The IEEE 802.3 Higher Speed Study Group (HSSG) has decided that
the next speed for Ethernet will be both 40GbE and 100GbE.
Originally the HHSG had planned on doing just 100GbE, but
industry feedback changed the plans somewhat.
“The reason for the two rates is because the two areas of
applications have different growth rates and wouldn’t be properly
services by one rate,” John D’Ambrosia, chair of the Higher Speed
Study Group, told internetnews.com.
“Earlier this year after the decision had been made to choose
the 100GbE rate, individuals involved with the server industry
pointed out that this rate didn’t address the needs of their
D’Ambrosia explained that servers are doubling in their
bandwidth needs every 24 months while core networking bandwidth
needs are doubling every 18 months.
The 40GbE rate is intended to address server and computing
applications and the 100GbE rate is for aggregation and core
For 40GbE, there will be specifications for at least three
physical layers to support 40GbE operations, including at least 100
meters on OM3 multimode fiber; at least 10 meters over copper cable
assembly; and at least 1 meter over backplane.
For 100GbE operations physical layer specifications will include
40 kilometers on single-mode fiber and at least 10 meters over
Though Ethernet is moving to both 40GbE and 100GbE, it won’t be
moving with two different standards.
“We’re going to develop one amendment that will address both
rates,” D’Ambrosia said. “Whether it’s a throttle down or if it’s
just the number of lanes, it will still be one specification that
this project will develop into both speeds.”
Among the issues that are likely to come up as the new standard
emerges are concerns over power and heat, though D’Ambrosia is
confident those concerns can be addressed.
The new IEEE specification will also need to find a way to work
with existing Optical Transport Networking (OTM) particularly at
“OC-768 is defined and deployed, whereas 100 G is an area where
the ITU is beginning to understand what we’re doing and working
with their own specifications to provide and ease of transition
between Ethernet layers and optical transport layers,” D’Ambrosia
Article courtesy of internetnews.com