nnection. In defining an assembly, one must define the assembly endpoints. This involves specifying the source network element, which is the network element where the connection begins, and the start and end locations of the source network element. The same must be specified for the destination network element. Finally, one must specify the type of link. Defining an internal assembly link also involves defining a source and destination network element, their start and end locations and the type of link. Transmission or transport circuits are a central component of network inventory. Thus, an inventory management product should provide the ability to query circuits that are in the inventory. Circuits are queried on the basis of key features. Some are listed in Table 10.2. When querying, a user may want to specify filters with one's query to speed the process of finding the records for the relevant circuits for which one is searching. Possible filter options are given in Table 10.3. The results of a query will display a variety of information depending on the particular OSS inventory solution. Typically, something like the information in Table 12.4 might be displayed. Circuit capacity details (see Tables 10.5 and 10.6) are just as important as the presence of circuits themselves, the services they provide and the customers to Table 10.2 Circuit attributes. Query type Description Service ID Searches for service IDs Circuit name Directly search circuit names Customer Searches for circuits and returns customer circuits Services affected A circuit name is specified and the query returns child circuits associated with the circuit specified provided that those circuits are leased All service affected A circuit name is specified, and the query returns a list of carriers and the child circuits of the specified circuit that are leased by each carrier All bearers A hierarchical list is given of circuits associated with the specified circuit Network element A list of circuits that use the specified type of network element is 