Trap Receiver mechanism allows more than one application simultaneously to listen for traps at a port and allows any application to register for multiple ports. Registration is carried out through API methods. 12.6 TL1 Autonomous Messages Using a fault management OSS such as FMS, the user can establish a connection to TL1-enabled devices and listen to autonomous messages sent by those devices. A TL1 fault management module will receive an autonomous message, parse construct the TL1 event object and pass it through the event parsers and filters. The event parsers and filters can be customised to modify/convert the event before it is stored in the database. A TL1 connection process is an FMS process that handles TL1-related functions such as establishing connections to the TL1 devices and listening for autonomous messages. A configuration file lists the TL1 devices to be managed. This file can be used to specify the list of TL1 devices, the various login commands and the initial- ization commands for the devices. IP address, TL1 port and connection handler entries must be given for each device. The TL1 port is the port in which the TL1 agent is running. The TL1 port must be specified since the TL1 agent is not running on any specific port. Multiple ports can also be specified using comma-separated values. The name of each device group configured is specified by the device group name. This name is used to allow TL1 devices to be added at runtime. Once all necessary 12 Fault Management parameters have been configured at the device group level and a device group name has been specified, the user can use the runtime Add Node facility from the Fault Client, a client application of FMS, to discover and add any TL1 device not already listed in the configuration file. All parameters specified for a device group are used to discover, connect and add the TL1 managed objects to the topology database. The dictionary is the XML file with the syntax for input and output messages for any particular type of TL1 device. FMS is equi