> Can one use the zarlink (or something like it) on the ROACH end, and > connect the fiber to an SFP+ module in the computer or switch? It seems > like someone ought to make such a beast, considering there are a lot of > cx-4 ports in the field that need to be connected to new CX-4 - only
Er, make that SFP+ only > switches and NICs. > > This is, I'm afraid, the downside to throwing in your lot with commercial > products. You're at the mercy of the markets. > > John > > >> I am avoiding Myricom for the reasons Rick mentioned. It took a long >> time >> for me to get the sales/technical person to even understand that I >> wanted >> to >> go from CX4 to fiber. >> >> But Chelsio, as several have mentioned on this list, provides the power >> necessary for transceivers to work. They also have offloading cards >> (which >> I >> believe is what you're describing) - or at least they did until the >> discontinued their CX4 line. Not sure what the new Chelsio product line >> will >> look like and I am somewhat dubious that they will stay on the 4-6 week >> timeframe. Every vendor that I and a collaborator have called are out of >> Chelsio CX4 stock. >> >> Intel makes 10gbe cards, but the list archives are ambiguous as to >> whether >> they power the transceivers in the Zarlink cables. >> >> My primary concern is that if companies already see fit to discontinue >> CX4 >> products, then (a) it is hard to connect to the ROACH now and (b) will >> be >> nearly impossible when something breaks in 6 years. >> >> How far along are the GMRT folks? >> >> Tom >> >> On Fri, Jan 28, 2011 at 6:06 PM, rick raffanti <[email protected]> >> wrote: >> >>> The Myricom people told me they don't make NICs with active ports- ie, >>> aux >>> power for the fiber translator. That's why we bought the Chelsio. >>> Anton is >>> getting 6Gb/s throughput with the Chelsio- we haven't tried to push it >>> further. I wasn't aware of the UDP packet handling stuff, though. >>> >>> Rick >>> >>> >>> On 1/28/2011 5:53 PM, Dan Werthimer wrote: >>> >>> >>> hi tom, >>> >>> one more note: >>> >>> if you use fiber optic CX4 cables, >>> please see the warning at >>> >>> http://casper.berkeley.edu/wiki/Recommended_10_GbE_Hardware >>> >>> not all NIC boards have built in power to support >>> fiber optic cables. check with myricom. >>> the ibob/bee2/roach boards have built in power. >>> >>> dan >>> >>> >>> On 1/28/2011 2:41 PM, Tom Downes wrote: >>> >>> So Chelsio has end-of-lifed their CX4 line. They say "4-6 weeks" until >>> new >>> cards come out as part of a new product line, but their sales contact >>> said >>> this reflected a larger recognition that CX4 is not how the industry is >>> going. >>> >>> My thought is that I should be buying an SFP+ card and figuring out a >>> way >>> to convert to CX4, e.g. SFP+->optical, optical->CX4. Our cable lengths >>> that >>> we will (eventually) need are all greater than 15m, so outside of the >>> CX4 >>> spec, much less what the ROACH boards are apparently cable of driving. >>> >>> Is such a transceiver scheme plausible? I am having trouble finding >>> the >>> appropriate parts. >>> >>> Tom >>> >>> On Mon, Aug 9, 2010 at 8:11 AM, Matt Dexter <[email protected]> >>> wrote: >>> >>>> Yes - when pricing switches, or any sort of (sub-)system, a full >>>> BOM must be used to make a meaningful comparison. >>>> >>>> Matt >>>> >>>> >>>> On Mon, 9 Aug 2010, John Ford wrote: >>>> >>>> And don't forget that the switches that are XFP and SFP+ sometimes >>>>> (usually?) don't include the optics for each port in the switch >>>>> price. >>>>> >>>>> With CX4, all you need is a cable, if you're within a few meters. >>>>> >>>>> Yes - that list is years old. >>>>>> Those Fujitsu and HP switches have been tested with the CASPER >>>>>> hardware >>>>>> and found to work as advertised. >>>>>> >>>>>> There are lots of new products available. More announced >>>>>> all the time. We are in contact with a number of vendors in >>>>>> hopes of getting demo units to try in house with the CASPER >>>>>> hardware before listing them as recommended for use. >>>>>> Our tests will include running at full line rates all ports >>>>>> continuously >>>>>> as that's what our intended applications require. >>>>>> >>>>>> Less demanding applications will have many more, and >>>>>> cheaper, options for suitable switch vendor and model. >>>>>> >>>>>> I have no prediction for when I will be able to add more switch >>>>>> models will to that list. >>>>>> >>>>>> Matt >>>>>> >>>>>> On Thu, 5 Aug 2010, Andrew Lutomirski wrote: >>>>>> >>>>>> On Thu, Aug 5, 2010 at 3:21 PM, Matt Dexter <[email protected]> >>>>>>> wrote: >>>>>>> >>>>>>>> Hi Tom, >>>>>>>> >>>>>>>> were you aware of these ? >>>>>>>> http://casper.berkeley.edu/wiki/Recommended_10_GbE_Hardware >>>>>>>> >>>>>>> >>>>>>> Sadly the list is out of date: some of the switches are no longer >>>>>>> in >>>>>>> production. The XG700, for example, is great and cheap but you >>>>>>> can't >>>>>>> buy one without great difficulty. >>>>>>> >>>>>>> I'm not sure that manufacturers really care about CX4 anymore now >>>>>>> that >>>>>>> SFP+ parts are available. >>>>>>> >>>>>>> --Andy >>>>>>> >>>>>>> http://casper.berkeley.edu/wiki/Equipment_Cables >>>>>>>> Matt Dexter >>>>>>>> >>>>>>>> On Thu, 5 Aug 2010, Tom Downes wrote: >>>>>>>> >>>>>>>> Casper-folks: >>>>>>>>> >>>>>>>>> Hoping to short-circuit a fair amount of research here in the >>>>>>>>> hope >>>>>>>>> that someone has had to do this already. I'll soon be looking to >>>>>>>>> connect 10-20 ROACH boards by 10 gbe to a data acquisition >>>>>>>>> computer(s). >>>>>>>>> >>>>>>>>> It seems like the smartest way of doing that is getting a 16-port >>>>>>>>> switch or potentially two 8-port switches. But the 10 Gbe port on >>>>>>>>> the >>>>>>>>> ROACH seems to be CX4 which I take to be a less popular connector >>>>>>>>> variety. >>>>>>>>> >>>>>>>>> What kind of switches have ROACH users out there used to connect >>>>>>>>> up a >>>>>>>>> bunch of boards? Are there switches out there to convert CX4 to >>>>>>>>> something with a reach longer than the 15m Wikipedia quotes as >>>>>>>>> the >>>>>>>>> limit of CX4. 15m is very borderline for our needs. >>>>>>>>> >>>>>>>>> The prices seem to vary widely. We do not need network admin >>>>>>>>> tools >>>>>>>>> or >>>>>>>>> anything fancy. In fact our data rates could probably go over >>>>>>>>> 10Mb >>>>>>>>> cabling, but the 10Gbe interface of the ROACH is more convenient >>>>>>>>> from >>>>>>>>> the firmware perspective. This is more of a multiplexer than a >>>>>>>>> switch. >>>>>>>>> >>>>>>>>> Tom >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>>> >>>>>>> >>>>>> >>>>> >>>>> >>>>> >>>> >>> >>> >> > > >
