SEATTLE -- OpenDaylight Summit -- The current virtual network functions are still too much like snowflakes at a time when the telecom industry needs Lego blocks, AT&T's Chris Rice told the OpenDaylight Summit here Tuesday.
AT&T Inc. (NYSE: T) has actually been working with SDN for decades, the senior vice president of AT&T Labs noted, and is at the point where it needs re-usable, interoperable VNFs to continue pushing forward with its network plans.
"The VNFs we get today are too special, they are too unique, they are like snowflakes, and we want Lego blocks rather than snowflakes," Rice said. He provided a basic set of functions -- configure, test, scale, start, stop, rebuild, restart -- that every VNF needs to have, adding that these are commodity things and not issues on which AT&T will be making buying decisions.
"It is to the whole industry's advantage to normalize those," Rice said. "For SDN really to deliver on what we need it to deliver, that is a key function that has to occur. Move the VNFs from snowflakes to Lego blocks -- and, if you remember from the old days or you have kids like me that play with these, Lego blocks are different sizes, different shapes, different colors -- not the same but they all interoperate."
"What this is, is an ability for you to bring signaling in on a particular wavelength or on a particular piece of optics and to be able to change that as you go through the different parts of the network," he said. "The great thing about this this is not something that is virtualized -- this is a PNF -- physical network function as opposed to a virtual network functions.
"That didn't stop Martin and his team from creating an excellent abstraction of this within Yang, so really well-defined as are the interfaces and APIs associated with it, as is the data telemetry associated with it," Rice said. "So when we talk about moving from snowflakes to Lego blocks, Martin and his team did a great job."
Rice stressed that AT&T is using SDN and the OpenDaylight controller not just in Layers 2 and 3 of the network, where SDN is most frequently discussed but in the physical layer and in the upper application layers as well, with its Application Controller. He pointed to ECOMP, the enhanced control, orchestration and management platform that AT&T is moving into an open source project, and the critical role ODL-based controllers have in enabling it to function as a production platform today.
AT&T has gleaned other key lessons from real-life experiences in SDN such as its router farm controller, which was critical in allowing AT&T to easily change out edge routers when one router was nearing end-of-life status and tens of thousands of deployments needed to be changed out. The company was even able to change vendors, moving the configuration data from one vendor's gear to another, over that massive footprint, and had only two routers fall outside the expected maintenance window, Rice said. Key lessons from that process included the critical role of proper modeling, and that signaling, while necessary is not sufficient; you also need configuration, resource management and analytics, he said.
Rice said AT&T has chosen to use ODL's open source controller because of its broad protocol support and the recognition that brownfield deployments also need support. He also harkened back to what he feels is AT&T's first real SDN effort, back in the time-division multiplexing days when intelligent networks were created, initially to support 800-services.
"At the time, no one was really aware of all the growth that would result from that," in customer care and more, he said. "That was a multi-billion-dollar industry. You might want to ask yourselves, are we on the precipice of doing something right now, with what we are doing in OpenDaylight."
— Carol Wilson, Editor-at-Large, Light Reading