Arista brings cloud-grade routing to the network edge — Kerravala

Zeus Kerravala

This week Arista Networks announced an expansion of its cloud-grade routing solutions that extends its products to the edge. Arista has added new features to its EOS operating system to enable its products to be used as edge routers, including new capabilities for virtual private networks (VPN) and traffic engineering.

Arista is best known as a switching vendor, but it has been growing its routing business since 2016 when it introduced its Broadcom Jericho based R-Series products with its Flex-Route technology. This enabled Arista to support a full internet routing table in merchant silicon.

It’s important to understand that while Arista is expanding its routing solution, the company does not build routers. Rather, it’s delivering routing capabilities in its R-Series switch. Arista isn’t the first vendor to try this. A decade ago, Foundry and Force10 both built switches that had carrier grade routing but both vendors failed in their attempts to upset the router apple cart. There were a number reasons for this, including market readiness, but the biggest issue was that, a decade ago, switch-based products didn’t have the horse power required to replace a router. Merchant silicon has come a long way since then, making the option more viable.  

The other major change in the industry that enables Arista to push into routing is the convergence of network protocols to Ethernet. Switches are great at moving Ethernet packets but don’t handle multi-protocol well, but routers did. Ethernet is now being used to blur the lines between the LAN and WAN as merchant silicon can now provide high density Ethernet interfaces at variable speeds. 

Also, Arista has been careful to never bite off more than it could chew. In 2016, it didn’t try and replace every router, everywhere, as Foundry and Force10 attempted. Version 1.0 of Arista routing was aimed at fairly basic use cases such as peering and internet exchanges.

In 2018, its 2.0 routing stack was targeted at the provider edge, core and content delivery networks. Now it’s focused on winning the edge.

Along the way, the company has had to beef up its routing capabilities. In a briefing, Jeff Raymond, Arista's VP of EOS Product Management and Services, told me that the company has added almost 300 routing features in the past 18 months. He noted that routing customers can still leverage Arista’s single tier Universal Spine-Leaf design (or spline as Arista has called it), but it’s been beefed up with larger memory and table sizes that internet resident routing devices require.

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There has certainly been demand for a switch that could route, as there is an obvious economic advantage as the price per port of a switch is about a tenth of a router. Also, the design of a switch enables it to have much greater port density so, for the right use cases, a telco or cloud provider could save millions in capital costs. As strong as this value proposition is, a switch that offers routing can’t replace a router everywhere. As noted above, a switch is based on Ethernet, so any place in the network that requires multi-protocol support is best served by a router.

Arista is using the term “cloud grade” versus “carrier grade” as it’s bringing its experience with the cloud titans to build next-gen edge locations. Arista told me it has several “wins” with its approach and named Comcast, Connecticut Education Network, CDLAN, Zenlayer and Vocus.

This release is targeted at the multi-cloud edge, metro edge and 5G RAN, each of which is going through an architectural shift that demands simpler design and higher speeds. Of these opportunities, the 5G RAN is the most interesting as it’s an area where Arista’s experience with the cloud providers should prove beneficial as 5G mandates cloud-native architecture. In this part of the network, traditional mobile backhaul is being disaggregated as the public cloud network is being merged with the RAN. The shift to cloud native requires a network that scales like a cloud network with a scale out, repeatable design. Arista’s leaf-spine is ideally suited for this use case. The metro edge has long been shifting away from traditional routers as Ethernet has been the de facto standard protocol for some time.

The additional features for the routing use cases are available now as part of Arista’s latest EOS release. The company also offers a number of form factors for the different use cases. The 7800R3 and 7500R3 are modular systems that scale up to 460TB of capacity. The 7280R3 series includes 1U and 2U form factors used to build a Universal Leaf.

It will be interesting to see how much of a dent Arista can put into the businesses of the router incumbents. Years ago, I was skeptical that Arista could extend its value proposition outside of webscale environments, but it has done a nice job of finding adjacencies where its single OS, simplified architecture and automation capabilities can add value. It’s unlikely the industry will see a wholesale replacement of routers for switches that can route, but Arista should have success in the areas listed above as those are areas of the network being disrupted by the cloud and applying cloud principals to the network is a strength of Arista.

Zeus Kerravala is the founder and principal analyst with ZK Research. He provides a mix of tactical advice to help his clients in the current business climate and long-term strategic advice. Kerravala provides research and advice to end-user IT and network managers, vendors of IT hardware, software and services and the financial community looking to invest in the companies that he covers. He can be reached at [email protected], and follow him @zkerravala and on YouTube.

Industry Voices are opinion columns written by outside contributors—often industry experts or analysts—who are invited to the conversation by Fierce staff. They do not represent the opinions of Fierce.