In just three years session border controllers have gone from a new concept, to a hot new product to just another piece of infrastructure required to operate a VoIP network. Now that this solution has reached the threshold of acceptability and the technology is more widely understood, the marketplace for companies whose sole product is based around a session controller is experiencing increased competition. This competition is coming from a number of places including competition from softswitch vendors incorporating session controllers and functionality into their product line, from router vendors incorporating session controllers into their product line, to a lesser extent from companies that give away their technology, and from foreign competition. This competition is driving the price per port downward, which in turn puts pressure on the session controller companies to widen their portfolio and redefine their product or to become acquired by another company who is looking to complete their VoIP portfolio. Due to this increased competition, the long term outlook for companies whose sole product is a session controller is uncertain. Fortunately, the outlook for VoIP networks is bright. And there are many ways to compete.

The Need For Session Control Remains

It is clear that there will not be a single VoIP architecture that serves all purposes in the evolving network. There will continue to be a market for companies deploying “traditional” softswitches that use H.248, MGCP, and SIGTRAN, those that are deploying H.323 solutions and those that are concentrating on the “next-gen” solutions using SIP.

These solution architectures are used to provide services into multiple physical networks including the wireline and wireless data network, the wireline and wireless telephone network, the cable TV market, and the power network. There is a real need to communicate not only within a specific physical topology among the various vendors and providers within that topology but also to bridge these physical networks and provide services across them in a unified way. The good news for the session controller market is that there is a common need across these solution architectures and across physical topologies for a session controller function whether it is supplied as a stand-alone device or integrated into another element such as a softswitch or router.

The Role Of Session Controller In The Network

The requirements for the session controller function vary depending on the type of network being deployed. For example in a wholesale carrier market, topology hiding, protocol conversion and network traffic management are important. In a retail VoIP solution, the SIP registrar, SIP proxy, and firewall traversal functions are essential. Different vendors take different approaches to how to address the variety of needs in the various VoIP networks, which have mirrored the PSTN. In the VoIP world, the concept of wholesale networks specializing in Class 4 services and retail networks that specialize in Class 5 services persists. Typically companies are focusing on one area or the other. Some SBCs have found a niche in wholesale carriers who are grooming (protocol conversion, topology hiding, etc.) their IP traffic as it enters or leaves their network. The SBCs take care of the vagaries involved in interconnection of two disparate networks. Other SBCs have specialized in the retail networks and find themselves solving NAT traversal issues and providing authentication services to the retail edge devices.

Addressing The Future

While these traditional session controller functions have proven themselves as an important piece of VoIP networks, there is a continuing trend for the common features to be commoditized. The features that are hot are being rolled into other product lines, and in some cases new product categories such as “NAT Traversal” solutions have sprung up at price points that are hard to compete with. To compete in this environment, some companies are rethinking and redefining what a “session controller” is. Session controllers have all the components needed to provide end-to-end services in a network.

They can control the signaling path, they control the media path, and they have the ability to monitor, report, and route using all the information available on the network. “Session controller switching” is ideally suited for VoIP networks. As this concept matures, the session controller companies are continuing to expand the role of the session controller to include new functions that overlap those of other traditional VoIP network components. For the same reasons that softswitch vendors are looking for session controller functionality, session controller companies are looking to incorporate some of the other roles that have traditionally been held by softswitches. Their role is expanding not only into the role of the softswitch to control a network, they are also branching into IVR-based media based services, endpoint services, instant messaging, and more. As this trend continues the distinction between the softswitches, session controllers and media servers continues to blur.

As the distinction between components blurs, session controller companies are having to rethink their architectures. In many cases, these session controllers were designed to be delivered as single point solutions to be inserted into these wholesale and retail networks. Many times these solutions were “closed” solutions. This has worked well for the past few years, but the commoditization of the most widely used features has driven the pricing for these features and this mechanism for packaging and delivery down. This has in turn driven companies to evolve their architectures to be more modular. Closed solutions are becoming more open. Companies that cannot adapt are going to either be acquired for their technology or go away.

Conclusion

As the market continues to evolve, there will continue to be many opportunities for companies involved in VoIP to succeed. To succeed, companies will have to continue to adapt and evolve their product lines to address the competition and still deliver the services that the market needs. Moving forward, the technology involved in deploying a network will become less important than the services that can be layered on top of it. The goal of the equipment and technology vendors, regardless of how they define themselves today, should be to deploy technology architectures that are well suited for this emerging “services oriented” network. It is clear that session controller technologies will continue to play an important role in these networks. IT

Nathan Franzmeier is chief executive officer at Emergent Networks. For more information please visit the company online at www.emergent-netsolutions.com.

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