* Carriers' resolved and ongoing IP Multimedia Subsystem challenges
Today, we’ll wrap up our discussion on IP Multimedia Subsystem roadblocks as we test our final two hypotheses with the experts who are deploying IMS in commercial networks. When we began this mini-series, we suggested that one impediment to IMS deployments in carrier networks is the need for IMS to support interfaces into the service providers’ operational support systems (OSS) and back-office support systems (BSS). David Whittington at Alcatel-Lucent agrees with our hypothesis. He said that, as with any new infrastructure deployment, integrating the carriers’ OSS with IMS is THE issue and that since every carrier has its own unique and evolving OSS requirements and business processes, IMS-to-OSS integration will be an ongoing challenge requiring a strong partnership between the IMS vendor and the operator to resolve.
Ajay Gupta at communications software company Aricent believes the systems management issues won’t be easy to solve. He said that with IMS-supported fixed mobile convergence (FMC) in particular, supporting the wide variety of devices at home on a large scale with the required interoperability may prove to be difficult. Customers expect a one-stop call if the service doesn’t work and they also expect their devices to be managed. Therefore, when carriers construct a business case for FMC, they will need to make sure that the spectrum and bandwidth efficiency gains aren’t overtaken by the associated management costs.
So it seems the experts agree with our second hypothesis: OSS and BSS integration remains an unsolved issue the industry will need to address to move IMS forward – and it won’t be an easy issue to solve.
Finally, we suggested in our third hypothesis that wireless and wireline carriers that don’t sell both wireless and wireline services may have a vested interest on slow-rolling IMS-based FMC solutions while carriers that do operate both network types may hesitate to give up revenue or to change their existing business models for voice minutes. Happily for IMS proponents, the carriers proved us wrong – any tension that may have existed between wireless and wireline strategies seems to have melted away and carriers are moving to tackle the implementation in both worlds.
At AT&T, Siroos Afshar, said his company decided to combine its entire transport network into a single, global IP/MPLS network [that would support] every existing and future service. To capitalize on that decision, and since IMS supports both wireless and wireline services with session management, AT&T adopted a “Common Architecture for Real-Time Services” (CARTS), building from IMS.
Similarly, at Verizon, Bill Goodman said: “Before we called it IMS, we had spent 10 years working on integrated environments. As the industry developed an IMS framework, we’ve been happy to see it move forward as a standard.” Verizon has been working to make IMS a reality for both wireless and wireline services beginning with wireline, SIP-based VoIP for consumer, enterprise, and wholesale markets. On the wireless side, as Verizon completes its EVDO RevA upgrades, the wireless network will be able to support the quality of service needed to offer VoIP in a wireless environment that will be managed by SIP and eventually evolve to an IMS architecture.
Out thanks again to the experts for helping us test our hypotheses on IMS. We’ll keep IMS on our radar screen this year, but we’ll move on to other topics next week.
