Hi Jonathon, I probably will not be answering your question completely. But perhaps just a bit of input for some further searching?
My understanding is that the first generation 100G PHY standard was IEEE 802.3ba-2010 and that used 10 lanes at 10G line rates. However, I believe the only standard that used a SFP based module was the copper 100GBASE-CR10 using a QSFP+ transceiver. The rest were the CX style transceiver modules. And so most 100G switches using QSFP28 transceivers this would not be a standard implementation they would support because the underlying line rate is the 28Gbps. Typically what I see for example is that each port of a 32-port 100G QSFP28 switch can be configured as 32 40G ports that then is based on the SFP+ standard for 10G and can do 128 10G ports. So using QSFP28/SFP+ where the underlying line rate in the PHY is 28Gbps may not be feasible (however I am not an authority here and cannot say it doesn’t exist). But again, there is an old standard that does use 10x10 and you may be able to follow that route if interested? But it is old technology and probably hard to come by? Best, Mitch > On Nov 30, 2022, at 9:09 AM, 'Jonathan Weintroub' via > casper@lists.berkeley.edu <casper@lists.berkeley.edu> wrote: > > Hi CASPERites, > > I believe that 40 Gbps Ethernet interoperates rather transparently with 10 > Gbps. Because the 40 Gbps is arranged as four x 10 G lanes, so its possibly > to break a 40 QSFP port into four 10 SFP+ with a suitable breakout cable. Or > with proper packet addressing via a network switch with 40 and 10 ports. > > Likewise 100 Gbps interoperates with 50/25 easily. And 400 with 200 and 200, > and so on. > > The question arose in a meeting today whether it’s a simple matter to > transform a 100 Gbps Ethernet stream into 10 Gbps streams, 10 of them or > whatever? There are various switches on the market with both 100 and 10 Gbps > ports, but not clear whether these re distinct networks, or whether they > transparently interoperate. > > Can someone offer input as to whether transforming 100 Gbps QSFP28 into > multiple 10 Gbps SFP+ links is easily accomplished in a suitable switch? Or > a complicated endeavor? > > Hope this is clear. Thanks, > > Jonathan > > > > -- > You received this message because you are subscribed to the Google Groups > "casper@lists.berkeley.edu" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to casper+unsubscr...@lists.berkeley.edu. > To view this discussion on the web visit > https://groups.google.com/a/lists.berkeley.edu/d/msgid/casper/1C6A1476-CBFD-4498-9DE5-2DE747741556%40cfa.harvard.edu. -- You received this message because you are subscribed to the Google Groups "casper@lists.berkeley.edu" group. To unsubscribe from this group and stop receiving emails from it, send an email to casper+unsubscr...@lists.berkeley.edu. To view this discussion on the web visit https://groups.google.com/a/lists.berkeley.edu/d/msgid/casper/0DE96746-94B2-485E-8F76-445EE24A5136%40byu.edu.
