ATIS and the SIP Forum have formed a Joint Task Force that is focused on building a specification that will enable North American service providers to establish IP communications network-to-network interface (NNI) arrangements.
The two organizations said that the task force will support wide-scale availability of IP-based voice services and lay the groundwork for ubiquitous advanced real-time communications such as high-definition voice, point-to-point video calling, and multimedia text across wireless, wireline and cable providers.
While service providers are transitioning to IP, the reality today is that interconnection between two service providers still occurs via the PSTN's TDM facilities.
Similar to the way service providers establish External Network to Network Interconnection (E-NNI) agreements to extend their Ethernet networks to serve out of territory opportunities, IP-based SIP interconnection between service providers has to be negotiated and engineered on a case-by-case basis. Also, there is no agreed upon methodology on how to translate phone numbers for routing SIP to IP interconnection.
That's not to say that service providers aren't making interconnection efforts.
Verizon, for one, has established VoIP interconnection agreements with both Vonage (NYSE: VG) and Comcast (Nasdaq: CMCSA). However, some competitive carriers like CBeyond (Nasdaq: CBEY) and others accused the ILEC of not agreeing to negotiate terms, claims that Verizon has refuted.
Meanwhile, fellow RBOC AT&T (NYSE: T) has set 2020 as the date when it will migrate its TDM network to IP. Earlier this month, the telco brought proposals to the FCC to begin testing its TDM-to-IP transition and to set a timeline to make these changes throughout its 4,700 wire centers.
- see the release
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