SIPconnect Technical Recommendation

The SIPconnect Technical Recommendation is an industry-wide, standards-based approach to direct IP peering between SIP-enabled IP PBXs and VoIP service provider networks. This website and Forum promotes the SIPconnect initiative,  and input for future versions is supplied through this Forum.




The implementation of the SIPconnect standard benefits many participants in the delivery of voice communications.

For end users in the small business or large enterprise, SIPconnect eliminates, or greatly reduces, the need for a costly gateway at the end user's site.  In addition, new features from the service provider or the IP PBX vendor will be delivered more quickly.

For VARs and Interconnects, the SIPconnect compliant service provider will handle the complexity associated with connecting the SIP Trunk to the legacy TDM world.  This eliminates the need for a lot of integration and troubleshooting work and allows the partners to focus on other, revenue generating activities.

For Equipment and Software Vendors (Application Servers, IP PBX Vendors, SIP Proxies), SIPconnect greatly reduces the time and resources required to verify interoperability in the network.  This single item, interoperability, currently drains many man hours from the services and equipment providers that could be better used creating new and more exciting features.  This in turns reduces the amount of revenue that could be realized from those new features.

The SIP Trunking Service Provider that uses SIPconnect SIP trunks realizes higher revenue streams much more quickly.  Network services are rolled out more rapidly, greatly reducing the time to revenue for new services and features.  In addition, the service provider can greatly reduce the time and staff required to complete interoperability testing.




The SIP Forum began working on SIPconnect subsequent to the initial release of the SIPconnect Interface Specification in February, 2005 based on a proposal submitted by members of the SIPconnect initiative. The SIP Forum created the "IP PBX and Service Provider Interoperability Task Group" on July 15, 2005 to continue this work. 

In September, 2007, the SIP Forum launched the SIPconnect Compliance Program.

View the SIPconnect Compliant Announcement HERE.

The SIP Forum reached an important milestone in January, 2008 when it formally ratified version 1.0 of the SIPconnect Technical Recommendation with the unanimous approval of the SIP Forum Board of Directors and announced the formation of the SIPconnect v.1.1 Task Group.

The SIP Forum reached another milestone on March 1, 2011, when it formally ratified version 1.1 of the SIPconnect Technical Recommendation, again with the unanimous approval of the SIP Forum Board of Directors.

View the SIPconnect 1.1 Announcement HERE.

The formal adoption by the SIP Forum Board of the SIPconnect 1.1 Technical Recommendation is based on recognition that the recommendation has been through credible peer review, including broad membership and significant community review, that it is stable and is well-understood, and that it is believed to have resolved known design choices.

Notable changes and improvements from SIPconnect v 1.0 to Version 1.1 include:

  • Standards-based support for both Static (DNS-based) and Registration (SIP REGISTER-based) modes of operation
  • Description of SIP Endpoint functionality required for interworking, with detailed discussion of various error conditions and appropriate responses to those errors
  • Description of Media Endpoint functionality required for interworking
  • Focus on E.164-based SIP AoRs - the common case for deployments
  • Additional voice services (Call Forward, Call Transfer, etc.) using SIP techniques with the widest deployment, with simplified call flows
  • A detailed description of TLS usage
  • A roadmap on what implementers can expect in subsequent SIPconnect revisions (IPv6, Emergency Services, etc.)
  • Use of RFC 6140 to achieve bulk Registration of E.164-based AoRs in registration mode

To download the ratified SIPconnect Technical Recommendation Version 1.1, please click HERE.



Industry Voices on SIPconnect 1.1

"SIP trunking continues to grow in importance and today marks another step closer to SIP becoming ubiquitous in communications. As a founding member of the SIP Forum and a contributor to the SIPconnect 1.1 specification, Avaya is able to lead by example by embracing the new standards and adopting them into our Avaya Aura portfolio, thus creating an environment for SIP interoperability with Service Provider networks.“
-- Alan Johnston, Consulting Member of Technical Staff at Avaya and member of the Board of Directors of the SIP Forum.

“As early contributors to this effort, CableLabs and its members are very pleased that the technical recommendation has been unanimously approved. SIPconnect 1.1 will accelerate our ability to provide innovative, standards-based services to our business customers.”
-- Glenn Russell, Vice President, Business Services at CableLabs

“As a market leader in carrier IP Voice, GENBAND is pleased to contribute to the SIPconnect 1.1 specification and demonstrate our commitment to SIP business simplification for carriers. We are currently serving multiple carriers worldwide with SIP Business Trunking solutions and have already begun the implementation of this new SIPconnect 1.1 release. We congratulate the SIP Forum on this major achievement.”
-- Mehmet Balos, Chief Marketing Officer of GENBAND.

"Huawei Technologies has been pleased to support the SIP Forum in developing the SIPconnect 1.1 recommendation and believes this recommendation will dramatically improve our customers' ability to ensure interoperability with their own customers' SIP PBXes, and will reduce the time and resources required to deploy and support SIP-based services for small and medium-sized enterprises."
-- Rouzbeh Farhoumand, Senior Director, Core Network Standards, at Huawei Technologies USA.

"Overall, SIPconnect 1.1 is a brave attempt to define a standard for SIP Trunking and, in my opinion, all of the major areas that would enable the implementation of a SIP Trunk service have been covered. With the ratification of v1.1, it can no longer be said that there is no standard for SIP Trunking."
-- Russell Bennett, Principal at UC Insights

"SIPConnect 1.1 will help bring business telephony into the VOIP age, and leave the hundred-year-old network behind."
-- Jack Burton, Director Systems Engineering at Cablevision



SIPconnect 2.0 Work in Progress

Work has begun on SIPconnect 2.0!

The new SIPconnect 2.0 task group will produce a SIP Forum SIPconnect 2.0 recommendation that defines a common set of implementation rules for implementers who desire to interface an IP PBX with a SIP-enabled service provider. The recommendation(s) will specify which standards must be supported, provide precise guidance in the areas where the standards leave multiple options, supplement functionality gaps in existing protocols, and identify a baseline set of features that should be common to an IP PBX to service provider interface.

SIPconnect 2.0 will support a variety of new applications and technologies, including IPV6 and IPV4/6 Dual Stack components within the reference architecture, secure media (SRTP), video-enabled devices, and emergency calling (NG911/NG112) and the transport of location information.

For more information about the new and updated SIPconnect 2.0 charter, please visit HERE.



SIPconnect Certification Testing Program

The SIPconnect Certification Testing Program is a unique certification testing program that includes a new certification test suite and test platform, as well as an associated “SIPconnect Certified” logo program that will serve as the official “seal of certification” for companies products and services that have successfully passed the certification test and officially achieved conformance with the SIPconnect 1.1 specification.

The SIPconnect Certified logo will serve as the “seal of certification” for companies that have agreed to abide by the terms of an associated licensing agreement, and is permitted only on SIPconnect compliant equipment and services that has been rigorously tested and approved as compliant by the SIP Forum’s SIPconnect Certification Testing Committee. Purchasers relying on the certification mark will enjoy increased interoperability levels.

An associated SIPconnect Certification Founding Sponsor program will also be made available to industry participants, which will help fund the development and ongoing operation of the SIPconnect Certification Testing Program. The benefits of this sponsor program include an exclusive lowest-discounted price for testing, an extended three-year term including continuous recognition of support, priority scheduling of tests, and exclusive promotional activities.



For More Information

Learn more about SIP trunking and the SIPconnect specification by looking at: