Verizon may have been quieter about its white box and SDN (software-defined networking) strategies than AT&T, but it share its rival’s ambition to transform its costs and efficiencies by deploying disaggregated, virtualized platforms everywhere. Indeed, it is further advanced than AT&T in one critical area at least, convergence, having merged its wireline and wireless operations as well as its next generation architecture.
However, while AT&T has used the SDN program to shake up its supply chain, Verizon has been more cautious.
AT&T has developed key software elements, and hardware reference designs, inhouse – sometimes with unfamiliar vendor partners – and donated some of that work to open initiatives like the Linux Foundation’s ONAP and O-RAN, or Facebook’s Open Compute Project. It has worked with big names like Broadcom (for white box switch-chips) and Cisco, but also with new ones, like Barefoot and tail-f. Of course, the common fate of open new ecosystems is epitomized by those examples – Barefoot was acquired by Intel after getting the AT&T support, while tail-f was acquired by Cisco itself.
Verizon has stuck to its traditional approach to a new network generation – gathering a group of familiar vendors around itself, and providing a heavy level of direction of their work, so it ends up with a semi-customized platform. It did this in its CDMA RAN at the start of the century, in its IMS (IP Multimedia Subsystem) a few years later, in its pre-standard 5G network, and is doing the same in key elements of its virtualized network. It’s an approach that is more common in Asia, and is very different from that of AT&T (and Sprint, before it was acquired), because while both telcos have large engineering resource and a high degree of control of their suppliers, Verizon does not often share the results far and wide.
That inclines it to stick with familiar suppliers, even for disruptive open architectures, though on the enterprise side it has introduced a more diversified bunch of companies to support its Virtual Network Services (VNS) portfolio. This is a catalog of virtual network functions, including SD-WAN, security and others, that enterprise customers can deploy on white box universal CPEs. Lanner Electronics of Taiwan was an early uCPE addition to the VNS family, highlighting the potential to introduce low cost hardware suppliers to enterprise and, eventually, carrier networks – leveraging the all-important economies of the Taiwanese ecosystem.
So it seemed almost like a step backwards when Verizon added its latest white box option for VNS, the Cisco 5000 Series Enterprise Network Compute System (ENCS). Like the other uCPE options, it will be tightly integrated with Verizon’s core network and BSS/OSS to provide enterprises with access to a fully automated service for configuring, orchestrating and managing NFV workloads.
Of course, Cisco can hardly be ignored by an enterprise service, since many customers will want a turnkey Cisco environment. But as with telco networks, so for larger enterprises, truly commoditized hardware and a fully open environment often bring too many compromises in performance. So JL Valente, VP of product management for managed services at Cisco, explained: “It’s an x86 platform, but it’s an x86 platform that is built with a purpose specifically for enterprise-grade NFV”.
Getting the balance between full openness and full carrier-grade performance is the central conundrum of the migration to disaggregated, cloud-native networks, and it explains why progress often seems slow at the large operators, even when they have set out ambitious goals.
Virtualization/SDN, together with convergence, are cornerstones of Verizon’s publicly discussed strategy to transform its cost base and its services, and are particularly important for an operator which has built its network from a conglomeration of systems acquired over the years – local telcos and MNOs, long distance carrier MCI, Verizon Wireless (itself with roots in AirTouch and the Baby Bells), Alltel, and others.
It is in the process of converging many of its wireless and wireline operations, and working on a converged core network, while looking to leverage the same fiber, as much as possible, to support consumer, enterprise and city broadband, as well as backhaul for dense urban networks and fronthaul for distributed RANs.
None of this will happen quickly, and given what is at stake, it is unsurprising that Verizon should be cautious about shaking up its supplier relationships at the same time as everything else. In 2018, it revealed that it was using SDN to combine all its existing service edge routers for Ethernet and IP-based services into a single platform, and that this architecture would be expanded to other services and components in future. The telco has decoupled the edge routing platform from the control plane, and the latter has been moved to general compute servers, which Verizon says will enhance its capabilities beyond those of a traditional router.
The new multi-service edge solution was created in partnership with Cisco and Juniper Networks, two stalwarts of the Verizon network, and the deployment is only one step towards a true white box strategy. Cisco’s and Juniper’s software is decoupled from the hardware, but the hardware remains specialized, running on dedicated ASICs rather than merchant chips.
Michael Altland, director of network infrastructure planning at Verizon, acknowledged at the time that there was still some way to go to achieve a true white box environment. He said: “It’s not true white box where you are running merchant silicon. It’s still custom silicon and controlled by that vendor’s software, but they are no longer tightly coupled in terms of if you run out of control plane resources you exhaust the entire router. Now I have the flexibility to scale the control plane separately from the hardware.”
This halfway-house approach, reliant on traditional vendors, remains in play in Verizon’s main network. And its broader SDN strategy has been the same mixture of open ambitions combined with safe vendor choices.
Back in 2015, it announced its initial SDN roadmap for fixed and mobile networks, and then a year later, it signed up for the Open Networking Foundation’s (ONF’s) ONOS project, aiming to accelerate its network transformation by using open source network operating system. However, Verizon did not emulate AT&T by shaking up its supplier roster – the framework architecture and interface specifications were drawn up by entrenched suppliers, Ericsson, Nokia, Cisco and Juniper. Verizon said smaller players would then be invited to work within that framework, increasing the list of SDN partners to about 20 by roll-out, but it is not clear how far that policy is now being implemented.