Versa Networks still isn't talking about its products, but the NFV startup could be found all over last week's SDN & OpenFlow World Congress, whether contributing virtualized network functions (VNFs) to a carrier project or presenting its own spin on virtual customer premises equipment (vCPE).

Versa has been particularly intriguing because of its heritage. Founders Kumar and Apurva Mehta were key figures at Riverstone Networks and played key roles in bringing Juniper Networks to the Ethernet switching market. That's lent the startup some credibility with carriers — note, for instance, Verizon Ventures’ participation in Versa's Series B.

“Not everybody comes to NFV with a service provider pedigree,” said Héctor Avalos, Versa's EMEA vice president of strategy and business.

Versa has said only that it's concentrating on virtual customer premises equipment (vCPE), SD-WAN, and security. But the company has been none too quiet about striking partnerships as carriers and fellow vendors experiment with NFV.

At the SDN World Congress, Versa was namechecked by EMC, which had launched a vCPE-in-a-box that handles functions including policy enforcement for video traffic. Versa also turned up at Orange, which is trialing a self-service portal for a VPN service called Easy Go. Orange's VNF partners include Versa, providing a deep packet inspection engine.

Late in the conference, I'd also been told Versa showed up in Ciena's Blue Planet demo. (While I didn't have time to verify that one, it wouldn't really be a surprise; Blue Planet orchestrates VNFs, so the platform has gathered lots of partners.)

What interested me most, though, was Versa's presentation on Thursday, describing a vertically integrated vCPE that averts the need for service chaining.

Service chains, also called service function graphs, involve creating a sequence of VNFs for traffic to flow through. This is how a virtual firewall and load balancer can be added to an application, for instance.

It sounds like Versa doesn't want to do it that way. All that chaining could add unpredictable latency, Avalos said during his SDN World Congress talk.

“It makes sense for several use cases, but not every use case,” Avalos told me after his talk. For the evolved packet core (EPC) in LTE networks, service chaining is OK, because you don't create an EPC for every user. But vCPE functions need to exist in mass quantities, and users might be prone to activating and deactivating features on the fly.

Without saying that Versa is doing it, Avalos proposed what he called a “vertically integrated vCPE,” one that blinks into existence as a fully formed unit. All the virtual functions reside as roommates in one virtual machine, as I understand it. (Another company pursuing an integrated approach is Clearpath Networks, which uses containers to virtualize its CPE by customer rather than by function.)

Versa seems to be saying it's possible to add and subtract functions from this integrated vCPE without having to respawn the entire virtual machine. How this happens is unclear, and Versa isn't willing to elaborate on it yet.

Addition and subtraction are conceptually easy in service chaining. You can insert a new VNF anywhere in the chain and just redo the networking to accommodate it. (The quick setting-up of arbitrary network connections is what SDN is all about, right?) Inserting something new into an integrated VM sounds dicier. Avalos hinted that Versa will eventually have more to say about this.