Opportunities for CXP AOCs and Transceivers

For those of you that believe that 100-Gigabit Ethernet is just around the corner, I have a bridge I want to sell you. But seriously, we haven’t even seen the height of 10-Gigabit Ethernet adoption yet, and there are some equipment companies saying they will sell 100’s-of-thousands of CXP 100GBASE-SR ports in 2011. Are you kidding? What is the application and where is the need?

First, 10GE has taken more than eight years to get to a million ports – we believe it will take 40G and 100G even longer. Second, even for clustering applications, which could potentially drive demand faster, 100GE port-adoption won’t be that quick. Ethernet architecture is different than the InfiniBand (IB) one – the density of an IB director-type switch provides over a Terabit per second, whereas the newly released 40GE ones are around 250G (due to both slower data rate and fewer ports). IB is also based on a CLOS architecture where you have equal bandwidth everywhere, while Ethernet is more often used in an aggregated network so ends up having a lot less higher-speed ports than lower speed ones. This is further supported by clustering applications that use ToR switches that are currently Gigabit connections to the servers with 10G uplinks to the network core. These will be upgraded to 10G downlinks and 40G uplinks first and this won’t happen quickly.

While several IP router manufacturers claim to have the need for 100’s of thousands of 100GBASE-SR CXP ports in 2011, I have found no evidence of this. Who are their customers? In fact, even those companies that could use 100G ports today, i.e. Google, Facebook , IXCs, etc., would need six months to a year to evaluate IP router products before they would deploy them. Since these devices do not yet exist, the reality is that the market will really not begin to materialize until at least 2012. Right now, the majority of router connections are still Gigabit Ethernet or OC-48 (2.5G) or below with OC-192 (10G) or 10GE being implemented on an as-needed basis. Until routers transition through 10G, then probably 40G, 100G installations will be few and far between.

But, there is a market for CXP AOCs today – InfiniBand. This is becoming a volume market now and will continue to be the best opportunity for CXP AOCs for at least the next few years and probably over the lifetime of the CXP products. In fact, we expect the volume of InfiniBand CXP AOCs to be at about six million by 2015. By comparison, the total volume of Ethernet CXP AOCs is expected to be less than 100-thousand. While 100G Ethernet clustering applications will initially use CXP AOCs, customers in these markets prefer to use pluggable modules mainly because they are used to structured cabling solutions and like their flexibility and ease of use, so AOCs will quickly give way to pluggable modules as they are developed. 100GE CXP ports may eventually eclipse InfiniBand once it permeates most data center distribution and core networks, but this will take longer than any of these equipment vendors anticipate I think.

Common Electrical Interface for 25/28G – a Possibility or a Pipe-Dream?

Yesterday, I sat through a workshop hosted by the Optical Interconnecting Forum (OIF) on its “Common Electrical Interface (CEI) project for 28G Very Short Reach (VSR).” What quickly became clear to me was that I was in a room of VERY optimistic engineers.

I sat through presentations that were characterized as “Needs of the Industry,” which consisted of content from the leaders of IEEE 802.3ba (40/100G Ethernet), T11.2 (Fibre Channel) and InfiniBand standards groups. Yet all of these representatives made sure they carefully stated that what they were presenting was their own opinions and not that of their standards groups, which I found odd since most of what they showed was directly from the standards. Legalities I guess. I also noticed that they never really sited any kind of independent market research or analysis of what the “needs of the industry” were. For instance, one speaker said that InfiniBand has a need for 26AWG, 3-meter copper cable assemblies for 4x25G operation in order to keep the cost down within a cabinet. Yet, he did not present any data or even mention what customers are asking for this. Maybe this exists, but to me unless it is presented, the case for it is weak. I do have evidence directly from some clustering folks that they are moving away from copper in favor of fiber for many reasons – lower power consumption, weight of cabling, higher density, and room in cabinets, pathways and spaces.

Today, data center managers are really still just starting to realize the benefits of deploying 10G, which has yet to reach its market potential. I understand that standards groups must work on future data rates ahead of broad market demands, but this seems extremely premature. None of the current implementations for 40/100G that use 10G electrical signaling have even been deployed yet (except for maybe a few InfiniBand ones). And, from what I understand from at least one chip manufacturer who sells a lot of 10G repeaters to OEMs for their backplanes, it is difficult enough to push 10G across a backplane or PCB. Why wouldn’t the backplane and PCB experts solve this issue that is here today before they move onto trying to solve a “problem” that doesn’t even exist yet?

Maybe they need to revisit optical backplanes for 25G? It seems to me that 25G really won't be needed any time soon and that their time would be better spent on developing something that would appear to have relevancy beyond 25G. To me, designing some exotic DSP chip that would allow 25G signals to be transmitted over four-to-12 inches of PCB and maybe 3m of copper cable for one generation of equipment may not be very productive. Maybe this is simpler than I anticipate, but then again, there was a similar but a little more complicated problem with 10GBASE-T and look how that turned out...