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Ss7 signaling example – Dialogic SS7G2X User Manual

Page 137

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137

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

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.

Signaling


Gateway

PC 1

SEP 2
PC4

STP2

PC3

STP1

PC2

SEP 1

PC5