Arista Networks today unveiled its next-generation 7130 series switches purpose-built to accelerate adoption of 25 Gb/s Ethernet speeds (known as 25G) in financial market networks.

With the rapid growth in market data volumes, legacy 10G infrastructure struggles to handle traffic spikes. Arista's goal with its new 7130 system is to future-proof networks for ultra-low latency trading needs.

The 7130 series consists of three new systems optimized for 25G performance — the 7132LB, 7135LB and 7130B-32YD models. Arista claims the new switches deliver 2.5-times bandwidth versus 10G to minimize queuing delays during market data surges. Latency reaches as low as 150 nanoseconds for layer 3 forwarding.

"10G is becoming a bottleneck for many markets," Martin Hull, VP of cloud and platform product management at Arista Networks, told SDxCentral.

Hull noted that in the past, financial markets and traders have pushed back on 25G networking because of a lack of low-latency 25G L1 hardware and the overhead of forward error correction (FEC).

"With these new product introductions, Arista has solved the major impediments to broader 25G adoption in the financial markets," he said.

Why 25G provides a better networking option than 10G link aggregation

10G links have long been the standard for many network use cases. To date, 10G link aggregation, where multiple 10G links are grouped together, has been a somewhat effective approach for growing bandwidth needs.

Hull noted that parallel links with link aggregation groups (LAGs) are an effective approach to reducing network congestion, assuming you don't run into hash collisions, and may still be used in the 25G world.

"25G has the advantage of reduced serialization delays, which also translate into reduced queueing delays when network congestion does occur," Hull said. "A single 25G link is also easier and less expensive to deploy and manage than two to three 10G drops."

How Arista is enabling 25G for ultra-low latency and market data networks

25G networking is not a new thing. In fact, Arista was a founding member of the 25G Ethernet Consortium back in 2014 when it began the effort to develop the new networking technology.

The speed benefit of 25G on the wire is a function of the increased clock rate and isn't specific to anything Arista is doing. However, Hull explained that 25G at longer distances usually requires FEC, which can add up to 250 ns of latency, negating the benefits of the reduced serialization delay.

"Our enhanced performance optics have higher specifications that enable FEC-free operation while remaining standards compliant," Hull said. "Removing FEC from the equation substantially improves the latency of an end-to-end 25G solution."

The Arista approach also deals with the application side of 25G, where Arista develops FPGA applications like SwitchApp and MultiAccess to support 25G with optimizations to minimize latency. Hull said that most switch silicon these days is designed with flexible pipelines that are great for feature development, but add significant latency.

"By designing a latency-optimized 25G pipeline, we can switch 25G much faster than typical ASICs," he said.

Image source: Arista Networks.