"We're building the foundation right now," he says. "Once we build in the automation and start maturing our sandbox our incubation and certification environment next year in 2016 we will ramp up significantly."
AT&T is keeping score by determining how technically- and production-ready 200 target VNFs are. Once determining which services make the 200 VNF target list legacy services like ATM, frame relay and TDM voice will not AT&T evaluates the degree to which each is virtualized, under SDN control, and integrated into the carrier's Enhanced Controller Orchestration Management Policy (ECOMP) operations management framework.
ECOMP "gives us a greater degree of automation and autonomous control," Fuetsch says.
AT&T Labs developed ECOMP's policy engine. Differentiation is why AT&T developed its own instead of adopting something like OpenDaylight's Group-Based Policy model.
"A lot of our secret sauce makes our architecture unique and differentiates it from the others," Fuetsch says.
The VNFs also have to be capable of passing live traffic or workloads, he says. Once 75% of those 200 VNFs hit those virtualization, programmability and live traffic prerequisites, AT&T will have hit its 75% virtualization milestone.
But VNF suppliers also have to meet stringent requirements. Of the 10 announced Domain 2.0 suppliers to AT&T's SDN project, only four so far have made the sandbox to put their products through a rigorous set of virtual network guidelines and requirements, Fuetsch said. He declined to say which ones.
And in terms of customer-facing VNF services, AT&T's Network On Demand is an SDN back-ended offering rolled out in 100 markets. It uses Brocade's OpenDaylight-based Vyatta controller as its brains.
AT&T's MVNO service for resellers is based on Affirmed Networks' evolved packet core and controller. All three controllers Affirmed, Vyatta and ONOS might converge onto one overall master controller for the entire service network over time, Fuetsch says.
ONOS might have the inside track.
"OpenDaylight is much more of a grab bag," Fuetsch says. "There are lots of capabilities, a lot more contributions have gone into it. ONOS is much more suited for greenfield. It takes a different abstraction of the network. We see a lot of promise and use cases for ONOS in the access side with a virtualized OLT as well as controlling a spine/leaf Ethernet fabric. Over time ONOS could be the overall global centralized controller for the network. But because we have the existing network brownfield — we have to coexist" with other controllers. "ONOS is still maturing."
Though leaning heavily towards open source, AT&T is also evaluating roles for Cisco's Applicatiuon centric Infrastructure and VMware's NSX controllers. AT&T is using NSX in its data centers but there could be bigger roles for it and for ACI... or not.
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