PTCL Training & Development 1

• SIGTRAN:• SIGnaling TRANsport to carry SS7

signals over the Internet• PSTN’s signals are being carried

over IP network after converting from SS7 to IP signals

• Underlying transport vehicle is SCTP (Signaling Control transmission Protocol) to carry SS7 over IP

• PSTN signals SS7 are transmitted to SG (Signaling Gateway) which in turns converts SS7 into SIGTRAN signals

• SIGTRAN signals are sent to a SoftSwitch or to next Signaling Gateway SG

SIGTRAN Protocols….

• Basic function of SIGTRAN:• To transport PSTN (SS7) signals

over IP keeping the functions & requirements of PSTN

• Idea is to transport ISDN(Q.931, ISUP, SCCP etc) messages between IP nodes (SG, MGC, MGW) or to an IP-based database

• To provide signaling capability for Call Management and to provide media paths for IP real-time traffic

• Real-time traffic can be Voice, Music, video which needs instant transportation

SIGTRAN Protocols……

SIGTRAN Protocols Model

Adaptation Protocols

Common Signaling Transport SCTP

Standard IP protocols

Adaptation protocols-to make TCP/IP look like an upper layer protocols MTP3 (which are MTP1, MPT2, MTP3 all SS7 signals)

Redefines newTransport service

Carries SS7 signalsover IP runway

The Real IP Standard Transport means

Upper Layer protocols

Integration of SS7 & IP protocols

SS7ISUP

SCCP users,RANAP, TCAP etc

Q931SCCP

M2UA SUAM2PA M3UA IUA

MTP3

MTP2

2904 3565 2905 9900 1401

SCTP

IP

• Ease of deployment: No need to distrupt SS7, future enhancements are transparent

• Better Efficiency: Using IP over SDH and IP over fiber can achieve much higher throughput

• Flexible architecture: IP signaling is flexible than TDM-based legacy networks

• Enhanced Services: Implementation of a core IP network facilitates a variety of solutions and value added services (VAS)

SIGTRAN benefits…..

All Signaling Protocol scenario….

SGSG

H.248

PSTN

AGW

SIGTRAN

H323 /SIP

SIP-T/BICC

SS7

GSM MSC

TMG/UMG

SS7

SIGTRAN

SS SS

SIP Phone

MAPPhone BPhone A

PSTN

phones

H248

TMG/UMG

E1E1

* SIP-T: SIP for Telephone

• ISUP—ISDN User Part• SCTP– Stream Control transmission

Protocol• RANAP– Radio Network Access part• TCAP– Transaction Capability part• MTP1, 2 3 – Message Transfer Part 1, 2 ,3• M2UA, M3UA – Message 2 User

Adaptation, Adaptation 3• IUA– ISDN User Adaptation• SUA– SCCP User Adaptation• SCCP– Signaling Connection Control Point

Protocol abbreviation used….