Re: Cheap switch with a couple 100G

[Fredrik Korsbäck <hugge () nordu net>]

On 2018-11-25 21:16, Mike Hammett wrote:
> No, not new. No need to buy new switches when there are so many used available (except for now needing 100G). Switches
> have an extremely long life. I have a client that has 15 year old Foundry switches that just work, though we're 
> looking
> to replace them to get some 10G ports.
>
> The pricing was part of my point. For years everyone says just skip 40G and go to 100G. The price difference isn't 
> that
> much....  but it is.
>
> "Everyone just skipped 40G and went for 100G." Then why is there such an availability of 40G switches? Obviously they
> weren't skipped, but purchased and then later replaced.
>
> Looks like $280 for an LR4 40G and $800 for an LR4 100G. Still a premium for 100G over 40G.
>
>
>
> -----
> Mike Hammett
> Intelligent Computing Solutions
> http://www.ics-il.com

Whole bunch of Apples and Oranges mixed here.

* 40G in the ISP/Telco world is more or less non-existant. There was never a good uptake on any products aimed towards
ISP/Telco that did 40G cost-effectively. This is partly because 40G was/is never a thing in the DWDM-world either. There
was some STM256 built and some OTU3 built aswell but not nearly in the same density as 10G was and 100G is built today,
it had a weird timing with being fairly close to 100G and abit to distant to cost-effective 10G so it never had any good
usecase. So if you buy services from a Telco, its very likely that 40G handoff is the least preffered option for them.
Or most likely not a option at all (like from every company ive been involved with)

* You compare market-economics with what new stuff cost vs used stuff on ebay/liquidators cost. Thats not a sane way of
doing math, the reason why old 10/40 nexus and arista etc is plentiful on ebay is because people switched it out to
something newer, faster. There isn't currently anything faster on the market then 100G-switches so naturally there isn't
much of that available used. Now that at least some product-families (spine switches) getting 400G with the new
TH3-switches we can assume that there is a decent amount of older 100G spines getting decommisioned, and hence getting
available in the second hand market (maybe even late next year). However there has been _a lot_ of datacenters being
lifted from 10G/40G to 25/50/100G architecture the last year, so it makes sense that the predecessor is on ebay.

If you are to buy *new* stuff id say that going for 100G of 40G architecture makes sense in almost every aspect,
regardless of what products and usecase you have. If you rely on second-hand, then sure, 40G might be a decent choice.
However i would cry if id have to buy 40G optics today since i know they be binned in a year anyway. (4x10G PIR is still
usable optics in 100G land though).


-- 
hugge