[c-nsp] ASR9k CWDM Optics

[Nick Hilliard]

On 15/10/2011 18:03, Phil Mayers wrote:
> I'd be interested to hear which models of WDM transponders people have used
> successfully

Lots.  I have used Transmode and MRV and very much like both of them.
Other people say lots of good things about Adva, Ciena, Cisco, Ekinops,
Huawei, etc.

> I'm particularly curious about "features" like power
> monitoring and dual PSU.

Generally speaking, WDM kit tends to be very reliable.  You plug it in and
it works tirelessly until the day it's decommissioned.  They all have
redundant power feed systems and almost all of them support -48VDC.  Some
are better for monitoring than others.  Almost all of them support
genuinely hitless management card upgrades, which is really nice.

I like them.  They abstract out your 10G wave delivery platform from your
particular choice of L2/L3 kit at a particular time, which can be very
strategically beneficial.  Particularly from a cost point of view,
actually.  What happens if you switch from one L2/L3 kit type to another,
and there is a transceiver incompatibility? E.g. XENPAK->XFP for
7600->ASR9k migration.  Or a vendor migration and you find that your
transceivers from the old kit either don't work on the new kit or else that
they are crippled due to crappy vendor policies about DOM, etc.  They also
open up the possibility of using SFP+ blades for long-haul.  While there is
DWDM SFP+ available these days, it's still debatable as to whether it is or
will ever be a good long-haul wave delivery transceiver format.  However
with WDM transmission systems, you simply don't need to worry about that.

Nick