Re: 10GE CWDM

2008-09-07 Thread Bradley Urberg-Carlson, VISI
   On Mon, 01 Sep 2008 20:50:46 -0400
   Robert Boyle [EMAIL PROTECTED] wrote:
The only affordable CWDM 10G system I have seen although I haven't
   used it yet
is a single 10G band at 1310 or 1550 with 8 additional 2.5G bands
   around it.
   I've wondered if one could shoot with DWDM 10G optics into two channels
   of a CWDM mux.  For example, by connecting DWDM channel 359 (center
   1530.33 nm) and 334 (center 1550.12 nm) to the 1530/1550 filters of a
   CWDM mux with 20nm spacing (+/- 6.5nm pass band).  Might that support
   1x10gig + 3x1gig on a single strand, or 2x10G + 6x1G on a pair?  (and
   no, I haven't tried it).
   Bradley


Re: 10GE CWDM

2008-09-07 Thread Kevin Blackham
CWDM filter bandpass is wide to allow for drifting optics. Anything
within about 7nm of 1530/1550 should work fine. I've got some optics
near 34 and 59 on order to do exactly that in a bidir single fiber
arrangement. I'll report back my results.



On 9/7/08, Bradley Urberg-Carlson, VISI [EMAIL PROTECTED] wrote:
On Mon, 01 Sep 2008 20:50:46 -0400
Robert Boyle [EMAIL PROTECTED] wrote:
 The only affordable CWDM 10G system I have seen although I haven't
used it yet
 is a single 10G band at 1310 or 1550 with 8 additional 2.5G bands
around it.
I've wondered if one could shoot with DWDM 10G optics into two channels
of a CWDM mux.  For example, by connecting DWDM channel 359 (center
1530.33 nm) and 334 (center 1550.12 nm) to the 1530/1550 filters of a
CWDM mux with 20nm spacing (+/- 6.5nm pass band).  Might that support
1x10gig + 3x1gig on a single strand, or 2x10G + 6x1G on a pair?  (and
no, I haven't tried it).
Bradley


-- 
Sent from Gmail for mobile | mobile.google.com



RE: 10GE CWDM

2008-09-02 Thread Michael K. Smith - Adhost
Hello Alex:

 Depending how cheap and ghetto you want to get, there's also possibility
 of doing WDM on 1310/1300. I have custom-manufactured splitters filtering
 1307nm +-2nm - and any given LR XFP [*1] will be either within that band
 or outside [*2]. Test a bunch of them, split them into two groups, use on
 the tested wavelength. Bunch of friendsfamily are using this technology
 in production. This gives you an ability to do 20G with very cheap optics.
 
 
 [*1] Except ones with very temperature dependent wavelength - mark them as
 warms up to 1300 and use if you don't care that your links will take
 about 5 minutes to warm up and come up. :)
 
 [*2] Any LX4 Xenpak would be outside of the band as well, and you can
 use LX4 concurrently with LR.
 
 There are some more ghetto fabulous things you can do, described in
 http://www.nanog.org/mtg-0610/presenter-pdfs/pilosov.pdf ;)
 
 -alex
 
Do you have any issues with four wave mixing or other crosstalk issues or do 
you account for this in your channel plan?

Regards,

Mike


PGP.sig
Description: PGP signature


RE: 10GE CWDM

2008-09-01 Thread Robert Boyle

At 12:03 AM 8/31/2008, you wrote:
Currently it is my understanding the 10 Gbps signals are carried on 
4 x 2.5 Gbps signals that are compatible with existing CWDM and DWDM 
equipment. There are 40 Gbps DWDM systems and 10 Gbps lasers on 100 
Gbps and greater capacity systems. I agree with Alex's comments that 
to have 10 Gbps on a CWDM system is to have a CWDM system of at 
least 40 to 100 Gbps and that is very expensive today.


The only affordable CWDM 10G system I have seen although I haven't 
used it yet is a single 10G band at 1310 or 1550 with 8 additional 
2.5G bands around it. I haven't seen any 4 band 10G CWDM boxes with 
XFPs for less than $5000 yet, but I would expect them in the next 
year or two - I'm hoping anyway. I'm out of the country at the moment 
and access is a bit too slow to look it up easily now. If you need 
the manufacturer, let me know and I'll look it up when I return.


-Robert



Tellurian Networks - Global Hosting Solutions Since 1995
http://www.tellurian.com | 888-TELLURIAN | 973-300-9211
Well done is better than well said. - Benjamin Franklin




Re: 10GE CWDM

2008-08-30 Thread Nitzan Tzelniker
Hi,

Look here

http://www.btisystems.com/news/releases/Goldfield_Telecom.php

Nitzan

On Sat, Aug 30, 2008 at 21:54, Zed Usser [EMAIL PROTECTED] wrote:

 Hi!

 I seem to suffer from an acute lack of 10GE CWDM optics options. Is it just
 me or am I just looking in all the wrong places?

 You'd think that by now there would be an upgrade market from 1GE to 10GE.
 DWDM wavelenghts are not always available, but CWDM often are.

 - Zed







Re: 10GE CWDM

2008-08-30 Thread Alex Pilosov
On Sun, 31 Aug 2008, Nitzan Tzelniker wrote:

 Hi,
 
 Look here
 
 http://www.btisystems.com/news/releases/Goldfield_Telecom.php
These are XFP-based. Thus, not a solution to the problem above.

Answer: Nobody's making 10GE CWDM-wavelength lasers. Why? I don't have 
enough knowledge of optical equipment, but my understanding is that 
it is because:

a) Currently DWDM component suppliers already have a full load of 
orders and have problems scaling production - as evidenced by long 
lead times on any DWDM optics.

b) They wouldn't be much cheaper to produce than 
temperature-stabilized DWDM optics.

c) The demand is currently for amplifiable DWDM optics.

-alex




RE: 10GE CWDM

2008-08-30 Thread John Lee
Zed,

If you are looking for optical systems my fav pub is Lightwave at 
http://lw.pennnet.com/. They list DWDM and CWDM systems, lasers, optics, ROADM 
etc. If you have nanog archives go back at least six months to the thread on 
DWDM vs CWDM et al that I was one of the contributors to.

The last comment you make I do not understand since:

1. DWDM systems have many more lasers / wavelengths that are used and most 
metro and WAN providers can supply you a ITU wavelength at the normally obscene 
prices.

2. CWDM systems are usually 4, 8, 16, 24 that are also on ITU wavelengths like 
DWDM systems but with 50 - 100 nm or more spacing so the lasers and optics do 
not have to be so precise as the DWDM optics.

Currently it is my understanding the 10 Gbps signals are carried on 4 x 2.5 
Gbps signals that are compatible with existing CWDM and DWDM equipment. There 
are 40 Gbps DWDM systems and 10 Gbps lasers on 100 Gbps and greater capacity 
systems. I agree with Alex's comments that to have 10 Gbps on a CWDM system is 
to have a CWDM system of at least 40 to 100 Gbps and that is very expensive 
today.

John (ISDN) Lee

From Lightwafve:

Optelian adds CWDM XFP transceivers
AUGUST 19, 2008 -- Optelian (search for (search for Optelian)) has announced 
the availability of new LightGAIN 10-Gbit/sec CWDM XFP transceivers, which the 
company claims create a cost breakthrough in 10-Gbit/sec capacity growth by 
combining the low price points of CWDM with the inventory cost benefits of 
using MSA-compliant pluggable transceivers.
These new CWDM XFP transceivers are a cost-saving solution for 
fiber-constrained customers looking to grow their 10-Gbit/sec services [but] 
who don't need the full migration path provided by DWDM, explains Dave Dal 
Farra, senior Optelian product manager. And in higher growth networks, the low 
first cost and inventory savings can still be taken advantage of by adding up 
to 9 DWDM wavelengths into unused CWDM channels, utilizing Optelian's hybrid 
CWDM/DWDM multiplexers and 10-Gbit/sec tunable DWDM regenerators.

The new CWDM XFP transceivers are fully supported and backwards compatible in 
LightGAIN 6140, 5140, and 3060 systems, plugging into the existing RGN-10GXF 
10-Gbit/sec regenerator card. As part of LightGAIN, the flexibility of CWDM 
pluggable transceivers combines with Optelian's Quick-Turn Custom Passives so 
that custom 10-Gbit/sec CWDM configurations can be delivered as quickly as two 
weeks, claim company representatives.
Also useful for wavelength conversion, reach extension, and regeneration, the 
10-Gbit/sec CWDM XFP transceivers are now available for order. Key 
specifications include coverage from 1471 nm to 1611 nm, plus SONET and Gigabit 
Ethernet compliance for data rates with or without G.709 FEC.

From Alex's older e-mail:

On Fri, 25 Apr 2008, John Lee wrote:
 Subscribe to Lightwave (at no charge) and look at the back issues for 
 networks. Show up at Supercom or OFC or what is replacing them and get the 
 latest on ROADM, full channel tunable lasers and maintenance costs.

 What size of network do you want to grow to before replacing the optical link 
 equipment including ILAs?

 Most any org can cost justify a CWDM / CAN since you can add one fiber pair 
 at a time and one lambda per fiber pair.

 DWDM gear is much more expensive and is aimed at 20 to 40 lambdas per
 fiber for service providers while UDWDM and ULHWAN are aimed at trans
 oceanic links and are very very expensive.
DWDM gear is not expensive. Passive muxes cost little. Active
transceivers cost money but not very expensive at all.
Check out these two presentations (by yours truly et al):
http://www.nanog.org/mtg-0606/pdf/lightning-talks/4-pilosov.pdf
http://www.nanog.org/mtg-0610/presenter-pdfs/pilosov.pdf
-alex



From: Zed Usser [EMAIL PROTECTED]
Sent: Saturday, August 30, 2008 2:54 PM
To: [EMAIL PROTECTED]
Subject: 10GE CWDM

Hi!

I seem to suffer from an acute lack of 10GE CWDM optics options. Is it just me 
or am I just looking in all the wrong places?

You'd think that by now there would be an upgrade market from 1GE to 10GE. DWDM 
wavelenghts are not always available, but CWDM often are.

- Zed