Carrier network virtualization service ConteXtream has tossed out its proprietary controller in favor of one based on OpenDaylight. The company on Tuesday launched ContexNet 4.0, the first version of its carrier network overlay to build on the OpenDaylight open source controller platform.

An early pioneer in software-defined networking (SDN), ConteXtream deployed its first carrier network virtualization service in 2008 — the prehistoric era when it comes to SDN. The service has since found major customers worldwide, including US-based Comcast and GrameenPhone, the Bangladesh telco claiming 50 million subscribers.

The new ContextNet 4.0 service aims to provide carriers increased subscriber awareness (that is, tagging traffic to a specific subscriber) and facilitate the use of network function virtualization (NFV) to quickly spin up new subscriber services.

In addition to implementing OpenDaylight for the service's SDN controller, ContextNet 4.0 uses OpenFlow switching protocols and integrates with the OpenStack cloud orchestration platform—a vote of confidence for the two prominent open source projects.

Mountain View, California-based ConteXtream has contributed code to OpenDaylight since the project's inception in 2013, welcoming the move toward collaboration on SDN standards and platforms, says Anshu Agarwal, vice president of marketing at ConteXtream.

"When we stared we were alone—it was very lonely," says Agarwal. OpenDaylight, she adds, "is taking in so much brain power from so many people that we decided we had to be part of it. We realized there is no point of doing those things in a proprietary system, so why not leverage what's happening and why not contribute to it?"

As carriers search for new revenue streams in an increasingly tight market, the flexibility to experiment with new service offerings has begun to outpace capital expenditure savings as SDN's chief selling point.

Premium subscriber services could be the key to new revenue for carriers. For example, a self-serve parental control feature could be much easier to deploy using SDN, which can direct web traffic from a child's phone through a virtual firewall, rather than running all network traffic through parental control filters and plucking out traffic only for enrolled users.

"Back in the 80s, carriers had a lot of innovation in their own labs," Agarwal says. "Then internet era came, and that innovation moved out to companies like Cisco and Juniper, so carriers were left out in controlling that innovation."

"With the advent of SDN and NFV, I think carriers are starting to feel that they can control what they put in the network again."