SANTA CLARA, Calif. — Less than a year after 100-Gigabit Ethernet was standardized, an industry group is considering a set of specifications that might make the high-speed technology less expensive and more useful.
The IEEE 802.3 100-Gigabit Backplane and Copper Cable Study Group of the Institute of Electrical and Electronics Engineers isn’t trying to change the 100 GE standard but to make it easier to build modules with more 100 GE ports, according to John D’Ambrosia, who is chairman of the new group. Its first meeting took place last month. D’Ambrosia spoke on the sidelines of the Ethernet Technology Summit on Tuesday in Santa Clara, though he emphasized that he was not speaking on behalf of the study group.
The effort to develop specifications for 100 GE backplanes, which provide the connections within a switch, comes as the IEEE also starts to explore the possible need for an even faster standard. An ad hoc group will begin meeting to study users’ current bandwidth requirements, which could help determine the demand for a version of Ethernet above 100 G bps (bits per second). But while a new speed record may be enticing, network engineers in the real world need to wire their data centers at low cost and be prepared for future needs, according to D’Ambrosia.
“Everyone wants the bandwidth, but they also want the bandwidth at lower and lower cost,” D’Ambrosia said. “People just don’t have money to throw around.”
Today, some 100GE LAN interfaces are on the market, but they only come with one or two ports per line card. Every inch of space on a switch chassis and every bit of floor space in a data centre is very valuable, so dedicating a whole card to one or two ports is an expensive proposition, even apart from the actual cost of a 100 GE interface. A module with several 100 GE ports would probably be a better value as well as more useful, D’Ambrosia said.
As an example of 100 GE pricing, Juniper Networks Inc. typically charges ten times the price per port of 10-Gigabit Ethernet, so a 100 GE port may cost about US$150,000, though prices vary, said Luc Ceuppens, vice-president of marketing for platform systems.
A key challenge to increasing the port density of 100 GE switch modules is that the current technology for connecting an interface module to a switch chassis typically won’t support more than one or two 100GE ports, D’Ambrosia said. Current technology won’t scale beyond that. Virtualization has made the problem even harder, because a data center full of virtualized servers tends to use the network more intensively, he said.
At the same time, the first-generation 100 GE ports and line-card components themselves are fairly large and power-hungry, he said.
As with earlier technologies, standardization of the backplane should help 100 GE move beyond proprietary designs and create a larger ecosystem of component vendors, eventually driving up production volumes and lowering costs through economies of scale, D’Ambrosia said. Power requirements also are likely to be driven down, he said.
The backplane group is also considering a new specification for a narrower cable interface, which should also help to save space in equipment designs and could lead to more flexible copper cables linking servers with data-center switches, D’Ambrosia said.
