At the open meeting of the 10X10 MSA on January 25th, the members and guests (50 in total) discussed requirements for a next generation form factor for the 10X10 that will be somewhere between the CXP and the CFP in size. The group discussed the goldilocks problem in this presentation [http://10x10msa.org/documents/Requirements_for_Next_Generation%2010x10%20Modules.pdf] where the CXP is too small and the CFP is too big. The new 10X10 form factor is designed to dissipate 6 Watts of power, so the CXP would be too hot while the CFP would be too cold. Goldilocks wants one new module that is juussttt right.
The talk of several new form factors for 100GbE did not sit well with many people in the room. End users for 10GbE understand the problem of alphabet soup all too well. Figure 1 shows the number of ingredients that are used to create 10GbE alphabet soup.
Figure 1: The First Serving of Alphabet Soup
Waiter: Do you want your 10GBASE-SR in an XFP, X2 or SFP+ form factor?
User: I prefer SFP+, the X2 gave me indigestion last year.
Waiter: Would you like that with a limiting interface or a linear interface?
User: Limiting, my network analyst told me to cut back on linear.
Waiter: Do you want that with OM3 fiber?
User: I’m on a high fiber diet of OM4.
Waiter: Sorry, we don’t serve that here.
The problem end users face with 10GbE alphabet soup is not funny. They have to buy, stock and track multiple replacement parts for various 10GbE switch products depending on which generation of 10GbE switch and blade they bought. This alphabet soup costs considerable time and money.
The Ethernet community is beginning to define several new form factors for 100GbE and more alphabet soup seems imminent as shown in Figure 2. The current list of second generation form factors includes CFP2, CFP4, QSFP2 and the next generation 10X10 module that we’ll call the CXP2 (two proposed names and solutions are CXP2 and XXP[http://10x10msa.org/documents/Proposed_Module_Concepts.pdf] and the CXP could even be used with exotic cooling techniques). The 10X10 MSA and the CFP MSA have no common members and neither MSA is expected to back down from defining these new form factors.
Figure 2: More Alphabet Soup for you?
The CXP2 already has an electrical interface defined and the optical interface will be released soon. The CXP2 is based on the CPPI (unretimed) electrical interface defined in 802.3ba. The CFP2 and CFP4 will probably use the CAUI-4 and CPPI-4 (not official yet) electrical interface that are expected to begin being defined in the IEEE in July, 2011 in a new study group. The new IEEE study group will also investigate the need for new optical interfaces such as 100GBASE-SR4, and 100GBASE-FR4 ( a single-mode variant for 2km?). The single-mode optical interfaces (100GBASE-LR4 for 10km and 100GBASE-ER4 for 40km) were defined in 802.3ba with 100GBASE-SR10. The industry will need to contribute considerable effort to get these new technologies defined and deployed.
Because of the mature nature of the 10Gbps technology of the 10X10 MSA, the cost of the 10X10 technology will remain lower cost than 100GBASE-LR4 technologies in the CFP, CFP2 or CFP4 form factors for several years. The integrated photonics technology used in the 10X10 will keep the cost below the cost of the discrete components used the LR4 solutions until they also use integrated photonics. The CFP2 and CFP4 will be based on new 4x25Gbps signaling that will take years to bring to market. The alphabet soup from the 10X10 is limited to the CFP and CXP2 while the 100GBASE-LR4 soup will have CFP, CFP2, CFP4 and QSFP2 floating around for a few more years.
If you want to join the discussion on next generation 100GbE Form Factors, go to:
1) http://10x10msa.org/documents.htm regarding presentations on the next generation form factor and join the group by emailing info@10x10msa.org. To join the public reflector to see announcements about upcoming meetings to discuss the higher density form factor, go to http://groups.google.com/group/10x10g and click on the "Sign in and apply for membership" button.
2) http://www.cfp-msa.org/Documents/CFP_MSA_OpGuidelines_Issue1-1.pdf to see how you can become a sponsor member to the CFP MSA. They don’t seem to have any sponsor members or public information about their next generation form factors.
3) http://tech.groups.yahoo.com/group/NG100GbE/ to discuss the next generation PMDs and electrical interfaces that will be defined in IEEE.
4) The QSFP2 is being designed for 100GbE applications with 4 lanes of 25Gbps by the SFF Committee (www.sffcommittee.org) and is not designed to be backward compatible with the QSFP so that it can dissipate more power and not get too hot.
Enjoy your soup,
The 10X10 MSA
PS. For a thorough understanding of Ethernet alphabet soup (nomenclature like 10GBASE-LX4 or 40GBASE-FR), read this white paper titled the Evolution of Ethernet Nomenclature: http://www.brocade.com/downloads/documents/technical_briefs/Ethernet_Nomenclature_GA-TB.pdf.
PSS. See how Brocade and Alcatel-Lucent plan to support the 10X10 in this NANOG presentation:
