[c-nsp] Cisco and third party transceivers

[Jason Lixfeld]

On 2011-09-27, at 4:17 PM, Martin T wrote:

> Hello,
> there are providers like Flexoptix(http://www.flexoptix.net) who are
> able to flash SFP EEPROM memory with different vendor data, probably
> set custom serial numbers etc. However, why is such service needed at
> nowadays for Cisco equipment? Every router/switch I have seen supports
> the "service unsupported-transceiver"(should turn of checking the
> "Cisco Quality ID") and "no errdisable detect cause gbic-invalid"
> commands and thus doesn't check the ID code in EEPROM..

Just because a third party optic is recognized (by way of EEPROM flash or service unsupported-transceiver) by your gear, it doesn't automatically mean that it will perform on par with a genuine optic.

When we started our 10GE foray last year, we had no end of problems with third party optics.  It wasn't until we ran the optics through RFC2544 tests back to back and in our gear that we were able to differentiate the good ones from the bad ones.  We do this routinely for our 10G and 1G (duplex, Bidi and T) whenever we get a batch of SFPs that we don't recognize.

If you don't fully test your optics, you will be plagued with small little niggling issues that can't really be identified with any degree of certainty.  I've found that as the bit rates go up, it's more imperative than ever to test absolutely everything.  The smallest little defect can manifest itself in so many different ways.

The investment in RF2544 testers and OTDR testers has paid itself back in full, repeatedly.

> Last but not least, does SmartNet require you to use Cisco branded
> transceivers? I have heard that this is true only in case the fault or
> unexpected behaviour is related to transceiver..

Use whatever optic you want, but if you're going to open a TAC case, they'll ask you to put a Cisco optic in before they do something like RMA a line card.