Marian Croak on why and how AT&T is moving to SDN, NFV and an all-IP future with Domain 2.0

with Marian Croak, senior vice president of Domain 2.0 architecture and advanced services development, AT&T

Marian Croak


with Marian Croak, senior vice president of Domain 2.0 architecture and advanced services development, AT&T

AT&T Mobility's (NYSE: T) "User-Defined Network Cloud" initiative, which makes use of Software-Defined Networking and Network Function Virtualization, is aimed at transforming the carrier's network. AT&T wants to virtualize hardware functions, cut costs and put more control of its network in the cloud and in the hands of users, both in the consumer and enterprise markets. Recently, at AT&T's "Innovation Showcase" in New York, FierceWireless Editor Phil Goldstein spoke with Marian Croak, senior vice president of Domain 2.0 architecture and advanced services development, about these initiatives. Croak talked about the importance of SDN and NFV, what vendors need to do to be a part of the initiatives and why other carriers should get on board. The following is an edited version of their conversation.    

FierceWireless: Why are Domain 2.0 and the User-Defined Network Cloud so important for AT&T?

Croak: As you know, we have to change from our TDM-based network to an IP network and we have made great strides in doing that. But we have some services they haven't done the full transition. And by the year 2020 we expect to be an all-IP network. So what type of IP network do you want to become? User-defined network, or the Domain 2.0 program, is defining the type of network that will be.

And what we're actually doing is going through sets of iterations or progressions to get to that, and those are called beachhead programs. And some of those beachhead programs will be released later this year, and they'll be progressive in nature. And then by the time we get to 2020, we'll be at the end of it.   

FierceWireless: Why is it important to group the Software-Defined Networking and Network Function Virtualization initiatives together?

Croak: In order to really have a programmable network you need to have a programmable controller. And that controller has to interface into things like policy engines and orchestration capabilities in order to know who can use it, how they can use it and what capabilities may be available to them. To make the capabilities available, we need network virtualization. So that means just abstracting functions that used to run in hardware and putting them into software. The fact that they're virtualized means you can actually put them in a cloud. And in order to replicate them or increase their capacity you can spin off virtual machines and replicate them in those machines.

SDN is the software-defined network piece of it and that's where you really have the controller. And the NFV part of it comes in where you virtualize the capabilities that are necessary to provide, in terms of repositories or catalogues or libraries, and make available to users through the SDN controller.

FierceWireless: We keep hearing that SDN and NFV combined are going to revolutionize the way networks are designed and deployed. That sounds like a lot of hype to me. Is it more than hype?

Croak: You're not a supplier! If you were a supplier you'd know it wasn't hype. That's why these beachhead programs are important. I think you will see us rolling out things within the year. It's May now, so we're talking about months. So definitely more than hype. It really is very disruptive technology in terms of the supply chain. And so they see it more than hype. They have to change in very fundamental ways.

The way that we used to work with the supplier community was that they would build specialized, proprietary hardware that was tightly coupled with software. They have to break that apart now and run software on commodity hardware, which we call white boxes, which are a lot less expensive than what we used to have. And then they have to virtualize their software.

FierceWireless: What are some of these beachheads?

Croak: They're both in the consumer and the enterprise space. I'm going to talk in general just so I won't be pre-announcing anything. In the enterprise space, as you think about what AT&T traditionally has sold to enterprises, it's private networking. You started out with analog, private lines, then you went to packet switching, you had ATM, frame relay and virtual circuits, [and] then IP came into place. And the de facto standard became virtual private networks through IP using MPLS technology.

One of the most important beachhead programs we'll be releasing later this year is a programmable VPN. So instead of AT&T doing all of the provisioning--providing you with new capacity, providing you with new features--we'll be able to program the VPN itself so that if there is new capacity that is needed you could spin it all in virtual machines. You could have service-chaining functions done so you can have--this is over time--QoS, additional bandwidth given to you. 

FierceWireless: In terms of these beachheads, is enterprise going to be on equal footing with the consumer side?

Croak: I think it's going to be on equal footing.

FierceWireless: Moving to SDN/NFV requires giving up hardware and legacy, hardware-based jobs. How big of a problem is that and how does a carrier, especially of AT&T's size, break that apart?

Croak: That's a very insightful question. And it gets at what I think is one of the most important parts about this change. It's cultural. [AT&T network chief] John Donovan calls this a "skills pivot." We may be doing many, many different things in order to effect that. There will be courses for people to take to understand these new technologies and the speed at which we have to deploy them. There will be an intense hiring program for external people to come in, and new compensation packages to attract them and to retain them. That's why a lot of the work we're doing is going on in the Foundries, which we find much more appealing to new recruits.

FierceWireless: What are the common traits among Domain 2.0 vendors that have made AT&T comfortable in selecting them?

Croak: You'll see more announcements coming out as well, both from traditional vendors as well as much smaller vendors. One of the most important things is we want to adhere to open-source software. We want to make sure these vendors are relying on commodity-based hardware, that they are not building proprietary systems, that they can be very flexible and adaptable.

FierceWireless: What exactly is AT&T doing with these vendors? Are you actually deploying their software/services/equipment in commercial markets or mainly engaging in lab work for now?

Croak: We're doing both, and we're doing many different types of lab work. We're testing out things to make sure they are not just slide-ware, and we're taking them through all the rigor that you would normally do to make sure these products actually work. And then, as I said, we are actually using some of these vendors today for the beachhead programs that will go into the field later this year.

FierceWireless: Should we expect more Domain 2.0 vendor announcements this year? And will AT&T eventually have lots of Domain 2.0 vendors or will there be fewer than you had with legacy deployments?

Croak: Yes and yes. We want a very large ecosystem of vendors, both big, traditional vendors but many, many smaller vendors.

Marian Croak on why and how AT&T is moving to SDN, NFV and an all-IP future with Domain 2.0
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