AT&T has led the charge in contributing inhouse developments to open source processes, in a bid to accelerate adoption of new software-driven network technologies, and increase its own influence over the whole ecosystem. But it is not the only carrier to take this approach. A smaller US player, CenturyLink, told the recent Open Networking Summit that it is planning to donate part of its NFVi orchestration process to the open source community.
Adam Dunstan, VP of SDN/NFV engineering at CenturyLink, said that his team has extracted the Service Logic Interpreter from a module of the ONAP (Open Network Automation Protocol) platform. ONAP is one of the Linux Foundation-hosted systems which is largely based on AT&T code (along with ORAN and the dNOS white box operating system).
CenturyLink then repackaged that logic as part of its NFV orchestration process, taking it out of OpenDaylight, and back into Java. It codenamed the result Victor, and will release its work into open source, probably to ONAP.
Despite that, the operator is not planning to join ONAP formally. “We continue to consider it, but we haven’t used a lot of the tooling and so if you are not really using the tooling then it limits the benefit of joining,” Dunstan said in an interview. “ONAP is a big complex system and putting aside opinions on the whole thing, CenturyLink already has a big complex system. Getting it all to fit together is a challenge.”
In addition, CenturyLink recently acquired Level 3, and has those systems to integrate too, so “adding another whole thing doesn’t make sense. We have to get much more granular about what we do.”
Victor is a microservice that runs inside containers and its job is “to do one thing and one thing well – spin up something automatically and let the system know that happened, and then his job is done,” Dunstan said while presenting the code at the conference. This uses the same tooling as ONAP to enable operators to create a service model, which then generates an associated user interface and web services.
While CenturyLink may not be joining ONAP full time yet, its collaboration with the organization shows one of the benefits of ONAP – the ability to use it in a very modular way depending on an operator’s requirement. CenturyLink has chosen to break up the orchestration process rather than using a single master orchestrator for everything. Dunstan explained in his presentation that it has created separate domain orchestrators, – one for virtual network functions and another for physical network functions, and a third for third party assets like transport. These three domain orchestrators are coordinated by a master orchestration layer.
CenturyLink has been working on a virtualized network platform since 2011. In 2012 it announced its Programmable Services Backbone architecture, based on VMware, and that was followed by a complete virtualization stack, based on OpenStack.