Comcast finally unveiled its long-promised cellular wireless service, which will piggyback on Verizon’s cellular network through a five-year-old mobile virtual network operator (MVNO) agreement.

Comcast’s cellular service, Xfinity Mobile, is available only to subscribers of other Comcast services and so might be less interesting from a market standpoint than it is for what it says about the evolution of communications networks.

The convergence on IP networking and all that has entailed – virtualization, the development of cloud-based resources, software-defined networking (SDN), network functions virtualization (NFV) – is making it technologically easier for companies with disparate wireline, wireless, and satellite networks to rely on each other to fill gaps in their respective service bundles.

Cable has always had a fitful time with cellular services. In 2006 Comcast, Cox, Time Warner Cable, and Advance Newhouse (those latter two now both part of Charter) entered a wide-ranging deal with Sprint that included an MVNO component. Based on that, Comcast offered a short-lived cellular service called Pivot that it pulled off the market in 2008, shortly after introducing it.

Cox Communications built its own cellular network, but could not sustain it. It pulled the plug on that effort in 2011.

That same year, Comcast and Charter Communications both signed MVNO pacts with Verizon. The deals were known to be restrictive in terms of the plans and services the cable operators could offer, but had either MSO become desperate for a cellular service in its bundle before now, it could have had one.

Instead, cable concentrated on WiFi and helped make it even more pervasive – though only indoors – though that’s where most phone calls are made. Cable’s WiFi strategy helped make dual mode cellular/WiFi handsets practical. It got cable into wireless telephony, and traditional wireless operators tolerated the trend – if not embraced it – because it relieved pressure on wireless networks they’ve been complaining are overburdened.

At the same time, traditional wireless carriers are coming to rely more on cable companies to perform cellular backhaul for them.

IP convergence might be such an entrenched trend that it’s become something of an afterthought, but it’s the thing that allows rival service providers to cooperate to the benefit of their respective customers.

When communications services companies adopt virtualization strategies, they are doing so in part to enable their business customers to automatically order and provision services, regardless of whether those customers are manufacturing companies, financial companies, biomedical companies, or another communications company.

Comcast’s MVNO service is just another piece of evidence that communications companies are now among each other’s biggest customers, with opportunities to take advantage of virtualization not just as enablers but as customers too.

In a similar vein, Charter recently said it began testing 5G network technology and expects to introduce its own branded cellular service based on its MVNO agreement with Verizon next year.