I just turned 30 and still saw a fair amount of 10BASE2 (with BNCs) when I was working at the computer help desk in college. It's not that old.
Yes, it's extremely puzzling that there isn't an off-the-shelf solution for this that everyone knows about. Tom On Sat, Jan 29, 2011 at 10:17 AM, John Ford <[email protected]> wrote: > > I'm talking with the engineers at Chelsio about just such a beast and > > expect > > a call back on Monday. I imagine I'll go with CX4 on both ends and > Zarlink > > for now, but it seems like something the ROACH community needs to think > > about - sound like GMRT is doing something like this. > > > > Every time I've spoken with an engineer at Chelsio or Myricom about > > CX4-SFP+ > > (probably with fiber between), the initial reaction is something like > Bugs > > Bunny saying "Hansel". It's as if it were something they would never have > > considered doing in a million years. I think the conventional wisdom is > > not > > just that these transceivers can impede speed, but can also impede the > > ability of the link to remain up at all. > > I got the same reaction. It's puzzling. > > I guess they weren't around for the original "waterhose" ethernet -> > 10base2 -> 10baseT -> 10baseFX -> 100baseT -> 1000baseT progression. > > In other words, why the heck would you *not* have a heterogenous bunch of > networks, transcievers, and media once the first working products were out > for a few years? > > John > > > > > Tom > > > > On Sat, Jan 29, 2011 at 9:57 AM, John Ford <[email protected]> wrote: > > > >> 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 > >> 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 > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>>> > >> >>>>>>> > >> >>>>>>> > >> >>>>>> > >> >>>>> > >> >>>> > >> >>>> > >> >>>> > >> >>> > >> >> > >> >> > >> > > >> > >> > >> > > > > >
