The past decade's shift to VoIP has also cemented the adoption of SIP as the session management protocol in the enterprise. This presents large organizations with an opportunity to use new and exciting applications while decreasing costs and alleviating management headaches.
Typically, new technology (such as VoIP) also introduces a whole new lexicon that defines how we think about that technology in operation. A current "new term" associated with SIP is session management, and industry chatter debates why this concept is going to be critical for enterprises as they move to a full, SIP-based, unified communications architecture. As I talk to my peers in the industry, I get the sense that, while most have heard of session management and understand that it's important at some level, they are still confused as to what exactly SIP session management is now or can be going forward.
So I am going to attempt to give some definition to this term. To level set, I'll use the commonly accepted definition that a SIP session is the SIP signaling intended to provide a media path between two parties. The media allowed by this signaling can be generated by any of a variety of applications used by enterprises today (e.g. voice, video, chat). To this point, it's important to remember that SIP is an adaptable signaling and media protocol that can be used to initiate sessions in many situations (there are currently more than 150 SIP RFPs) and therefore has been adopted by many communications vendors as their protocol of choice.
The good news is SIP's ubiquity. The bad news: it's unlikely that any single vendor will ever be in a position to offer the entire suite of SIP-enabled applications that enterprises will demand. Additionally, no single vendor will ever achieve permanent best-of-breed status and capture all market share in any individual SIP-based application area. This means there will be a need for interworking both between different SIP applications and within individual SIP application areas. (The need for interworking within a single SIP applications area will arise because SIP implementations within an application area will vary depending on the specific vendor and even on the specific release version of a single vendor's product.)
This is where SIP session management comes in.
The realities mentioned above lead naturally to the need for enterprises to deploy a SIP Session manager--a single cross-enterprise solution that can interwork all SIP applications and enforce business policy. An example of a policy would be, "no video sessions between 9:00 am and 4:00 pm because my training desk needs the bandwidth," or "the VP of Marketing always gets all the bandwidth he wants for video no matter which office he is in." The key of session management, then, is the combination of business logic with the policy enforcement concepts of users, business groups, departments or other organizational entities.
To be effective, the SIP Session manager must operate at a session management layer which is both protocol- and vendor-agnostic and provides interoperability between the various devices and applications in the network. "Session Management" as a product solution set must provide a vendor-agnostic combination of policy, signaling interworking, media interworking and endpoint management.
Look for my next post where I'll address some of the key functional areas that must be present to deploy a successful SIP session management solution. In the meantime, let me know your thoughts on this topic.
Mykola Konrad, Director of Enterprise Product Management at Sonus Networks, is joining the roster of No Jitter bloggers. We'll have his complete profile page posted shortly.
