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
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. 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
On Mon, 1 Sep 2008, Robert Boyle wrote: the "tested" wavelength. Bunch of friends&family 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
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 friends&family 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
On Mon, 01 Sep 2008 20:50:46 -0400 Robert Boyle <robert@tellurian.com> 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
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 <buc@visi.com> wrote:
On Mon, 01 Sep 2008 20:50:46 -0400 Robert Boyle <robert@tellurian.com> 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
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On Sun, 7 Sep 2008, Bradley Urberg-Carlson, VISI wrote:
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). Yes, that'll work fine.
You can also use DWDM mux to mux down 1529.53/1530.33/1531.13 and put them all into 1530 channel. (Same with 1550 channels). http://www.nanog.org/meetings/nanog38/presentations/pilosov.pdf http://www.nanog.org/meetings/nanog37/presentations/4-pilosov.pdf
participants (5)
-
Alex Pilosov -
Bradley Urberg-Carlson, VISI -
Kevin Blackham -
Michael K. Smith - Adhost -
Robert Boyle