Why is the 10x10 Standard Needed?

The 10x10 optical standard is fulfilling the need for intermediate link distances of 100GbE within the data center.  The IEEE has defined a number of links for 40GbE and 100GbE as shown in Table 1, but the difference between 100 meter links and 10,000 meter links is too big when you consider that a 100GBASE-LR4 solution can be over 10 times more expensive than a 100GBASE-SR10 link.  The 10x10 solution typically costs less than half the price of the 100GBASE-LR4 solution and bridges the gap between cost effective 100 meter links and very expensive 10km links outside of the data center.  The 10x10 modules also consumes about 12 Watts less power on a link than 100GBASE-LR4.  The 2km distance of the 10x10 offers a cost effective and efficient solution for large data centers that need to go farther than 100 meters but less than 10km

Table 1: 40 and 100GbE Variants

	Backplane	CR	SR	FR	10x10	LR	ER
40GbE	1m	7m	100m	2km	N/A	10km	N/A
100GbE	Being defined	7m	100m	N/A	2 km	10km	40km

The 802.3ba project (http://www.ieee802.org/3/ba/index.html) that defined 40GbE and 100GbE limited the scope of the project so that the project could be completed in about 4 years.  The Higher Speed Study Group (HSSG) started in July 2006 and the 40 and 100GbE standard was finished in June 2010.  To not delay the standard, they only defined 100 meter, 10 km and 40 km fiber optic solutions.  If more distances were added between 100 meters and 10km, then the standard would have taken longer and the Ethernet community was hesitant to define other links and delay the release of the standard.

The first follow on project to 802.3ba related to 40 and 100GbE was the 802.3bg task force that defined a 2km link as 40GBASE-FR (http://www.ieee802.org/3/bg/index.html).  In November 2010 at the hotel with the IEEE meetings, the Next Gen 100GbE Optical PMD Discussions had a straw poll to start a Call For Interest (CFI) specifically for a 2 km solution that could support the 10x10 solution. The motion was voted down by a fact of 4 (5 yes to 21 no).   Members of the IEEE were not very interested in defining a 100GbE link at 2km in a separate standard, so the 10x10 MSA was created to fill that need.  It was clear to members of the 10x10 MSA that several man-years of effort and a couple calendar years of time would be needed to create the IEEE standard for 100GbE at 2 km.  Instead of going through this painful process, the 10x10 MSA was formed. 

The 10x10 solutions is designed to meet the needs of users who need to go beyond 100 meters but less than 2 km.  Many data centers have link requirements beyond 100 meters, but don’t need to go much more than a few hundred meters.  The 10km solutions for these applications is overkill because the 10x10 solution can meet the link requirements at less than half the cost of 100GBASE-LR4 and about 70% of the power (14W for 10x10 vs 20W for 100GBASE-LR4).  Since the 10x10 is CFP compatible and can fit in the same port as 100GBASE-LR4, customers will see the benefits of the 10x10 over 100GBASE-LR4 for link distances over 100 meters but under 2 km.