[c-nsp] Cheap 10G between 7600 and Procurve 5406zl

[Lincoln Dale]

On 15/03/2010, at 7:57 AM, <Christopher.Marget at usc-bt.com> <Christopher.Marget at usc-bt.com> wrote:

>>>>> 
>> twinax support claims I've seen to date.  I'm hopeful that vendors will
>> come to their senses on pluggables, at least for twinax cabling.
>> 
>> HP are currently locking in to HP transceivers.  email promise or not,
>> thats the current behaviour.
> 
> Can you shed any light on Cisco's stance on the matter?  From the Cisco side we have:

SFP+ is one of the newest transceiver formats and has a lot more of the 'stuff' that used to be inside the transceiver on the switch PCB itself.  one of the things that has been moved is a component called the EDC (electronic dispersion compensation).  different transceiver types have different requirements as far as EDC parameters and this has been one case where it shows that not all transceivers are created equal.

with non-optimal or incorrect EDC values you may still get "link up" but you may have such an excessive error-rate that its practically unusable.  or you may get cases where link comes up but randomly drops out.  or doesn't drop out when the link partner goes away.

point being here is that while its a commonly held belief that "all transceivers are created equal" we have seen this to not be the case with SFP+ -- probably because its the "newest" transceiver format for 10G.


in terms of N7K the currently-shipping 32 port 10 Gbps Ethernet Module w/ M1 forwarding engine (N7K-M132XP-12) only supports SR and LR optics at this point in time.  no LRM or passive CX1 1m/3m/5m.
will it support more optics in future?  yes.  talk to your cisco account team and i'm sure they can provide you with details.

in terms of N5K the current shipping hardware supports SR, LR and passive CX1 1m/3m/5m.  it also enables support for some specific 3rd party passive CX1 that we have validated and have appropriate EDC values for.  this includes NetApp, EMC and HP branded passive CX1 transceivers.
note that while Cisco supports HP passive CX1 transceivers the same does not hold true in reverse.
just like how N7K will add support for more transceiver choices so too will N5K.  again, your cisco account team should be able to provide details.

> 
> No LRM SFP+ optics.

not yet.  but never say never!


cheers,

lincoln.