⟩ What are the different functionalities of MTP3 layer?
Message Transfer Part level 3 (MTP3) is the network layer in
the SS7 protocol stack. It routes SS7 signalling messages to
public network nodes by means of Destination Point Codes,
and to the appropriate signalling entity within a node by
means of a Service Info Octet. MTP3 is specified as part of
the SS7 protocol and is also referred to as part of the
B-ICI interface for ATM. MTP3 sits between MTP2 and the user
parts (ISUP, TUP, SCCP and TCAP) of the SS7 protocol stack.
B-ISUP is an Application Layer protocol run over MTP3.
