It seems well accepted that 5G cellular networks will benefit from features related to software-defined networking (SDN), but that doesn't mean mobile operators have to wait for 5G to grow up.

NTT Docomo has plans for implementing a virtual evolved packet core (vEPC) in “fiscal 2015,” as Hiroshi Nakamura, the carrier's senior vice president, outlined in a Wednesday keynote at the SDN & OpenFlow World Congress. (NTT's fiscal year ends in March; I'm presuming Nakamura was referring to the current fiscal year, which U.S. companies would term “fiscal 2016”).

“SDN and NFV — we can apply this immediately on the networks,” Nakamura said. “Of course, this is very important for 5G, but we do not have to wait for 5G.”https://www.sdxcentral.com/flow/sdn-software-defined-networking/

Docomo discussed its vEPC plans in March, announcing that it had picked Ericsson, Fujitsu, and NEC for the deployment.

Docomo talked about these plans during last year's SDN World Congress. Then, the company named several vendors being considered for vEPC work, including Alcatel-Lucent, Cisco, Huawei, and Nokia, as well as Ericsson and NEC.

The vEPC is a well known NFV use case. Most, if not all, mobile-network equipment providers have some kind of vEPC offering, and at least two startups have found some success with the concept. Affirmed Networks was named a Domain 2.0 supplier by AT&T last year, and Connectem was acquired by Brocade.

Lately, though, most of the chatter has been around the 5G network, the standards for which are still in progress. Concepts such as the cloud RAN and promising features such as network slicing are making SDN and NFV ubiquitous in 5G conversations.

NFV lends itself to multivendor deployments, but to make that work, the industry should nail down standards for some of the interfaces in the architecture, Nakamura said.

Specifically, he was thinking of the interfaces into and out of the VNF manager. Part of the NFV framework defined by the ETSI Industry Specifications Group (ISG), the VNF manager talks to element management systems, the virtualized infrastructure manager (VIM), and an orchestrator.

Nakamura would also like to see any NFV architecture take advantage of the OSS and BSS systems already in place, to minimize the impact to operations. That makes the interface between the orchestrator and the OSS/BSS — an interface the ETSI ISG calls Os-Ma — quite important, he said.