[c-nsp] is a DWDM SFP a DWDM SFP?

[Nick Hilliard]

On 25/11/2009 16:17, Scott McGrath wrote:
> I can see their point especially in SP networks and to keep the
> counterfeit optics at bay but we have the same problem CSCO does not
> make the optics we need in many cases and in the LAN environment it
> makes even less sense, As unless a optic is egregiously bad it generally
> will not matter but a device down will...
>
> Don't SUPPORT third party optics but give us the option to use them
> without resorting to hacks. What's even worse is that most of CSCO's
> optics are indeed Finisar optics with different firrmware.

Different serial numbers, whatever about the firmware.

This isn't "what's worse".  Cisco simply doesn't manufacture optical 
transceivers.  Like all other major switch/router manufacturers, they spec 
from a small number of third party manufacturers (finisar, opnext, etc), 
just like they do with flash chips and DRAM and so on.  It's just 
economics: it's cheaper and simpler for them to buy rather than build.

Yes, there are trash quality optics out there, no doubt about it.  Due to 
massive vendor markups, many of them are labelled with vendor labels and 
sold as genuine vendor products.  Again, this comes entirely down to 
economics: so long as you make it worth someone's while to build a 
knock-off, they will do it.  And that will damage everyone, including the 
vendors

"service unsupported-transceiver" is not a hack:  it's the deconfiguration 
of a software misfeature whose sole intent is to cripple your equipment's 
functionality.   At the same time, it provides an clear warning that if you 
use third party products in your kit, Cisco will not support them.  This is 
not unreasonable and it's a much better and more customer focussed approach 
than some vendors who will simply refuse point-blank to accept third party 
transceivers.  I guess there will always be customers who are gullible 
enough to accept this sort of b/s vendor gouging.

Unfortunately, Cisco (and several other vendors) have chosen not to fully 
de-crippling third party transceivers, so that even if you use this 
command, you still lose DOM. I have heard some people claim that they've 
been told by their vendors that this was to ensure that DOM measurements 
were accurate.  Charitably, this is a weak argument, particular when you 
take into account that some of the DOM readings on some older (but genuine) 
transceivers bear no relation to reality, and also that Cisco resell lots 
of transceivers which won't work in other Cisco kit - unless you use 
"service unsupported-transceiver" or equivalent.

No, it's about money and margins, pure and simple.  Most vendors jam on a 
margin of between 5x and 15x on their transceivers, and that's the sort of 
margin that's very easy to get addicted to.

Nick