Session Initiation Protocol (SIP) proponents insist that the protocol has the potential to truly unify communications, but there is too much variation in how vendors implement it, and SIP alone is not enough. Some vendors have suggested that a session management middleware layer will improve how enterprises establish and manage communications sessions.
Enterprises are turning to session management middleware built around SIP to establish not just voice, but collaboration and video communications among both internal and external users. To do this, IT organizations are migrating from PBXs to session management middleware for better interoperability of their communications and collaboration platforms and applications.
Enterprises are starting to think in terms of how to manage entire communications sessions -- not just phone calls. This is where session management middleware infused with SIP comes in, said ZK Research principal analyst Zeus Kerravala, who moderated a panel on the subject at Interop 2012.
"There is a middleware level that has to be brought in to act as that glue, versus waiting for this fictitious world of SIP standards and interoperability to happen," he said.
Session management: Tackling UC interoperability challenges
The industry has a long way to go before achieving full UC interoperability among all vendors and endpoints, but session management -- with SIP at its core -- has the potential to mitigate interoperability concerns the enterprise currently faces, Kerravala said.
Most enterprises have a multi-vendor UC environment, and session management middleware solutions don't have to come from one vendor either, said Gary Gordon, manager of technology and business development for NEC. NEC offers voice, IM and presence session management in a single application, and video and collaboration session management in separate applications. While the applications are tightly connected, enterprises can select middleware from third-party vendors and tie a heterogeneous environment together, Gordon said.
But multi-vendor solutions are not always user-focused, said Jack Jachner, vice president of business development for Alcatel-Lucent's OpenTouch. "The requirements are not just 'let's put a phone on the desk' anymore," he said. "Now we have to worry about what the device is, and there are more pieces to manage. We need a single point of management solution with a user focus."
While vendors are wrapping various features and functionality around SIP, some vendors rely on SIP more than others. Cisco believes that SIP trunking for interoperability within the enterprise is the low-hanging fruit of session management, said Wade Hamblin, manager of the IP Communications Business Unit for Cisco. "With SIP, we can cut the number of trunks within an organization or enterprise by 50% and, with automatic route selection within the session management [offering], users can use any trunks available."
But a focus on pure SIP could lead to connection problems for the user, Gordon noted. "[NEC] doesn't preach SIP trunking at the edge. If you lose that SIP connection from the cloud to [the enterprise], you lose your phone systems, if you have centralized trunking."
Augmentation of SIP with session management middleware is essential for now, Kerravala said. "It's still too early in SIP's lifecycle for the protocol to unify communication alone," he noted.
The real win for session management middleware is the ability to address various devices in use within the enterprise, said Jachner. "The ability to use different media and devices is changing the communication paradigm," he said. "Users need the ability to start a conversation in one mode -- like phone -- and then flip to video."
But not all users are there yet. "Maybe the low-hanging fruit is the legacy support so users can still make calls as well as communications sessions," Jachner said. "The solution needs to be hybrid."
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Session management should keep focus on user experience
The role of session management is to link together collaboration and communication applications and platforms, as well as the user or group of users. "The focus should be on user experience," said NEC's Gordon.
And session management middleware can help the enterprise replace legacy equipment without having to rip and replace. "It's really more of a plan to build toward session management," Gordon said.
"Session management is an evolution," Jachner agreed, noting that enterprises must consider what will be needed from the middleware in order to support other endpoints and media across any device -- especially mobile devices.
"The role of the vendor for session management is making sure [UC] is user-centric and not device-centric," he said, noting that sessions are often set up between users on different devices – including tablets or smartphones. "We should be setting up a session based on individuals, and session management must incorporate all of these devices."
Let us know what you think about the story; email: Gina Narcisi, News Writer.
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