CenturyLink's Walker on NFV: Just Do IT

CenturyLink's Bill Walker, director of network and cloud architecture, has some advice about implementing NFV for service providers who have yet to set sail on their digital transformation journeys.

CenturyLink Inc. (NYSE: CTL) has been hard at work transforming itself from a legacy telco into an IT-based services company and NFV -- along with cloud and software -- has been an integral part of that digital transformation. While CenturyLink is on its third round of SDN/NFV, it is taking a much more focused approach to reducing complexities in its virtualized platform. (See CenturyLink on Simplifying the Path to Virtualization.)

The nation's third-largest telco is building a virtualized platform that serves not only its needs, but also provides services, such as SD-WAN, that its customers are clamoring for.

In part one of this Q&A with Walker, he spoke about the roles that automation and orchestration play in virtualization. Here in part two, he delves into the lessons that CenturyLink has learned ever since it first deployed NFV back in 2013. In the final installment still to come, he'll speak about the role that open source communities are playing for the industry at large and for CenturyLink.

Telco Transformation: What advice do you have for service providers who are just now thinking about using NFV?

Bill Walker: You may have heard me say if before, but just do it and know that you're wrong. Make your best 70%, 80%, 90% guess as to what scaling, what services and what your market uptake are going to be, and then deploy it. Be ready to pivot. Be ready to admit that you're wrong. What we're seeing is sometimes installing a rack of computers in a central office can take three months.

Reinforce the floor, build a wall, add a fire door and deal with NEBs compliance. If you're ready for it, and you watch the uptake, then you'll know what your expansion's going be. Focus on your top customers and give them what they need.

TT: SD-WAN seems like the perfect example of building a platform to enable a service that businesses seem to understand and want? (See Barrett: SD-WAN Another Brick in CenturyLink's NFV Wall and CenturyLink Throws Hat in SD-WAN Ring.)

BW: Exactly, and SD-WAN was supposed to replace, or erode away, the MPLS business and we're actually seeing that as net new. It's not really eroding potential MPLS business. It actually makes for a nice complement to the existing MPLS services.

TT: SD-WAN has been kind of an entry point for your customers on the way to using SDN. What would be some of the other customer-facing applications or services that you might be looking at or that your businesses would want?

BW: We love SD-WAN, but in reality it's a marchitecture. It's a way to do private networking and fortunately it also exposes a lot of telemetry and control back to the customers. It is something similar to other things we already had. The marchitecture has evolved just based on vendors' competition that everybody has to have. Things like open telemetry and customer side control of the connection are the differentators. It's one thing that we can layer in with some of the physical things we offer like (CenturyLink products) IQ, IQ Plus and MPLS networks, as well as the CPE offerings.

This is one of the first opportunities to really start stacking what people call service chaining although I really hate that term. Being able to stack intrusion detection, denial of service and firewall over private network, which is encapsulating over a more public network. It allows us to wholesale the connection, or take advantage of a connection the customer already has. You get to stay in control of the quality of service and they have the telemetry to read back and see what is manageable. It really offers the customers a lot more open market place, a lot more options and for us it makes the multi-vendor networks more manageable and more... I don't want to say secure. I want to say visible, transparent.

There's another thing about SD-WAN and the update of NFV. If I sell you a one-gig circuit for a branch office, historically I've placed a CPE on your site where I do intrusion detection, denial of service and firewall. That means that your one gig is turning bad traffic, so I'm allowing your one gig to be consumed by a denial of service attack.

If I'm doing that blocking attack lane upstream, let's say at a central office, then your one gig is one gig of good traffic, not one gig of traffic that you're going to end up blocking anyway. Look at SD-WAN on premise or maybe SD-WAN at a central office. If you look at SD-WAN as a private network across multi lanes, it starts to look like cloud connect and it starts to look like colo software-based BPM. Linking a virtual data center across multiple sites in mobile cloud providers and data centers creates a much more software-defined network.

TT: I spoke to BT's Neil McRae recently and he said there needs to be a much bigger emphasis on telemetry. Do you agree? (See Networks Need Telemetry – BT's McRae.)

BW: Absolutely. We don't want to create an environment where we're consuming petabytes of write-only data. It has to be meaningful and we have to apply context, and that does take time and a lot of effort. Where I see it as having real value is when we open the door and start sharing the telemetry with the customers. For example, how our SD-WAN actually exposes some of the telemetry in consumption back to the customers themselves so that we can co-manage the network. I think that's going to carry on even deeper as we look at it, and even go into the more legacy MPLS IQ type services that we offer.

Customers want more visibility and transparency into the telemetry. Obviously, I can't just open the door and share all of my telemetry with everyone. But we need some sort of quality metrics and some sort of reporting against how an incident actually affects a customer. Obviously that's much easier to do when it's software driven.

— Mike Robuck, Editor, Telco Transformation