Where can I find more information on SIGTRAN?

Description: OpenSS7 Frequently Asked Questions #14.

SIGTRAN is a working group of the Internet Engineering Task Force (IETF). It provides protocols for the transport of signalling information over IP. Also see our SIGTRAN page. In particular, the OpenSS7 stack supports the following SIGTRAN protocols: (Also see our SIGTRAN page here.)

ISUA

This is an SS7 ISUP protocol at the ISUP circuit for an ASP providing ISUP application at a distance from a signalling gateway (SG) over SCTP/IP. The specification for ISUA is embodied in the Internet-Draft draft-bidulock-sigtran-isua-03.txt. The OpenSS7 stack uses ISUA to provide redundancy at the CC boundary. OpenSS7 ISUA is a STREAMS implementation running over OpenSS7 SCTP and providing the same interface as an OpenSS7 ISUP driver. It is an integral part of the OpenSS7 stack.

TUA

This is an SS7 TCAP (TC-Sublayer) protocol at the TC SAP (TC to TC-User) for an ASP providing TCAP application at a distance from a signalling gateway (SG) over SCTP/IP. The specification for TUA is embodied in the Internet-Draft draft-bidulock-sigtran-tua-04.txt. The OpenSS7 stack uses TUA to provide redundancy at the TC boundary. OpenSS7 TUA is a STREAMS implementation running over OpenSS7 SCTP and providing the same interface as an OpenSS7 TC driver. It is an integral part of the OpenSS7 stack.

SUA

This is an SS7 SCCP Level 4 protocol at the L4 (SCCP) SAP (SSCP to SCCP-User) for an ASP providing SCCP-Subsystem applications at a distance from a signalling gateway (SG) over SCTP/IP. The specification for SUA is embodied in the Request for Commonts rfc3868.txt. The OpenSS7 stack uses SUA to provide redundancy at the SCCP boundary. OpenSS7 SUA is a STREAMS implementation running over OpenSS7 SCTP and providing the same interface as an OpenSS7 L4 driver. It is an integral part of the OpenSS7 stack.

M3UA

This is an SS7 MTP Level 3 protocol at the L3 SAP (MTP to MTP-User) for an ASP providing MTP-User applications at a distance from a signalling gateway (SG) over SCTP/IP. The specification for M3UA is embodied in the Request for Comments rfc3332.txt. The OpenSS7 stack uses M3UA to provide redundancy at the MTP3 boundary. OpenSS7 M3UA is a STREAMS implementation running over OpenSS7 SCTP and providing the same interface as an OpenSS7 L3 driver. It is an integral part of the OpenSS7 stack.

M2UA

This is an SS7 MTP Level 2 protocol at the L2 SAP for and ASP controlling SS7 links at a distance from a signalling gateway (SG) over SCTP/IP. The specification for M2UA is embodied in the Request for Comments rfc3331.txt. The OpenSS7 stack uses M2UA to provide redundancy at the MTP2 boundary. OpenSS7 M2UA is a STREAMS implementation running over OpenSS7 SCTP and providing the same interface as an OpenSS7 L2 driver. It is an integral part of the OpenSS7 stack. OpenSS7 submitted a test specification for M2PA in an Internet Draft draft-bidulock-sigtran-m2ua-ss7test-02.txt. This test specification is also included with OpenSS7 stack.

M2PA

This is an SS7 MTP Level 2 Peer-to-Peer Adaptation Layer for simulating an SS7 link using SCTP/IP. The current specification for M2PA is embodied in the Request for Comments rfc4165.txt. OpenSS7 provides an implementation of M2PA over our STREAMS SCTP. The implementation passes 73 Q.781 conformance tests and is available for an integral part of the OpenSS7 stack. M2PA was written to the same interface as our SS7 MTP Level 2 hardware drivers. OpenSS7 submitted a test specification for M2PA in an Internet Draft draft-bidulock-sigtran-m2pa-test-06.txt. This test specification is also included with OpenSS7 stack.

SCTP

This is the common transport protocol which is used by many of the other adaptation layers for SS7. It is a multiple stream-based protocol similar to multiple streams of TCP and provide reliable transport of data ``chunks'' between two IP hosts. Although SCTP can run over UDP, it has been specified to run directly over IP. The specification for SCTP is RFC 2960. OpenSS7 provides several implementations of SCTP for Linux: SCTP for LiS STREAMS (kernel) and SCTP for Sockets (kernel). Both releases can be obtained from our downloads page.

TALI

TALI provides either an MTP Level 3 protocol at the L3 SAP (MTP to MTP-user) for a Level 4 protocol at the L4 (SCCP) SAP (SCCP to SCCP-User) for an ASP providing MTP-User or SCCP-Subsystem applications at a distance from a signalling gateway (SG) over TCP/IP. The specification for TALI is embodied in the Request for Comments rfc3094.txt. The OpenSS7 does not yet implement TALI.

IPlink

IPlink provides MTP Level 2 over TCP/IP rather than a physical SS7 link interface. OpenSS7 supports an SS7 link virtual device which provides IPlink capabilities. The specification for IPlink is embodied in the Internet Draft draft-bressler-sigtran-ipss7l2-00.txt. The OpenSS7 stack uses IPlink to provide SS7 L2 emulation over UDP. It is an integral part of the OpenSS7 stack.