Over the last couple of years, Intel has been working on the Rack Scale Architecture (RSA), a next generation data center architecture incorporating software defined elements. Intel RSA plugs a gap in the Facebook’s Open Compute Project in the areas of power and cooling at the rack level, where Intel designed an efficient power and cooling system for the entire rack. In a nutshell, RSA architecture logically breaks the compute, storage and network resources into three separate layers. Each layer of resources, such as compute can be pooled together to offer better efficiency, and lower total cost of ownership.
What does this all mean to the CDN? Really nothing on its own, but now that Ericsson has created the Hyperscale Data Center System (HDS) 8000, the first rack scale design on the market, its likely to have a significant impact in the years ahead, as this technology matures. The HDS 8000 is a pre-loaded rack that comes with all the hardware and software components to power cloud infrastructures. Ericsson decided to use Pluribus Networks “Netvisor” as the switch fabric in the HDS, thus Pluribus is the bridge that links Intel and Ericsson to the CDN industry. CloudFlare standardized on the Pluribus Network switch for all of its PoPs.
Pluribus competes against Arista Networks, and in CloudFlare’s case, Pluribus replaced the Juniper TOR switches because they were dropping too many packets, due to their shallow buffers (9MB). Ericsson comes into play, because they are a global leader in Telecom and Mobile infrastructure, especially optics, and optics is a game changer in the SuperRack, as discussed below. Ericsson designed the HDS rack which incorporates optics instead of copper – because cooper is the bottleneck when it comes to I/O throughput. According to Sunay Tripathi of Pluribus Networks, all of the I/O has become the bottleneck, including “Ethernet, PCI-Express, and SATA Cables”. The reason copper is used because its cheap, but it doesn’t scale well above 10Gbps. Ericsson has changed the equation.
Optical vs Copper
Ericsson has introduced optical interconnects into the RSA architecture via HDS 8000, which replaces copper components used in I/O, and incorporates Silicon Photonics. A single Silicon Photonics chip “can support 100Gbps transmission on a chip less than half the size of a postage stamp”. Silicon Photonics equates to using light, and according to Max Smolaks, “using light instead of electrons” means that “speeds of up to 800Gbps can be reached in each direction'”.
Although RSA is a new architecture on the market, it seems very promising and has the potential to become the new SuperRack in the near future. And what is a SuperRack? It is a rack full of high performance bare metal hardware with a ridiculous amount of RAM, SSDs, CPU Cores, and soon to be 100Gbps NICs that can support the content delivery needs of a medium size city like San Diego. Maybe 🙂