Dialogic SS7G2X manual SS7 MTP2 Operation, SS7 M2PA Operation

Dialogic® SS7G2x Signaling Server SGW Mode User Manual Issue 4

An SS7 Route (C7RT) identifies the link sets that are used to reach an eventual Destination Point Code

(DPC). Two SS7 routes cannot have the same DPC within the same network. An SS7 route utilizes link sets (LS1 and LS2) to adjacent points to reach an eventual destination. An adjacent point can be a Signaling Transfer Point (STP), where SS7 information is forwarded on into the SS7 network, or the eventual destination. SS7 routes are managed using the C7RTx commands.

SS7 MTP2 Operation

An SS7 signaling link (C7LINK) processor (EQU) receives and transmits SS7 signaling information over a timeslot (TS) on an E1 or T1 bearer or a serial V.11 interface. An SS7 Signaling link is identified uniquely within an SS7 link set by the Signaling Link Code (SLC). Signaling links are managed using the C7SLx commands.

Figure 6. SS7 Signaling Example

Signaling

Gateway

PC 1

STP1

PC2

STP2

PC3

SEP 1

PC5

SEP 2

PC4

Figure 6 demonstrates a Signaling Gateway routing to two SS7 Signaling End Points (SEP). The first SEP is reached by a pair of STPs, while the second SEP is reached directly from the Signaling Gateway. Example MML for the above configuration is:

C7LSI:LS=1,OPC=1,DPC=2,SS7MD=ITU14,LSSIZE=2,NI=2,NC=1;

C7LSI:LS=2,OPC=1,DPC=3,SS7MD=ITU14,LSSIZE=2,NI=2,NC=1;

C7LSI:LS=3,OPC=1,DPC=4,SS7MD=ITU14,LSSIZE=2,NI=2,NC=1;

C7SLI:C7LINK=1,LS=1,EQU=2-1,TS=1-3-16,SLC=0;

C7SLI:C7LINK=2,LS=1,EQU=3-1,TS=2-3-16,SLC=1;

C7SLI:C7LINK=3,LS=2,EQU=2-2,TS=1-4-16,SLC=0;

C7SLI:C7LINK=4,LS=2,EQU=3-2,TS=2-4-16,SLC=1;

C7SLI:C7LINK=5,LS=3,EQU=2-3,TS=3-3-16,SLC=0;

C7SLI:C7LINK=6,LS=3,EQU=3-3,TS=3-4-16,SLC=1;

C7RTI:C7RT=1,NC=1,DPC=2,LS1=1,LABEL=STP1;

C7RTI:C7RT=2,NC=1,DPC=3,LS1=2,LABEL=STP2;

C7RTI:C7RT=3,NC=1,DPC=4,LS1=3,LABEL=SEP2;

C7RTI:C7RT=4,NC=1,DPC=5,LS1=1,LS2=2,LABEL=SEP1;

SS7 M2PA Operation

The Signaling Gateway is capable of replacing TDM SS7 links with signaling links operating over IP providing the equivalent functionality to MTP layer 2 by using the SIGTRAN M2PA protocol. Typically M2PA signaling links would be used when the Signalling Gateway is either offering longhaul over IP operation between two SEPs, or when two Signaling Gateways are acting as a single Point Code and the inter Signaling Gateway SS7 link is provided by M2PA over IP.

For M2PA operation, rather than associating an EQU or TS with an SS7 signaling link (C7LINK), the SS7 link is instead associated with a SIGTRAN link (SNLINK) defined to be of type M2PA. The SIGTRAN link is used to identify a SCTP Association as being used for M2PA operation.

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