Software for Signaling Interworking

Software for signaling interworking, which includes Embedded SIP source code software, an ISDN protocol stack, an QSIG protocol stack and an T1 RBS  E1 R2 CAS protocol stack will accelerate development and interoperability testing of your gateway or similar product.

SIP-PSTN Signaling Interworking Features

  • SIP User Agent software SIP Stack
  • World-wide PRI, QSIG, BRI software Signaling Stacks
  • CAS R2 support for many countries
  • Robbed Bit Signaling stack
  • Analog Telephone ("Black Phone" or "POTS Phone") interface
  • IETF & ITU Standards-based software
  • Processor and RTOS independent software
  • Written in ANSI C source code for ease of portation
  • Developed for embedded applications

SIP-PSTN Signaling Interworking applications

SIP-QSIG Gateway

A good SIP-QSIG gateway will be compliant with RFC 4497 -- Interworking between the Session Initiation Protocol (SIP) and QSIG

Some uses of the QSIG-SIP Gateway SDK:

  • Legacy PBX-VoIP service interworking device
  • Legacy PBX-SIP based adjunct device adapter such as a PBX or Key Telephone System to
    • Voicemail
    • Interactive Voice Response system
      • Corporate Information (e.g. stock price, directions to facility)
      • Product information  (e.g. nearest store, railroad schedule)
      • User Commands (e.g. online auction)
    • Auto-Attendant
    • Auto-Dialer and announcement (e.g. school announcements, tornado warnings)
  • SIP PBX - Legacy PBX or Key Telephone System interworking device
  • Add SIP phone to legacy PBX
  • Add legacy adjunct device to SIP PBX

SIP-ISDN Gateway

A SIP to ISDN gateway is similar to a SIP to QSIG gateway, bur rather than connecting to a Private ISDN network, this gateway allows connection to the Public Switched Telephone System, and has more features than Channel Associated Signaling (CAS).  However, it does not have as many features defined as QSIG does.

The SIP to ISDN Gateway software may be ased on RFC 4497, which defines Interworking between the Session Initiation Protocol (SIP) and QSIG, modified for ISDN.

Some uses of the ISDN-SIP Gateway SDK::

  • All of the uses as the SIP-QSIG gateway, plus
  • Interworking device to enable Primary Rate ISDN or Basic Rate ISDN on SIP PBX
  • Device to enable SIP Key Telephone Systems to use PRI or BRI
  • Allow legacy PBXes, Key Telephone Systems and even Telephones to connect to a VoIP service.
    • Add remote office telephones and telephone systems to corporate PBX - centralized system may be more efficient:
    • Reduce cost of telecommunications (toll bypass)
    • Better service by operator because all operators can service all calls, not just the ones for their location.
    • Better use of adjunct devices because one larger system is shared by all branches
    • IT or Telecom department can configure, backup, and service on-site devices more easily

SIP-CAS R2 RBS Gateway software library

The uses of the CAS R2 RBS - SIP Gateway SDK are similar to the uses of the SIP-ISDN Gateway library above.  However, MF-R2 and Robbed Bit Signaling do not have all the features that ISDN and QSIG have.  R2 features vary by country, but in general, R2 has more available features than RBS.

SIP-POTS Gateway

Some uses of a  POTS-SIP Gateway are:

  • Adding VoIP capability to SOHO routers
  • VoIP Terminal Adapters (TAs)
  • POTS-VoIP multi-phone TA that allows remoting a larger number of phones to connect to a SIP PBX over an ethernet connection
    • similar to a Media Gateway, but uses SIP instead of MGCP or Megaco
  • Adding VoIP capability to existing PBXes and Key Telephone Systems