Nortel opens SIP code for interoperability

Nortel is opening up its Session Initiation Protocol (SIP) code to the public in an effort to promote interoperability with other vendors' gear, the company announced at the Supercomm trade show.

This open-client strategy is meant to address the problem that while different companies follow a standard - in this case the signaling used for many voice-over-IP applications - their implementations might not work with each other. With another company's code to work with, vendors can write or modify their own to be compatible.

The company says that Texas Instruments (chips), Uniden (cordless phones), i3 micro (residential IP gateways), and Polycom (voice/video conferencing gear) say they plan to make their products compatible with Nortel's Multimedia Communications Server, which sets up SIP sessions. TI will also write reference designs so their chip customers can make SIP devices such as phones and gateways that work with Nortel's MCS gear.

This type of interoperability is key for service providers that want to offer SIP services based on MCS and need peripheral devices to work with it.

Nortel uses a Radvision SIP stack that it has customized.

Nortel also announced it has verified interoperability between Nortel gear and Avici core routers. This is important to service providers that might want to use Nortel's edge routers in their networks because Nortel has designated Avici its partner to provide core routing. The verified interoperability includes Nortel's Multiservice Provider Edge switch routers as well as its Succession VoIP gear.

Nortel says this interoperability verification will be ongoing as the vendors update their platforms.