With the ratification of SIPConnect 2.0, the Department of Defense (DoD) is seriously considering adopting commercial SIP for Voice & Video over IP trunking for unclassified networks. The current Unified Capabilities Requirements (UCR) technical specification requires vendors to adopt a DoD unique version of SIP known as Assured Service SIP, or AS-SIP, which was developed in 2010 to establish a common interpretation of SIP, which enforcing TLS and SRTP encryption and sustaining the military-unique Multi-Level Precedence and Preemption (MLPP) requirement.
With the maturity of SIP over the past seven years, led by the work of the SIP Forum, the industry has begun adopting SIPConnect 2.0 as the default version of SIP as it pertains to trunking. This key piece of standards work puts the transition of legacy PRI circuits to SIP trunking over Ethernet on a fast track allowing the Telecommunications Carriers to move forward with their plans to eliminate PRI offerings from their portfolios by 2020. Clearly this is good news for established IP-PBX vendors whom have adopted SIPConnect 2.0 as their SIP profile of choice for trunking, as the leading Class 5 Softswitch employed by the major telecommunications carriers here in the USA (Broadsoft) has not only adopted SIPConnect 2.0, but has been recently completed an independent verification and certification sponsored by the SIP Forum and conducted by the SIPConnect test lab ran by the University of New Hampshire.
When one reflects on the origins of why AS-SIP was established, the key points were to provide a common interpretation of SIP, that included TLS & SRTP encryption to support multi-vendor interoperability; but also to the carrier over the legacy Defense Switch Network (DSN) MLPP into the VoIP environment. With SIPConnect 2.0 now providing a path for multi-vendor interoperability that includes TLS & SRTP encryption, the only remaining requirement that would justify maintaining AS-SIP in the DoD is the need for MLPP.
To answer that question, one only needs to look at where the origination of MLPP came from. During the height of the cold war, the DoD voice environment was supported by a private telephone network (e.g. DSN) that was shared by both Command and Control (C2) users and none C2 users. The technology was required to allow C2 users to have priority access of the DSN in the event of a national security event. With the cooperation of industry, MLPP was enabled on commercial telephone switch systems and deployed across the DoD voice network. With the evolution of networks to IP, the DoD established two IP router based networks to support the DoD mission. One is unclassified and the other encrypted. Today the encrypted network hosts an existing VoIP capability that is used by near 90% of the C2 community within the DoD, which leaves one begging the question, why does the DoD need to sustain MLPP on the unclassified network for 10% of the C2 community? Why not transition them to the encrypted network to join the remaining 90% if the C2 community, freeing the unclassified network to move forward with commercially mature SIP? These are the two fundamental questions being considered by the DoD CIO office.