What Do the Latest Announcements Tell Us About Virtualized VoLTE?

David Snow
David Snow

Summary Bullets:

  • Vodafone Italy’s virtualized VoLTE launch and China Mobile’s planned launch provide a good opportunity to assess the current state of vendors’ virtualized IMS technology
  • While there are many unanswered questions, particularly around NFV MANO, the overwhelming conclusion is that operator confidence just stepped up a gear

After the disappointment of Telkom Austria’s live virtualized VoLTE (vVoLTE) project being suspended last month (see “Even the “Downs” of NFV Projects Point “Up” in this blog), we’ve seen a couple of really significant commercial vVoLTE contracts publicized over the past few weeks – this time from the larger players. First, Huawei and Nokia Networks trumpeted their vVoLTE launch with Vodafone Italy and secondly Alcatel-Lucent, Huawei and ZTE announced their participation in China Mobile’s VoLTE launch with Alcatel-Lucent contributing its vVoLTE solution, Rapport.

So what can we read through from these announcements about the current status of virtualized VoLTE and the virtualized IMS (vIMS) infrastructure that supports it? There are quite a few, but here are three:

  • vVoLTE is Scaling Up: To start with, the indications are good that vVoLTE installations are being seen as scalable. While the announcements don’t give hard subscriber numbers, at the last count Vodafone Italy has around 26 million subscribers and Alcatel-Lucent’s nine provinces must represent a comparable number. Okay, these will not all be VoLTE-enabled immediately but it seems that both Vodafone Italy and China Mobile are confident enough in the technology to at least begin their rollouts.
  • Some VNFs are Lagging: On the other hand, there’s little to no mention of some key IMS virtual network functions (VNFs). In particular, there are no references to a virtualized home subscriber server (vHSS) and only Alcatel-Lucent’s announcement (kudos) mentions a virtualized session border controller (vSBC). For the most part, it would seem that these components remain in their physical incarnations for now. In a way that’s not surprising, as carriers have expressed concern over virtualizing and keeping track of their precious subscriber data and vendors have struggled with virtualizing the SBC media plane at scale, especially for demanding applications such as VoLTE.
  • NFV MANO is a Work in Progress: However, at the end of the day, NFV management and network orchestration (MANO) is what makes NFV work. Here, while the picture is unclear it’s also intriguing, begging quite a few questions. For example, for Vodafone Italy, Huawei’s vIMS Core and Nokia Networks’ virtualized Application Server (vAS) are both supported by their own virtual network function managers (VNFMs), apparently with no overarching NFV orchestrator (NFVO) functionality. So what about provisioning and assuring the VoLTE service across them both? And for China Mobile, Alcatel-Lucent’s vIMS Rapport is contracted for several provinces and cities where Huawei’s traditional (i.e., non-virtualized) IMS is also contracted. So how will these virtual and physical network functions be orchestrated together?

There are sure to be good answers to all the questions raised by these announcements, but the overwhelming takeaway is that these carriers have committed to the vVoLTE road and are pushing the NFV envelope forward as fast as they feel that they confidently can. That confidence is also an endorsement of their vendor partners. From a Current Analysis’ perspective the telco’s “path to the cloud” just stepped up a gear.

Leave a Reply