To pull this back to time nuts territory, this brings up the idea of simply using traditional ethernet infrastructure, be it 100M/1G/10G/whatever at the PHY layer to achieve distribution of 1pps. The infrastructure is easily enough interfaced to, even a simple microprocessor can do it, using switches allows for distribution with known characteristics. Not sure that you'd need to climb up even into Layer 2, but if you do, that would allow for identification of the sources by MAC address. You's still have to worry about collisions I suppose. There are other networking technologies that could also be used with less impact and better characteristics, with infiniband (lossless, low latency) coming immediately to mind.
On Thu, Mar 21, 2019 at 11:03 AM Julien Goodwin <time-n...@studio442.com.au> wrote: > > The lock in is almost entirely vendor profiteering, optical monitoring & > wavelength switching are standards (where implemented), but plenty of > vendors use (almost always trivially bypassable) lock-in to sell SFPs > they rebrand from the same OEMs at up to 100x markup. > > The folk in the big telcos (or in my case, big content providers) who > run the global backbones have plenty of stories. > As one of the guys who has to make these decisions for a big company, I have to pipe up in our defense. It has very little to do with profiteering, though it is easily seen as such. In reality, there are a number of vendors of transceivers out there (or other similar parts) ranging from excellent to really horrible. The 'lock-in' is to restrict the pool to those that have been qualified and tested. This vastly reduces support and service hassles on both ends of the phone call. The incremental revenue on a transceiver of, in one case I can document, of about $600, even when multiplied by the number required for a full system, isn't even in the decimal points of the total cost of the system, which can easily exceed $3-4M. Bob _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.