Recognizing IP multimedia subsystem (IMS) as an important end-point – but one that carriers need to approach pragmatically – network vendor NEC America today introduced its “light IMS” product set and migration path.

At the core of the light IMS approach is NEC’s Service Convergence Integrated Platform (SCI-P), a blade-based server platform that brings together a SIP server based on IETF (rather than 3GPP) standards; integrated service deployment platform (SDP) and OSS/BSS capabilities; plus service enablers for building an array of services on to of the platform.

SCI-P is targeted at mid-tier wireline and wireless carriers, allowing them to get many of the architectural and service advantages of IMS today while via a software upgrade move to a full IMS signaling, call control and application platform down the line.

“NEC’s move is a reminder that IMS is directionally correct, but carriers need a pragmatic approach to get themselves headed in the right direction,” said Elisabeth Rainge, director of network software research for IDC. “Following IMS to the letter of the specifications is not what it’s all about. IMS offers a great framework and template but [how it’s deployed] has to be personalized and customized by every operator.”

NEC has already developed and delivered a full IMS product – built to full 3GPP specs and focused initially on wireless carrier requirements, said Nick Satomi, vice president, NEC Carrier Solutions. “But we realized that it takes years to get to the point where we’ll see large-scale IMS implementations,” he said. “In the meantime, what we found was that some fixed network operators were also looking at IMS, with IP and VOIP as an entry point, focusing on new revenue opportunities.”

For NEC, a “light” approach to IMS is defined by a handful of things, Satomi said. The first is the deployment of IETF-defined, rather than full 3GPP-defined SIP servers. Another major difference is at the HSS, or Home Subscriber Server, level. Rather than a centralized HSS, NEC’s approach relies on more distributed subscriber databases, Satomi said. Finally, NEC’s approach places a larger emphasis on a service delivery platform, or SDP, as a vehicle for enabling carriers to rapidly create and deploy new services.

Whether to go full or light IMS “depends on the carrier, Satomi said. “Some carriers are committed to go full IMS. For others, they see IMS as a good concept but they are maybe far away from a large deployment.”

NEC’s SCI-P light IMS platform is available today; an update planned for the second quarter will deal with additional carrier grade deployment issues, Satomi said. NEC has begun its first deployment of the platform with an unnamed Latin American carrier, he said.