Striking Gold with Copper in the Data Center
10G Ethernet (10GbE) is a very popular interconnect technology in today’s data center. It’s widely used for servers/storage devices connecting to top-of-rack (leaf) switches, as well as connecting those leaves to the aggregation (spine) switches. According to a Dell’Oro Ethernet Switch Market report published in 2014, 80% of server connections will be 10GbE-based by 2018.
In general, two types of physical media are used in 10GbE interconnects: fiber and copper. For intra-rack (server/storage to leaf switch) connections, most deployments use copper cabling as it is the most cost effective for short distances within the rack.
There are two copper cable types: twinax and twisted pair. Twinax is used in the 10GBASE-CR standard in the DAC (direct attached cable) format, which is a fixed length cable with SFP+ plugs integrated into both ends. Twisted pair, on the other hand, is something that should be very familiar to every IT person. Remember CAT cables and RJ-45? The 10GbE interconnect standard that uses twisted pair is 10GBASE-T, which is officially defined in the IEEE 802.3an standard.
10GBASE-CR with DAC is great and used in many deployments. However 10GBASE-T over twisted pair offers some unique benefits:
Distance & Interoperability
10GBASE-T over twisted pair Continue reading