SSN
Sub‐system Number. Identifies the sub‐system within an SS7 network element.
Definition:
Mobile Switching Center Selective Router. Table on the FMCC that allows different trunk types (between the MSC and
the Selective Router) to be specified on a per‐PSAP basis. There is one path from an MSC to a PSAP, and that path is
through a Selective Router (SR). The type of trunk between the MSC and the SR must be known in order to properly
format the ORREQ return result. Using this table, different trunk types can be defined for an MSC.