semiconductor Incorporated


A semiconductor memory device is disclosed having a layout including, alternating pluralities of memory cell arrays and word line driving blocks arranged next to alternating pluralities of sense amplifier blocks and conjunction blocks, such that each sense amplifier block is located lateral to a corresponding memory cell array, and each conjunction block is located lateral to a corresponding word line driving block. Each sense amplifier block alternately includes one of a supply voltage driver and a ground voltage driver.

1. Field of the Invention
Embodiments of the invention relate to a layout for a semiconductor memory device. More particularly, embodiments of the invention relate to a layout for distributed sense amplifier drivers adapted for use in a semiconductor memory device.
This application claims priority to Korean Patent Application No. 10-2005-0064756 filed on Jul. 18, 2005, the subject matter of which is incorporated by reference in its entirety.
2. Description of the Related Art
FIG. 1 is a circuit diagram illustrating a conventional bit line sense amplifier 100 and drivers 110 and 120. Referring to FIG. 1, bit line sense amplifier 100 is connected to a bit line BL and a complementary bit line BLB which are in turn connected to memory cells (not shown). Bit line sense amplifier 100 includes NMOS transistors 101 and 102 which are connected in series between the bit line BL and the complementary bit line BLB. The gate and drain of NMOS transistor 101 are respectively connected to the bit lines BLB and BL, and the gate and drain of NMOS transistor 102 are respectively connected to the bit lines BL and BLB. The sources of NMOS transistors 101 and 102 are connected to a ground voltage driver 110. Ground voltage driver 110 is an NMOS transistor having a gate connected to a first driving signal LAN and a source connected to a ground voltage VSS.
Bit line sense amplifier 100 further includes PMOS transistors 104 and 105 which are connected in series between the bit line BL and the complementary bit line BLB. The gate and drain of PMOS transistor 104 are respectively connected to the bit lines BLB and BL, and the gate and drain of PMOS transistor 105 are respectively connected to the bit lines BL and BLB. The sources of PMOS transistors 104 and 105 are connected to a supply voltage driver 120. Supply voltage driver 120 is a PMOS transistor having a gate connected to a second driving signal LAP and a source connected to a supply voltage VDD.
Bit line sense amplifier 100 and respective drivers 110 and 120 may be arranged in a semiconductor memory device, such as a dynamic random access memory (DRAM), as illustrated in the layout diagrams of FIGS. 2, 3, or 4.
Referring to FIG. 2, each one of a plurality of memory cell array blocks MCA includes a plurality of memory cells arranged in a matrix, a plurality of sense amplifier blocks SA respectively connected to bit lines associated with the memory cell array blocks MCA, and a plurality of word line driving blocks SWD respectively connected to word lines associated with the memory cell array blocks MCA. In addition, a conjunction block CONJ is located between respective sense amplifier blocks SA and associated word line driving blocks SWD.
Each sense amplifier block SA includes a plurality of the bit line sense amplifiers 100, like one illustrated in FIG. 1. In each conjunction block CONJ, sense amplifier drivers, (e.g., supply voltage driver 120 and ground voltage driver 110 of FIG. 1) are arranged in an alternating manner. An N-well region is formed to pass through the conjunction blocks CONJ having supply voltage driver 120, and through the sense amplifier blocks SA having PMOS transistors 104 and 105 of bit line sense amplifier 100.
Referring to FIG. 3, ground voltage driver 110, which is included in every other conjunction block CONJ in FIG. 2, is instead included in each sense amplifier block SA. That is, ground voltage driver 110 is divided into several constituent parts and arranged in each sense amplifier block SA, to thereby increase the driving efficiency of each bit line sense amplifier 100.
Referring to FIG. 4, supply voltage driver 120, which was included in each conjunction block CONJ in FIG. 3, is instead included together with ground voltage driver 110 in each sense amplifier block SA. Each supply voltage driver 120 and ground voltage driver 110 is divided into several constituent parts and arranged in the sense amplifier block SA, to thereby increase driving efficiency of each bit line sense amplifier 100.
However, when both supply voltage driver 120 and ground voltage driver 110 are included in a sense amplifier block SA, it is difficult to conform to the tolerances established by contemporary manufacturing design rules. More particularly, it is very difficult to maintain defined margins between an N-well region for the PMOS transistor of supply voltage driver 120 and an N-active region for the NMOS transistor of ground voltage driver 110. As a result, it is difficult to manufacture the desired sense amplifier block SA illustrated in FIG. 4, for example. In order to obtain this desired sense amplifier block SA it must be expanded in its constituent area in order to obtain the necessary manufacturing margin. This expansion causes an undesirable increase in the overall chip size.
Accordingly, there is a need for an arrangement of sense amplifier drivers having increased driving efficiencies that provides a required manufacturing margin without increasing the overall chip size.

Layout for distributed sense amplifier driver in memory device


The present invention allows detection of an exposure time of an image that has already been captured. A motion detector 102 detects an amount of inter-frame movement of a foreground object in a designated frame based on the designated frame and a frame preceding or subsequent to the designated frame. A mixture-ratio calculator 104 detects a mixture ratio indicating the ratio of mixture of a foreground component and a background component in a mixed area of the designated frame. In accordance with the mixture ratio, the mixture-ratio calculator 104 detects the amount of movement of the foreground object within an exposure time in which pixel data is obtained. A shutter-time calculator 106 detects a ratio of a time interval between frames to the exposure time based on the amount of inter-frame movement and the amount of movement within the exposure time of the foreground object. The present invention is applicable to an image processing apparatus.

A technique for detecting incidents occurring in the real world by a sensor and for processing sampled data output from the image sensor have been widely used.
For example, motion blur occurs in an image obtained by capturing an object moving in front of a predetermined stationary background with a video camera if the moving speed is relatively high.
However, it has not hitherto been allowed to detect a shutter time of an image that has already been captured.

Image processing apparatus and method, and image pickup apparatus


A method and apparatus for mounting a toilet seat hinge to a toilet pan uses an adhesive. The adhesivised surface of the hinge is held clear of the pan until correct positioning is established. Thereafter the adhesivised surface is displaced directly into contact with the pan.

A toilet seat is typically fixed to a toilet pan by way of two spaced hinges fixed to spaced positions on or adjacent to the rear edge of the seat. One part of each hinge is secured to the seat and the other part of each hinge is secured to the pan. That part of the hinge attached to the pan is typically fixed by passing a threaded rod or shaft through a vertical hole extending downwards from the top face of the pan, and then applying a locking nut to that part of the rod or shaft that projects from the opposite end of the hole.
A problem that arises from this arrangement is that the holes in the pan are invariably larger in diameter than the diameters of the fixing rods or shafts and, over time and while being subjected to working loads, the rods displace relative to the axes of the holes in the pan, the locking nuts work loose and the toilet seat thus moves with respect to the pan.
Various methods have been adopted, in the past, to reduce the problem. One common method involves positioning rubber or plastics washers between the hinges and the pan but this solution has limited effectiveness for a number of reasons. Firstly the materials from which the washers are formed deteriorate with time. Further, they deteriorate with exposure to a number of toilet cleaning chemicals. Thirdly toilet pans are generally formed from vitreous enamel which has a very smooth, low friction surface. As a result, once tension on the fixing rods lessens, the washers can slide freely over the surface of the pan.
It is an object of the disclosure to provide a method and apparatus which will go at least some way in addressing the drawbacks mentioned above; or which will at least provide a novel and useful alternative.

Mounting method and/or apparatus for mounting a toilet seat


Systems and methods for soft buffer handling with limited memory access bandwidth are provided herein. In some embodiments, a method of operation of a User Equipment (UE) of a cellular communications network includes receiving a retransmission that would require a total number of memory accesses to process that is greater than a memory access bandwidth of a soft buffer of the UE. The method also includes prioritizing which bits should be read from or written to the soft buffer of the UE when processing the retransmission based on the memory access bandwidth, any previously received redundancy versions, and/or a currently received redundancy version. According to some embodiments, this achieves higher system performance than Chase Combining alone while keeping the receiver implementation limitation as low as alternative solutions.

Long Term Evolution (LTE) cellular communications systems use Orthogonal Frequency-Division Multiplexing (OFDM) in the downlink and Discrete Fourier Transform (DFT)-spread OFDM in the uplink. The basic LTE downlink physical resource can thus be seen as a time-frequency grid as illustrated in FIG. 1, where each resource element corresponds to one OFDM subcarrier during one OFDM symbol interval.
In the time domain, LTE downlink transmissions are organized into radio frames of 10 ms, as shown in FIG. 2, each radio frame consisting of ten equally-sized subframes of length Tsubframe=1 ms.
In LTE transmission using a single spatial layer, one transport block is transmitted to the receiver. When multiple spatial layers are used (such as Multiple Input Multiple Output (MIMO) transmission), two transport blocks are transmitted to the receiver. Since a transport block can be very large (e.g., up to 97896 bits for single spatial layer), a large transport block is divided into a number of code blocks that have suitable sizes for turbo encoding and decoding. For example, the transport block of size 97896 bits is divided into 16 code blocks of size 6144 bits each (including Cyclic Redundancy Check (CRC) bits per LTE specs TS 36.212).
In LTE systems, Hybrid Automatic Retransmission Request (HARQ) protocol is used to enhance transmission reliability. When an initial transmission is not received correctly by the receiver, the receiver stores the received signal in a soft buffer (implemented in a soft buffer memory, where "soft buffer memory" is physical/hardware memory utilized for the soft buffer) and signals to the transmitter of such unsuccessful transmission as illustrated in FIG. 3. The transmitter can then retransmit the information (referred to as the transport block in LTE specs) using the same channel coded bits or different channel coded bits. The receiver can then combine the retransmission signal with that stored in the soft buffer. Such combining of signals greatly enhances the reliability of the transmission. Incorrectly received coded data blocks may be stored as "soft bits" or soft values. These soft bits indicate what the receiver hypothesizes that the bit is and how certain the receiver is that this is a correct hypothesis. These soft bits can be combined with the retransmitted bits to calculate a more accurate hypothesis. These soft bits are stored in a soft buffer at the User Equipment (UE)/receiver so that, when the retransmitted block is received, the received values for the two blocks may be combined. Depending on the implementation, the receiver is only able to perform a certain number of soft bit reads from the soft buffer and soft bit writes to the soft buffer. As used herein, the total number of reads and writes that the receiver is capable of performing in the allotted time is referred to as the memory access bandwidth.
In the LTE system, the data transmission is protected by a rate 1/3 turbo code. To simplify signaling and operation complexity, a conceptual model referred to as a circular buffer is used in the LTE HARQ operations. This circular buffer model is illustrated in FIG. 4 for the case of single spatial layer transmission. The buffer consists of 32 columns of systematic bits followed by 64 columns of parity bits generated by the turbo encoder. The number of rows depends on the size of the transport block to be transmitted.
To simplify the signaling of what bits are transmitted to the receiver, four redundancy versions are defined. Each redundancy version is defined as the bits that can be read out of the circular buffer column-by-column starting from the head of a specific column in the circular buffer. The starting points of the four Redundancy Versions (RV): RV=0, 1, 2 and 3 are the heads of columns #2, #26, #50, and #74 (note the numbering of columns starts from 0). For a transmission using a specific redundancy version, the transmitter reads the bits starting from the start of the redundancy version until the necessary number of bits is obtained. If the reading reaches the end of the buffer and still more bits are needed, the reading of bits then resumes from the beginning of the buffer.
In the case of multi-spatial layer transmission, two transport blocks are transmitted in LTE. The circular buffer size is cut in half by discarding part of the parity bits. More specifically, the circular buffer model for LTE is illustrated in FIG. 5 for the case of multi-spatial layer transmission. In this case, the buffer consists of 32 columns of systematic bits followed by 16 columns of parity bits generated by the turbo encoder. The starting points of the four redundancy versions RV=0, 1, 2 and 3 are the heads of columns #2, #14, #26 and #38 (note the numbering of columns starts from 0).
It can be appreciated by one skilled in the art that it is generally advantageous to perform retransmission that carries more bits that have not been transmitted in previous transmission attempts. For instance, in a so-called Chase Combining protocol, the transmitter sends the initial transmission using RV=0 and resends subsequent retransmissions also using RV=0. That is, in Chase Combining, every retransmission contains the same information (data and parity bits). The receiver uses maximum-ratio combining to combine the received bits with the same bits from previous transmissions. Because all transmissions are identical, Chase Combining can be seen as additional repetition coding. That is, every retransmission adds extra energy to the received transmission through an increased Eb/N0 (the energy per bit to noise power spectral density ratio).
Such a simple HARQ protocol as Chase Combining mostly provides benefits from combining the signal energy from the transmissions resulting in, for example, a 3 dB gain for 2 transmissions and 4.8 dB for 3 transmissions. On the other hand, in a so-called Incremental Redundancy protocol, the transmitter picks a redundancy version that shares the lowest number of bits, such as the redundancy version that was used in the initial transmissions. That is, when using Incremental Redundancy, every retransmission contains different information than the previous transmission. Multiple sets of coded bits are generated, each representing the same set of information bits. The retransmission typically uses a different set of coded bits than the previous transmission, with different redundancy versions generated by puncturing the encoder output. Thus, at every retransmission the receiver gains extra information. This HARQ protocol provides both the energy gain as well as additional coding gains. Using the highest rate transmission using 256 Quadrature Amplitude Modulation (QAM) as an example, 8.4 decibel (dB) gains can be obtained after two transmissions, and 11.3 dB gains can be obtained after three transmissions.
The LTE Rel-10 standard supports bandwidths larger than 20 megahertz (MHz). One important requirement on LTE Rel-10 is to assure backward compatibility with LTE Rel-8. This should also include spectrum compatibility. That would imply that an LTE Rel-10 carrier wider than 20 MHz should appear as a number of LTE carriers to an LTE Rel-8 terminal. Each such carrier can be referred to as a Component Carrier (CC). In particular for early LTE Rel-10 deployments, it can be expected that there will be a smaller number of LTE Rel-10-capable terminals compared to many LTE legacy terminals. Therefore, it is necessary to ensure an efficient use of a wide carrier also for legacy terminals, i.e. that it is possible to implement carriers where legacy terminals can be scheduled in all parts of the wideband LTE Rel-10 carrier. The straightforward way to obtain this would be by means of Carrier Aggregation (CA). CA implies that an LTE Rel-10 terminal can receive multiple CCs, where the CCs have, or at least could possibly have, the same structure as a Rel-8 carrier. CA is illustrated in FIG. 6. A CA-capable UE is assigned a Primary Cell (PCell) which is always activated, and one or more Secondary Cells (SCells) which may be activated or deactivated dynamically.
In Rel-13, LAA (Licensed-Assisted Access) has attracted a lot of interest in extending the LTE carrier aggregation feature towards capturing the full breadth of opportunities of unlicensed spectrum in the 5 GHz band. A Wireless Local Area Network (WLAN) operating in the 5 gigahertz (GHz) band nowadays already supports 80 MHz in the field, and 160 MHz is to follow in Wave 2 deployment of Institute of Electrical and Electronics Engineers (IEEE) 802.11ac. There are also other frequency bands, such as 3.5 GHz, where aggregation of more than one carrier on the same band is possible, in addition to the bands already widely in use for LTE. Enabling the utilization of bandwidths for LTE in combination with LAA similar to bandwidths used for IEEE 802.11ac Wave 2 will lead to proposals for extending the carrier aggregation framework to support more than five carriers. The extension of the CA framework beyond five carriers was approved to be one work item for LTE Rel-13. The objective is to support up to thirty two carriers in both Uplink (UL) and Downlink (DL).
To support up to 32 carriers in DL, the Uplink Control Information (UCI) feedback, e.g. HARQ-ACK bits, will increase significantly. For each DL subframe, there are 1 or 2 HARQ-ACK bits per carrier depending on whether spatial multiplexing is supported or not. Hence, for Frequency-Division Duplex (FDD), there can be up to 64 HARQ-ACK bits if there are 32 DL carriers. The number of HARQ-ACK bits for Time-Division Duplex (TDD) is even larger, potentially as high as hundreds of bits depending on the TDD configuration. Therefore, a new Physical Uplink Control Channel (PUCCH) format(s) supporting larger payload is necessary. Similarly, the piggyback of the increased number of UCI bits also motivates the enhancements on UCI feedback on Physical Uplink Shared Channel (PUSCH).
In the LTE specification, each UE is required to store a specific number of received soft bits in its soft buffer. To support high data rate communications, high read and write bandwidths are needed for such soft buffer to and from the baseband processor and the turbo decoder. It has hence been a general practice to incorporate the soft buffer in the same chip with the baseband processor and the turbo decoder.
It has been suggested that the traditional solution of collocating the soft buffer and the baseband processor may not be an economically viable or even technically feasible solution for supporting a large number of carriers. It has further been suggested to adopt off-chip memory. Such a solution would have only limited bandwidth to read and write the soft bits.
Using the single-spatial layer transmission case as a non-limiting example, a receiver will store the soft bits corresponding to RV=0 in the off-chip soft buffer. The bandwidth issue is most limiting when the transmission is using the highest order modulation and the highest coding rate allowed in the LTE specs. This corresponds to 256 QAM Modulation and Coding Scheme (MCS) 27 with code rate r=0.9035. At such code rate, approximately [32/0.9035]=36 columns of soft bits are stored to the soft buffer. When a retransmission using the same RV=0 is received by the receiver, the receiver shall read out the previously stored soft bits and combine them with the newly received soft bits for decoding. If the decoding still fails, the receiver shall write the combined soft bits back to the soft buffer.
As illustrated in FIG. 7, the receiver hardware shall be designed to support enough soft buffer access bandwidth to accomplish the following two sets memory read-writes when the highest order modulation and the highest coding rate are used in the transmissions:                36 cols (#2-#37) read from memory to combine with new soft bits        After decoding fails, 36 cols (#2-#37) of new combined soft bits are written back to memory
This memory access bandwidth is proportional to read-writes of 72 columns per turbo code block for the highest MCS transmission. For a receiver designed to just meet such a minimum memory access bandwidth requirement, it may not be able to read the entirety of the stored soft bits from the off-chip memory for soft combining such as those illustrated in FIG. 8 for the single-spatial layer transmission case where two retransmissions fail. Such situation requires memory access bandwidth proportional to read-writes of 108 columns per turbo code block for the highest MCS transmission, which is higher than the designed bandwidth proportional to read-writes of 72 columns.
Further consider the case of multi-spatial layer transmission where two transport blocks are transmitted. For each code block for each transport block, the memory access bandwidth is proportional to read-writes of 72 columns per turbo code block for the highest MCS transmission as illustrated in FIG. 9. Since the two transport blocks may both fail, the receiver should be designed to support memory access bandwidth proportional to read-writes of 2×72=144 columns per turbo code block for the highest MCS transmission.
Similarly, in the case of multi-spatial layer transmission illustrated in FIG. 10 where two retransmissions fail, the required memory access bandwidth is proportional to read-writes of 2×84=168 columns per turbo code block for the highest MCS transmission, which is higher than the designed bandwidth proportional to read-writes of 144 columns.
To overcome such bandwidth limitation, it has been suggested to restrict the HARQ protocol operations to using mostly the same redundancy version as the initial transmissions (i.e., the Chase Combining protocol). However, such a solution severely limits the system performance, as there are large performance differences between Chase Combining and Incremental Redundancy protocols as discussed above. As such, systems and methods are needed for soft buffer handling with limited memory access bandwidth.

Soft buffer handling with limited memory access bandwidth


The present inventors show that cannibal cells can undergo senescence after entosis in vivo and that the tumor suppressive protein p53 act as a repressor of this phenomenon. They therefore propose new tools to study the molecular pathways involved in the cannibalism process, for example by measuring the expression levels of p53 or splice variants thereof (such as Δ133TP53, TP53β, TP53γ or Δ40TP53), the release of extracellular ATP or purinergic P2Y2 receptor activity. The present inventors also demonstrated that the detection of senescent cannibal cells in breast adenocarcinoma obtained from patients treated with neo-adjuvant therapy positively correlates with good patient's response to treatment. Altogether, these results provide the first evidence that detection of cellular cannibalism and senescence simultaneously in tumors helps for the diagnosis of disease outcomes and for the prediction of treatment efficiency against cancer diseases.

Cannibalism constitutes a consumption strategy used by micro- and higher organisms to adapt to environmental stresses and to survive. Gram positive species, Bacillus subtilis and Streptococcus pneumonia exert cannibalistic activities during the early stages of sporulation (Gonzalez-Pastor et al., Science 2003) or during natural genetic transformation (Guiral et al., PNAS 2005). In contrast, the slime molde Dictyostelium caveatum represses its predatory abilities during its quasi-multicellular differentiation stage (Waddell and Duffy, The Journal of cell biology 1986). In Drosophila, studies on genetic mosaics that place cells in competition within tissues unrevealed that cannibalism is a genetically controlled process that may occur at the single cell level and actively participates to cell competition during tissue repair and tumor development (Li and Baker, Cell 2007). Although cellular cannibalism is poorly reported in physiological situations, cannibal cells have been frequently detected in various human tumor types such as melanoma, leukemia and cervical carcinoma, colon carcinoma, stomach carcinoma, liver carcinoma adenocarcinoma and in metastatic breast carcinoma (Overholtzer and Brugge, Nature reviews Molecular cell biology 2008).
On a one hand, cellular cannibalism was suggested to cause the destruction of cancer cells by other malignant cells by entosis. In contrast to oilier (apoptotic, necrotic or autophagic) cell death forms that are controlled in a cell-autonomous fashion, entosis (from the Greek word entos, which means inside, into, or within) requires the internalization of a live target cancer cell by a live <<cannibal >> cancer cell (Overholtzer and Brugge, Nature reviews Molecular cell biology 2008). An inverse correlation between entosis and metastasis appearance in human pancreatic adenocarcinoma was furthermore reported, suggesting that this atypical death process may represent intrinsic tumor suppression mechanism (Cana et al., EMBO Mol Med. 2012).
On another hand, cellular cannibalism was shown to provoke the polyploidization of the engulfing cell by disrupting cytokinesis, and hence to promote oncogenesis indirectly, by generating polyploid cells that tend to generate aneuploidy daughter cells (Krajcovic et al., Nat. Cell Biol. 2011; Krajcovic and Overholtzer, Cancer Res. 2012).
As a consequence of (homotypic or heterotypic) interactions between cancer cells or between cancer cells and other (stromal or immune) cells, cannibalism could have—depending on the genetic status of cancer cells (target and cannibal cells) and on tumor microenvironment—variable consequences on tumor growth and disease outcomes.
Although the "cell-in-cell" cytological features have been widely reported in human tumors, the molecular and cellular bases of cellular cannibalism remain unknown.
In this context, the present inventors provide evidence that TP53 and, more specifically, Δ133TP53, acts as repressors of cellular cannibalism. Their results also unrevealed that cellular cannibalism is functionally connected to senescence, both in vitro (in cellular models of senescence) and in vivo (in human breast carcinoma), where they may influence the efficiency of a chemotherapeutic treatment.

Simultaneous detection of cannibalism and senescence as prognostic marker for cancer


Methods of diagnosing peripheral nerve damage, including diagnosing and monitoring chronic back and cervical pain are disclosed. The methods involve subjecting a body fluid sample from a patient suspected of having chronic lumbar or cervical pain and peripheral nerve damage to two-dimensional electrophoresis or an immunoassay and measuring relative amounts of protein or proteins which increase or decrease in concentration as compared to a standard control. A preferred method employs an Apo-E variant as a marker of peripheral nerve damage. Also disclosed are kits for use with the diagnostic methods.

Conditions which cause pain are obviously very prevalent in medicine. Very often, the cause of the pain is apparent. However, frequently, the physiological cause of the pain is not known. It is, of course, important to the clinician to determine the cause of the pain, so that proper treatment can be instituted. Prime examples of painful conditions wherein it is difficult to determine the cause of the pain are in patients experiencing spinal pain (i.e., lumbar, thoracic and cervical), particularly lower back ache or neck pain, and more particularly chronic cases. It is crucial in these conditions to determine whether they are caused by muscle or fibrous tissue injury, or are actually a result of nerve damage. The proper determination of the etiology will guide the clinician in the proper form of treatment.
Eighty-five percent of the United States population, at one time or another, seek medical consultation for back ache, particularly chronic back ache. Over 40 million people claim disability due to chronic back pain (or low back syndrome) and the medical costs alone to care for this group is over 40 billion dollars [Aronoff, G.M., Evaluation and Treatment of Chronic Pain, Urban and Schwarzenberg, Baltimore (1985)]. This does not include the enormous socio-economic loss, estimated to be in the trillions of dollars. In 1985, 2.7 million individuals received social security disability insurance at a overall cost of $18.9 billion [Social Security Administration, Report of the Commission on Evaluation of Pain, Washington D.C. , Department of Health and Human Services (1986)].
Clinically, chronic pain, as opposed to acute pain, is continuous pain which persists for six months or more. Pain has been defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage [International Association for the Study of Pain, chaired by Mersky (1979)]. Vasudevan has noted that there are several aspects to pain: nociception (the perception of pain, a physical stimulus); interpretation of the stimuli as "painful"; and the evaluation of the pain as creating suffering. [Vasudevan et al., "Counseling the Patient with Chronic Pain--The Role of the Physician" , In Persistent Pain, Kluwer Academic Publishers Boston (1988)].
In the present state of the art, there is no objective, accurate test for spinal pain, particularly chronic lower back (or lumbar) pain (hereinafter referred to as "CLP" which stands for "chronic lumbar pain") and/or radiating pain, and chronic cervical (neck) pain (hereinafter referred to as "CCP" which stands for "chronic cervical pain"). More specifically, there is no protein-based clinical test which quantitatively detects the presence or absence of CLP or CCP, much less one having the capability to quantitate or monitor the progression or regression of CLP or CCP. The existence of such a test would be of infinite value to the patient, the doctor, and the society which bears the cost-burden of this problem (i.e., insurance companies and government health and social security departments). An objective test for CCP or CLP would allow for the following:
1. Verify the presence or absence of the syndromes of CCP or CLP based on an organic cause. Ideally, this test would be performed on the first visit so that a baseline could be established to take advantage of the quantitative aspects of the test. If no organic cause existed, according to the test, then it would not be necessary to proceed with the more costly examinations (e.g., MRI's, CT scans, myelograms, discograms, bone scans, electromyelograms, and consultations) which are, in the present state of the art, required to rule out causes for this syndrome. If an organic cause is determined to exist, then the routine work-up could proceed with high expectations for success. At this point, if the routine tests for CLP or CCP are negative and the protein-based analysis disclosed herein is positive for back syndrome, then the treating physician would be justified in continuing to seek a correctable, organic cause. PA1 2. Monitor the progress and effectiveness of treatment. All chronic back or cervical syndromes are treated conservatively, initially. The effect of this treatment could be assayed and one or more of the following judgments could be made: continue with an improving test; discontinue with a worsening test; change treatment with a worsening test; recommend initial or revision surgery only when the test was worsening or not showing any improvement. Thus, an objective, biochemical test would increase the efficiency of conservative patient management and eliminate any unnecessary surgery. It is foreseeable that the test disclosed herein would become the standard for assessment, wherein surgery would be indicated only if the protein analysis indicated it. PA1 3. Identify the point of maximal medical improvement. By periodically administering the test during a course of treatment, the quantitative characteristic of the test would allow the physician to assess the degree of the symptoms of peripheral nerve damage of backache and/or radiating pain (particularly radiculopathy, which is currently thought to be due to nerve root damage) (CLP) and CCP and assist him in identifying the point where medical treatment should cease. At this point, treatment and rehabilitation efforts can stop and the physician, patient, and employer can feel comfortable with a recommendation to return to full-time work, limited work, settle claims, retirement, etc. Medical costs should be reduced while the efficacy of medical treatment improves. PA1 4. Identify those patients who are suffering disability from the pain of CLP or CCP from those who are not suffering from the pain of neck pain, backache and/or radiating pain. (Radiating pain is defined as pain that is perceived in one or both buttocks and/or one or both lower extremities. Radiating pain is currently divided into two categories: (1) referred pain which means pain that radiates into the buttock(s) and thighs and remains above the knee; and (2) radiculopathy which means pain which radiates into the buttock(s), thigh and below the knee, sometimes to the foot. Referred pain may be due to muscles, fascia, etc., while radiculopathy is thought to be due to nerve root damage.) This will assist the proper authorities in placing those who qualify for financial assistance because of an objectively documented back pain condition in the appropriate social program, and to identify and remove those who do not medically qualify. PA1 5. Aid the courts and others concerned with assessing correctly the compensable damages of pain and suffering secondary to neck pain, backache and/or radiating pain.
An objective test for peripheral nerve damage, in general, would allow the clinician to verify whether patients with peripheral nerve problems with neurological symptoms (for example: carpal-tunnel syndrome; brachial plexus problems; thoracic outlet syndrome; peripheral nerve injuries; peripheral nerve damage as a result of disease, ageing, congenital abnormalities, neoplasms; optic or auditory nerve damage due to many conditions, etc.) suffer from nerve damage, which would dictate a particular course of therapy.
Clinical tests for CCP or CLP include inspection, palpitation and manipulation. The vast majority of clinical tests depends upon the patient reporting a painful or other type of response, and are therefore unreliably subjective. Objective clinical tests in the current state of the art include reflex changes, spasm and properly performed straight leg raising tests, and may or may not aid in the diagnosis of lower back syndrome. Moreover, they neither quantitate nor monitor the progression of lower back syndrome.
Thermograms, psychological interviews (e.g., McGill and MMPI tests), polygraphs and instrumentation tests may also be used to assist in the diagnosis of CLP and CCP. However, none of these is completely accurate because they are also subjective and depend on the patient reporting the type and degree of response sustained.
Laboratory tests such as X-rays, CT scans, MRI's, myelograms, discograms, EMG's and bone scans can only delineate the presence or absence of possible pain-producing lesions which must then be correlated with the clinical findings of CLP or CCP. They do not detect the presence or absence of CLP or CCP per se, nor in any way quantitate them. Further, it is not uncommon to have false positive and false negative results with these tests (reported rates of error of about 20-50%). All or any of these tests may be negative and the patient may continue to complain; on the contrary, all or any of these tests may be positive and a patient may remain asymptomatic. Moreover, not only are these tests expensive, some of these tests expose the patient to unnecessary radiation.
The capacity to obtain diagnostic information from proteins, particularly blood proteins, has progressed rapidly since the middle of the 19th century when it was believed that serum contained but a single protein, albumin. By 1887, Lewith had demonstrated, by salt precipitation, that serum proteins could be separated into the albumins and globulins. The ratio of albumin to globulin (A/G ratio) was shown to have diagnostic value and is still in use today. With the introduction of electrophoretic separations, immuno-analytic techniques and enzymatic assays, the number of plasma proteins of diagnostic value has grown exponentially. The examination of specific blood proteins has proven to be an invaluable diagnostic aid, as in the monitoring of creatine phosphatase levels in determining cardiac damage following a myocardial infarct. The increased resolution and detection of plasma proteins with two-dimensional electrophoresis [O'Farrell, J. Biol. Chem., Vol. 250, pp. 4007-4021 (1975)] combined with silver-staining [Merril, Proc. Natl. Acad. Sci., USA, Vol. 76, pp. 4335-4339(1979)] allows investigators an examination of over one thousand proteins in human plasma and approximately 300 proteins in human cerebrospinal fluid.
Anderson et al. [Proc. Natl. Acad. Sci., USA, Vol. 74, pp. 5421-5425 (1977)] initiated the mapping and the identification of the plasma proteins resolved by two-dimensional electrophoresis. The goal of this work was to use these proteins for screening genetic variants. By 1984, they were able to identify only 38 of 646 serum proteins visualized by their electrophoretic and staining systems [Anderson et al., Plasma Proteins, Vol. IV, pp. 221-269, Academic Press, New York (1984)].
It has been suggested that two-dimensional gel electrophoresis can be used to correlate the presence of a protein in serum or tissue, or an increase in its amount, with various diseases [Tracy et al., "Two-Dimensional Gel Electrophoresis: Methods and Potential Applications in the Clinical Laboratory", J. Clin. Lab. Autom.,Vol. 3, No. 4, p. 235 (1983)]. It has also been noted that development of a protein "profile" for disease states may be useful in diagnosis [Tracy et al., supra at 242].
However, the increase in resolution provided by two-dimensional electrophoretic techniques and the increased detection available with recently developed staining methods has not yet resulted in widespread clinical applications of this methodology. Thus, the diagnoses of disease states in general, and chronic back pain in particular, by way of two-dimensional gel analysis is new, there being only one such reported method. This method utilizes two-dimensional gel protein analysis of cerebrospinal fluid to distinguish Creutzfeldt-Jakob disease from other causes of dementia [Harrington et al., U.S. Pat. No. 4,892,814).
Harrington et al. [Clinical Chem., Vol. 31, pp. 722-726 (1985)] also found some proteins associated with Parkinson's disease and schizophrenia, which may or may not be of diagnostic value. Some proteins mapped and identified by two-dimensional electrophoresis of plasma [Anderson et al., 1984, supra] and cerebrospinal fluid [Goldman et al., Clin. Chem., Vol. 26, pp. 1317-1322 (1980)] have demonstrated to be polymorphic and thus may provide for genetic and forensic applications, but have not proven reliable as diagnostic markers for particular diseases.
To overcome the aforementioned deficiencies in the art the present inventors have developed an objective, quantitative test for diagnosing peripheral nerve damage, particularly that which causes spinal pain and more particularly CLP or CCP. The test utilizes two-dimensional electrophoresis to analyze the increased or decreased concentrations of certain proteins in a body fluid sample from a patient as compared to a normal control. During the course of developing this test, the present inventors discovered a protein marker, which is indicative of peripheral nerve damage.

Methods for the diagnosis of peripheral nerve damage

The United States of America as represented by the Secretary of the Department of Health and Human Services


The determination of axial and lateral displacement in a material subject to compression is determined by fitting a multi-dimensional model function to the match between corresponding portions of the material in two states of compression. In one embodiment, iso-contour lines in a correlation between a reference kernel and a target kernel are fit to an ellipse whose center defines the maximum correlation and hence the displacement.

The present invention relates to elasticity imaging including but not limited to strain imaging and in particular to an improved method of determining displacement vectors used to produce such images.
Strain imaging produces images revealing the underlying elastic parameters of the material being measured. When used in medicine, strain imaging is analogous to palpation by a physician, that is, the pressing of tissue by the physician to feel differences in elasticity in the underlying structures.
In a common form of strain imaging, two separate images are obtained with the measured material in different states of deformation, typically, as deformed by a mechanical or physiological stimulus. In ultrasound strain imaging, the ultrasound probe itself may be used to provide this deformation.
The two images are analyzed to deduce the amount of displacement in the material at a number of corresponding regions. The gradient in these displacements, determined as a function of the spatial location of the regions, provides strain information generally reflecting the elasticity of the tissue. An example of such strain imaging and a description of techniques for determining displacement of tissue between two images are described in detail in U.S. Pat. No. 6,508,768 entitled: Ultrasonic Elasticity Imaging, and in pending U.S. application Ser. No. 12/258,532 filed Oct. 27, 2008 and entitled: Ultrasonic Strain Imaging Device with Selectable Cost-Function, and in pending U.S. application Ser. No. 12/645,936 filed Dec. 23, 2009 and entitled: Elasticity Imaging Device with Improved Characterization of Seed Displacement Calculations, all assigned to the same assignee as the present invention and hereby incorporated by reference.
The displacement between corresponding regions of the material in the first and second state of deformation can be determined by identifying a multi-point region (i.e. a reference kernel) in the material in the first state of deformation and moving this kernel within a two- or three-dimensional search region over a search region of the material in the second state of deformation. The displacement vector is determined by the best match between the reference kernel and its overlapping portion in the search region of the material in the second state of deformation (i.e. the target kernel). The best match may be determined by evaluating a similarity of the data of the reference and target kernels, for example, as a sum of the magnitude of differences between individual samples of these two kernels or other similar technique.
In ultrasonic imaging systems, the determination of displacement may be limited to an axial direction defined by the propagation of the ultrasonic signal. This is because motion tracking in the lateral direction (perpendicular to the axial direction) tends to be of low quality possibly because of the loss of phase information because sequential data in the lateral direction is assembled from multiple rather than a single beam.
Nevertheless lateral displacement information can be valuable because it provides a more complete picture of elasticity necessary for many types of measurement.

Coupled axial and lateral displacement estimation for elasticity imaging


A method and a system for forwarding multicast data packets across a plurality of telecommunications subnets interconnected by routers in which a data packet is received within a subnet of the plurality of telecommunications subnets. When the data packet is a multicast data packet, a multicast IP address for the multicast data packet is determined. A multicast forwarding database is accessed for determining a LAN Emulation Client associated with the multicast IP address, and a Broadcast Unknown Server associated with the multicast IP address for the multicast data packet is determined. The multicast data packet is sent to the Broadcast Unknown Server associated with the multicast IP address for the multicast data packet through the LAN Emulation Client using a point-to-point connection. The Broadcast Unknown Server sends the multicast data packet inter-subnet to each router associated with the multicast IP address for the multicast data packet using a point-to-multipoint connection, with at least one multicast host being connected to a subnet that is different from the subnet in which the multicast data packet was received.

1. Field of the Invention
The present invention relates to the field of telecommunications. More particularly, the present invention relates to a method and a system for routing Internet Protocol (IP) multicast traffic over Asynchronous Transfer Mode (ATM) networks.
2. Description of the Related Art
Many applications used on the Internet have multiple sources, or senders, and hosts, or receivers, that participate, or interact, with each other. Previously, conventional unicast techniques were used for sending the same data packet to each host of a multicast group over a circuit that was specifically established between a source and the host. A conventional unicast approach for multicasting traffic, however, is wasteful in terms of both bandwidth and circuit resources.
To overcome the drawbacks of using unicast techniques for multicast traffic, techniques and protocols have been developed so that a multicast data packet is sent along a predetermined route of routers, or switches, and replicated at a point closest to a destination host, thereby reducing the amount of multicast traffic. For example, a number of routing protocols have been developed for creating distribution routes between a source and the hosts of a multicast group. Routers and end stations have become xe2x80x9cmulticast awarexe2x80x9d by using multicast protocols such as the Distance Vector Multicast Routing Protocol (DVMRP), the Multicast Open Shortest Path First (MOSPF) protocol and Protocol-Independent Multicast (PIM).
The DVMRP protocol is widely used in the Multicast Backbone (MBONE) and generates a separate distribution tree for each respective source and destination host group. The distribution tree, also referred to as a spanning tree, provides the shortest path from a source to each host in a multicast group. A spanning tree is constructed for a multicast group by the source initially broadcasting, or sending, a message to an adjacent router that is propagated to all other routers in the network so that the message reaches each participating host. The message effectively registers the multicast group with reach router receiving the message. If no members for a registered multicast group are connected to a particular router, the router sends a pruning message to the previously adjacent router so that the router sending the pruning message is removed from the spanning tree. As a result, the spanning tree that is eventually generated provides the shortest path between the source and every host in the network. Periodically, the broadcast and pruning operations are performed for updating the spanning tree. While the DVMRP protocol works well for a densely-distributed multicast group, the overhead processing associated with message broadcasts and maintenance of state information can become expensive for a sparse distribution of hosts across a wide area network.
The MOSPF protocol is a multicast routing protocol that is built on top of the OSPF protocol, thereby providing the ability to create multicast trees having an OSPF routing domain. Each MOSPF router receives information about hosts that are interested in a particular multicast group through an Internet Group Management Protocol (IGMP) registration process. Consequently, all routers in the OSPF domain contain information relating to the complete topology of the network and can construct the optimum path between a source and any other host in the domain. Nevertheless, multicast trees generated using the MOSPF protocol cannot span OSPF domain boundaries. Further, the MOSPF protocol generates significant amounts of overhead routing information that is continuously exchanged between routers in the network so multicast trees spanning large domains do not scale well.
The PIM protocol, developed by the Internet Engineering Task Force (IETF), addresses problems associated with crossing domain boundaries, and is independent of any underlying unicast protocol. The PIM protocol includes a dense mode and a sparse mode. Dense-mode PIM (PIM-DM) is suitable for environments in which many of the different domains, or subnets, contain at least one host participating in a multicast group and in which network bandwidth is not critical. Unlike the DVMRP protocol, the PIM-DM protocol uses a simple technique of sending a data packet arriving at a router to all adjacent downstream routers. The adjacent downstream routers, in turn, send the packet to their respectively adjacent routers. The routing tree is pruned as each router determines whether there are any hosts participating in the multicast group that are connected to the router.
When the hosts in a network are sparsely distributed, the overhead associated with PIM-DM of flooding information through a network becomes too significant and the PIM-SM protocol is used. In PIM-SM, a host that is interested in joining a particular multicast group is responsible for initiating a join operation to join the multicast routing tree associated with the multicast group. A join request is sent from the interested host towards the source of the multicast tree. The join request is propagated toward the source until the request encounters a router that already has a host participating in the desired multicast group. The routing tree is then updated to include all of the routers between the host initiating the join operation and the router where the propagation of the join request terminates.
Deployment of multicast protocols on routers has proceeded at a steady pace. Nevertheless, there are still so-called xe2x80x9cislandsxe2x80x9d of routers that are multicast-aware that are separated from other islands of multicast-aware routers. FIG. 1 is a schematic block diagram showing an exemplary conventional MBONE network 10 having a plurality of multicast-aware routers 11 and unicast routers 12. A multicast-aware router or a group of multicast-aware routers that are separated from other multicast-aware routers 11 by one or more unicast routers 12 are referred to as islands. In order to transport multicast traffic between multicast-aware routers 11 across one or more unicast routers 12, a technique known as xe2x80x9cmulticast tunnelingxe2x80x9d is used. That is, a multicast-aware router 11 encapsulates multicast traffic inside a unicast packet. The encapsulated multicast traffic is then sent, or tunneled, across a portion of the network having unicast routers.
A number of other protocols are under development by the IETF that run on top of conventional routing protocols and which provide the ability for an application to reserve resources in a network so that a specified Quality of Service (QoS) can be achieved. Examples of these particular protocols are the Resource Reservation Protocol (RSVP) and the Real Time Protocol (RTP).
The ATM Forum has developed a specification, known as the LAN Emulation specification (LANE), that permits Legacy LANs- and ATM-connected hosts to communicate across an ATM link without changes to existing applications or software. The LANE specification defines an Emulated Local Area Network (ELAN) environment in which, from the perspective of a legacy application, an ATM network looks appears to be a LAN segment. There are three special entitles in a LANE environment that are referred to as a LAN Emulation Server (LES), a Broadcast Unknown Server (BUS) and an LAN Emulation Configuration Server (LECS). The LES registers and resolves ATM addressing by labeling each end station with a Medium Access Control (MAC) layer and an ATM address. The address mapping is used by an ingress LAN Emulation Client (LEC) for setting up a cut-through path to an egress LEC. The BUS is used for distributing broadcast and multicast traffic within the LANE environment.
When a LEC sends a multicast or broadcast packet to other multicast group members within an ELAN, the packet is sent to a BUS. The BUS forwards the packet to all the other LECs within the ELAN environment on a point-to-multipoint virtual channel connection (VCC). An alternative entity to a BUS is a Special Multicast Server (SMS). A LEC wishing to receive data for a multicast address registers with an SMS and is added to the desired multicast group. Traffic received on the SMS for a particular multicast group is forwarded only on the point-to-multipoint circuit for the multicast group, thus preventing other LECs within the ELAN environment from receiving traffic in which they have no interest. While the LANE specification operates with legacy LANs- and ATM-connected hosts, the LANE specification applies only to a single ELAN environment, which, by definition, is a single subnet of an ATM network. A multicast solution in which an ELAN spans different subnet boundaries is not defined under the LANE specification.
Multiprotocol over ATM (MPOA) is a standard that is built on top of the LANE and the NHRP protocols. The MPOA protocol uses LANE when traffic is confined within a single subnet, but uses the NHRP protocol when traffic crosses subnet boundaries. FIG. 2 is a schematic block diagram showing a conventional MPOA implementation traversing a plurality of subnets 21. As data initially begins to flow from a source 22 to a destination host 23, the data follows a default data path 24 through each subnet 21 using ELAN techniques. At each boundary router 25, the packet is reassembled and Level 3 processing occurs so that the packet can be successfully forwarded to the next subnet 21. While the data packet is traversing default data path 24, a NHRP request is generated for determining the ATM address of destination host 23. Once the ATM destination address information is available, source 22 can set up a direct unicast connection 26 to destination host 23 using NHRP protocol concepts, thereby bypassing all router hops and expensive Level 3 processing.
For each of the conventional IP multicast routing protocols, such as DVMRP, MOSPF, PIM, LANE and MPOA, a considerable amount of state information must be exchanged between routers participating in a multicast. Consequently, overhead traffic, including xe2x80x9cjoinxe2x80x9d and xe2x80x9cprunexe2x80x9d messages, becomes a significant portion of the multicast traffic as a multicast group grows in size. Further, for the DVMRP, MOSPF and PIM protocols, a multicast data packet flows hop-by-hop from one multicast router to the next until the packet reaches its destination. At each hop, Level 3 processing occurs, thereby causing considerable segmentation and reassembly overhead processing. When the LANE and MPOA protocols are used, multicast traffic is confined to an ELAN. Consequently, a host desiring to join a multicast group, but not belonging to a particular ELAN is unable to participate in the multicast session without first becoming a member of the ELAN. This poses a significant problem for dynamically altering membership to a multicast group because a LAN Emulation client (host) can belong to only one ELAN at a time.
What is needed is a way to forward multicast traffic across an ATM network that does not incur significant overhead processing expenses, that scales well, that reduces the number of router hops experienced by a multicast packet when forwarded across the ATM network, and makes efficient use of network resources and network bandwidth.
The present invention provides multicast traffic forwarding across an ATM network that does not incur significant overhead processing expenses, scales well, reduces the number of router hops experienced by a multicast packet when forwarded across an ATM network, and makes efficient use of network resources and network bandwidth. The advantages of the present invention are provided by a method and a system for forwarding multicast data packets across a plurality of telecommunications subnets interconnected by routers in which a data packet is received within a subnet of the plurality of telecommunications subnets. When the data packet is a multicast data packet, a multicast IP address for the multicast data packet is determined. A multicast forwarding database is accessed for determining a LAN Emulation Client associated with the multicast IP address, and a Broadcast Unknown Server associated with the multicast IP address for the multicast data packet is determined. The multicast data packet is sent to the Broadcast Unknown Server associated with the multicast IP address for the multicast data packet through the LAN Emulation Client using a point-to-point connection. The Broadcast Unknown Server sends the multicast data packet inter-subnet to each router associated with the multicast IP address for the multicast data packet using a point-to-multipoint connection, with at least one multicast host being connected to a subnet that is different from the subnet in which the multicast data packet was received. When the data packet is not a multicast data packet, the data packet is sent to a destination address for the data packet using intra-subnet techniques.

IP multicast over routed ATM network using lane