Can Virtualization Succeed Where IMS Didn't?
If you've been around the telecom community as long as I have, it's almost impossible not to view the current virtualization trends -- software-defined networking and networks function virtualization -- through the cynical lens of "been there, done that."
After all, one could argue that the intelligent network and advanced intelligent network initiatives of the 1980s and 1990s had many of the same goals: creating more standard systems to end the dependence on vendor-proprietary switches and enable faster delivery of new services. And certainly the IP multimedia subsystems (IMS) directives of the last decade went down much the same path without accomplishing its ultimate goals.
In our kickoff Light Reading University class, SDN, NFV, and Policy Control: Fitting it All Together (registration required), Heavy Reading chief analyst Graham Finnie discusses the similarities between IMS and SDN/NFV from the context of policy management, a concept born of the 3GPP's IMS work.
"There are quite strong parallels between this architecture and the 3GPP IMS modular architecture from which policy control originally sprang," Finnie says. "It has the same basic three layers, although IMS didn't countenance the abstraction of routing protocols that SDN does."
The IMS architecture intended to create a northbound layer that would make it easier for network operators to build relationships between applications developers and other third-party content companies, to add value to the network services. That didn't come to pass, Finnie says, but it could still happen if virtualization succeeds as planned. "In theory, the fact that [the telecom industry] is already down that path ought to make it easier" to move to virtualization, especially in the control layer.
But IMS -- and the programs that came before it -- also offer a cautionary tale, in Finnie's book, because they show what can happen when ambitious programs run into "the sands of internal telco inertia."
This is one of many insights contained in the dynamic debut of Light Reading University, which can be viewed in our course archive. In a 35-minute presentation that opens the session, Finnie drills down on the details of virtualization in policy management, sharing these and other insights.
- As service providers have shifted from using policy for congestion management to using it to develop new services, they've faced challenges with the lack of integration of policy in IT and back-office systems. Virtualization could address aspects of this critical challenge.
- A policy controller could act as a controllers' controller, instructing SDN controllers on things like traffic flows and giving SDN controllers insight into subscriber data.
- Virtualization could also address the complexity issues that have plagued policy management architectures.
Finnie has a lot more to say that is worth hearing. If you don't have a clear understanding of the core SDN and NFV issues and trends, this is a great place to start. It's still possible to attend LRU. You can check out this and other offerings here.
— Carol Wilson, Editor-at-Large, Light Reading