[59246] in North American Network Operators' Group
RE: Advice/Experience with small sized DDWM gear
daemon@ATHENA.MIT.EDU (Deepak Jain)
Fri Jun 20 14:57:18 2003
Reply-To: <deepak@ai.net>
From: "Deepak Jain" <deepak@ai.net>
To: "Arman" <arman@unitedlayer.com>, <nanog@merit.edu>
Date: Fri, 20 Jun 2003 14:56:41 -0400
In-Reply-To: <3EF2B8C8.398848D7@unitedlayer.com>
Errors-To: owner-nanog-outgoing@merit.edu
> Nanogers,
>
> We are looking for advice/experience from folks who has used small 6-8
> Wavelength DDWM.
>
> Also what are the pros and cons of CDWM and DDWM?
>
> Application; 5 Mile Dark Fiber between two carrier neutral hotels in SF.
>
> All help is appreciated and results will be shared if requested.
>
Arman,
I think the biggest difference between small DWDM and CWDM is how much
growth room you need.
If you need 8 wavelengths (possibly 16 is still called CWDM but I doubt it)
you can stay on the CWDM side. The lasers and the gear is generally cheaper.
With DWDM gear everything seems to be more expensive, but you get a lot
more control as the electronics governing the chassis' tend to be much more
advanced. On a short run like that, many advanced features like all-optical
amplification and such are not necessary. I am not aware of any all-optical
CWDM amplifiers yet. (for example).
If you are planning more than just 1 DF run, you could buy the less
expensive solution and just swap it out when you need something more and use
the CWDM solution somewhere else.
If you have decent/modern fiber, you should be able to comfortable signal
8 waves x 1G or 8 x 2.5G (full duplex). Some DWDM gear will let you double
that on just 8 colors by going full duplex on each fiber (each thread).
So its a question of how much BW you need and how much you want to pay
for right now.
(If I am wrong, someone please correct me).
Hope this helps, let me know what you decide.
Deepak Jain
AiNET
