SAN JOSE, Calif. — Broadcom will nearly double the density and memory in its next-generation Ethernet switch in response to the rising size and complexity of data center networks. The Strata XGS Tomahawk packs 7 billion transistors and 480 Mbits memory into a chip aiming to keep pace with the trend toward software-defined networking.
Big data center operators such as Amazon, Google, and Facebook are calling for ways to speed and simplify their rapidly expanding networks. They are driving the industry to an emerging class of network virtualization protocols and chips that must deliver both significantly more bandwidth and more flexibility.
In response, market leader Broadcom said it is sampling Tomahawk, a chip that sports 128 25 Gbit/second Ethernet ports and new capabilities for tracking packets. Rival Cavium recently announced its Xpliant chip with similar targets and bandwidth, but it has not yet taped out.
Broadcom has a time-to-market advantage based on a proven architecture, but Cavium will have a unique capability to more quickly support new protocols in a high bandwidth chip, said Bob Wheeler, senior analyst with The Linley Group in Mountain View, Calif. Both face hurdles.
The 7B transistor Tomahawk is the latest member in Broadcom's ten-year Ethernet switch road map.
"It's likely to take a full year to get a device of the Tomahawk’s complexity to production," Wheeler said. Meanwhile "Cavium's chip depends a lot on the software which they have been writing from scratch," he said.
Wheeler gives Cavium an edge in responding more quickly to the many emerging protocols for software-defined networking. "Virtual networks are evolving at the pace of software, so if want to terminate a protocol in a top-of-rack switch you need that feature in silicon and you don't want to have to wait," he said.
Rochan Sankar, a director of product marketing for network switches at Broadcom, countered that there are only a few major new protocols in the works and they are being defined "on a time scale of a few months to a few years."
For example, carriers are developing the so-called Network Services Header. The Open Networking Foundation is said to be at work on a major overhaul of its ground-up effort, OpenFlow. Meanwhile Geneve, a new overlay standard for existing networks, is in the works and could replace the existing VX-LAN and NVGRE overlays.
Tomahawk supports NVGRE and VX-LAN, specs which Broadcom co-authored and are still in early phases of adoption, said Sankar. The chip also supports a number of other protocols including today's OpenFlow 1.3 which Broadcom supports in software that is now in test clusters with plans for use in production nets, he said.
Broadcom would not say how much Tomahawk will cost or when it will ship. However it said production usually follows within a year of sampling. The 28nm Tomahawk is somewhat larger than its current 40nm Trident II+ switch and fits into a "similar-sized package," it said.
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