[c-nsp] ONSs, DWDM SFPs, and the 3560/3750E

[Eric Van Tol]

> -----Original Message-----
> From: Justin Shore [mailto:justin at justinshore.com]
> Sent: Monday, April 07, 2008 9:12 AM
> To: Eric Van Tol
> Cc: 'Cisco-nsp'
> Subject: Re: [c-nsp] ONSs, DWDM SFPs, and the 3560/3750E
>
> Thanks for the reply, Eric.
>
> I should have given more detail in my post.  We're the ILEC in the
> area
> and own all the fiber (including what our upstream come in on to our
> data center).  While we own all the fiber, it's also a limited
> resource
> and definitely isn't free (though don't we all wish).  So in our case
> I
> have unfettered access to the dark fiber itself without interference
> from other equipment.  That definitely helps.  WDM is definitely
> doable
> in our scenario thanks to that.  I agree though that if this was
> through
> another provider we'd end up in a lengthy dark fiber lease to do the
> same thing.

Gotcha...makes more sense now.  :-)

> Yeah, I should have been more specific earlier.  Since we own the
> fiber
> we're not having to integrate this into something our upstreams are
> doing.  They are just one of many Ethernet connections that I need to
> transport between 2 points without over-subscription.  My bad.

So if I understand you correctly, you want to transport your transit connections from one location to another, along with an internal WAN link (or several).  If your only option is copper to some of your upstreams, I'd suggest a media converter that can take DWDM optics.  I believe MRV has some media converters that can do pluggable optics.  I can't find the info on their site, but I have a PDF that I can unicast to you if you'd like it.  I'd see this as being much cheaper than getting full-fledged switches whose only purpose is media conversion.

> I have a copy.  Unfortunately it's packed away in a moving box and
> won't
> be accessible until after I move next week.  The last time I cracked
> it
> open (almost 2 years ago) it was well over my head with my very
> limited
> ONS knowledge.  Perhaps now it will make more sense.  I've been told
> that the ONSs really aren't that hard to learn.  I'm sure they would
> make much more sense to me if I could see them in action.  Maybe I
> should pay a visit to Cisco's optical lab in Dallas.

Again, same boat.  It's my understanding as well that the ONS boxes are not hard to learn, especially with the CTC tool.  However, my experience with viewing the CTC (in Cisco's lab), as well as secondhand experience doing circuit grooms with one of our T1 providers, it can be slow and clunky.  Some circuits would take seconds to migrate and some would take minutes, with CTC crashing randomly in between grooms.  This was a few years ago, so take that with a grain of salt.  I've never been a fan of Java GUIs...

> > If I have your setup correct, then doing L2/L3 redundancy is your
> only option at this point.  Unless you can get dark fiber from your
> providers, WDM is not going to work.  I can say that moving to dark
> fiber can be costly at first, especially if your provider is a major
> player, but the long term benefits and cost savings are huge, since
> WDM offers almost limitless possibilities.
>
> Justin <-- *hangs head in digital shame*

Hope this helps,
evt