Telecom Tigers: Common Terms in Signaling Network

Tuesday, September 29, 2009

Common Terms in Signaling Network

Signaling Point (SP) - The switching or processing node in a signaling network, where the function of SS7 are implemented. like MSC in GSM or Transmit Exchange in PSTN. Every SP is identified by a number determined by Network Identifier (NI) & Signaling Point Code (SPC).
Network Identifier (NI) - It provides discrimination between International & National messages or between 2 national signaling switches. SPC uniquely idetifies a SP within the signaling network.
Originating Point (OP) - The SP at which the signaling message is generated. It is identified by Originating Point Code (OPC).
Destination Point (DP) - The SP to which the signaling message is destined. It is identified by Destination Point Code (DPC).
Signaling Transfer Point (STP) - This is a SP, that is able to route signaling messages. In GSM, every SP is STP as soon as it routes the signaling messages that must be delivered to different destination point, in this case, only MTP is used, upper layers are not involved.
Signaling Link (SL) - The packet data link that connects 2 SPs is a signaling link. It is not neccessary to have a SL in each PCM line, accoding to maximum load, there may be more than one SL between 2 SPs depending on network structure.
Link Set (LS) - A number of parallel SL connecting the same SP is Signaling LinkSet.
Signaling Route (SR) - The predetermined path a message takes through the signaling network between OP & DP is called SR. A linkset may carry several SR and hence convey traffic to several destination.
Signaling Route Set (SRS) - The signaling network groups all SR that may be used for message transferring between OP & DP is SRS.
Circuit Intetity Code (CIC) - The message requires for call setup carries an identity. The identity carries a label with source & destination of the message & also the identity of speech trunk the message is refering to, this identity is termed as CIC.