Hi Murat & others,

Do you have insertion loss measurements for the individual or combined paths ?  
Any measurements should be taken at 1550nm.

EDFA Amplifiers at your intermediate points could work - you would probably get 
away with EDFA at one point - 80km plus 40km should be quite OK. Depending upon 
the EDFA Amps and their input power range, you could even boost the signal as 
you receive it at each end - after 120km - avoiding intermediate active gear 
altogether.

If the fibre is not too poor, you may also be able to avoid EDFA or 
intermediate re-gen all-together - I'd suggest trying it as a single 
"patched-through" link. You need to keep in mind that chromatic dispersion can 
become an issue for 10Gbps at a distance >= 80km. We've had a 10Gbps link 
recently of > 110km that didn't work with an 80km optic at 1560.61nm (even 
though the received power was OK), but worked with an 80km 1530.33nm optic - 
(dispersion is reduced at the shorter wavelength).

If I was trying this, I'd first try a pair of 100km rated 1550nm optics like 
these:
http://www.flexoptix.net/en/produkte/transceiver/xfp-zr-transceiver-10-gigabit-stm64-sm-1550nm-100km-25db-ddm-dom.html

Or if dispersion turns out to be the limiting issue, then there is a good 
chance that a 1470nm version of the CWDM XFP part could do the trick (lower 
chromatic dispersion at 1470nm than 1550nm, but perhaps slightly higher loss)
http://www.flexoptix.net/en/produkte/transceiver/xfp-cwdm-transceiver-10-gigabit-sm-1270-1610nm-70km-23db-ddm-dom.html
- 1470 will be out of the range where EDFA Amps can help you, but these two 
options could avoid EDFA all-together.

I'd try one or both of these options - If the link comes up, you can know how 
much margin you have by reading the DoM stats, or you could check that it still 
works after inserting say a 2dB attenuator in both the TX and RX path.

Its so much simpler to try it with the longest range optics you can find at 
each end that I'd strongly favour trying that first - before looking at re-gen 
at one or both of the intermediate sites, or Amplification either at each and, 
or at one intermediate site.

Good Luck!

I'd be interested to hear what you try and how it works for you.

Tim.


Tim Rayner
Optical Engineer, AARNet Pty Ltd
street address: Building 9, Banks Street, YARRALUMLA ACT 2600
postal address: GPO Box 1559, CANBERRA ACT 2601
t. +61 2 6222 3575 f. +61 2 6222 3535 e. [email protected]
w. www.aarnet.edu.au
Network Faults (24x7): 1300 APL NOC (1300 275 662) or [email protected]

important
This email and any files transmitted with it are confidential, and the rights 
of confidentiality in such information are not waived or lost by its mistaken 
delivery to you. Any dissemination, copying, use or disclosure of the email 
and/or such files without the permission of AARNet, or the sender, is strictly 
prohibited. If you have received this email in error, please contact the sender 
immediately and delete all copies of this transmission.

________________________________________
From: cisco-nsp [[email protected]] on behalf of Ivan 
[[email protected]]
Sent: Saturday, 6 September 2014 12:14 PM
To: [email protected]
Subject: Re: [c-nsp] Connecting PoP's with long distance

Hi Jared,

This is something I have also been looking at. Is there any particular
brand of XFP you have had success with?

If we take the Cisco "80km" ZR we have TX 0 to 4 dBm and RX -7 to -24
dBm - worst case 24dB budget excluding splices, patches etc. Assuming
0.2dB/km 120km would be right on the limits. I would like to have some
buffer.

Thanks

Ivan

On 5/Sep/2014 1:32 a.m., Jared Mauch wrote:
> You should be able to do 120km with a ZR XFP @ 10G without anything.
>
> If you later want to add equipment to the sites, you can look at doubling 
> your optics and something like this:
>
> http://www.perle.com/products/10-Gigabit-Standalone-Media-Converters.shtml
>
> - Jared
>
>
>> On Sep 4, 2014, at 5:36 AM, Murat Kaipov <[email protected]> wrote:
>>
>> Hello Guys.
>>
>> I need connect two PoP's with 10G links. Distance between PoP's nearly
>> 120km. We have fiber optic between PoP's with two regeneration points
>> located nearly in 40 km between each other. We have not DWDM. Can you advise
>> some equipment (May be like EDFA) for fiber optic regeneration points
>>
>> Scheme like this
>>
>> PoP-1 ---40km---[Regeneration point1]---40km----[Regeneration
>> point2]-----40km------PoP2
>>
>> Thank you.
>>
>> _______________________________________________
>> cisco-nsp mailing list [email protected]
>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>> archive at http://puck.nether.net/pipermail/cisco-nsp/
>
>
> _______________________________________________
> cisco-nsp mailing list [email protected]
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
>
_______________________________________________
cisco-nsp mailing list [email protected]
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/
_______________________________________________
cisco-nsp mailing list  [email protected]
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/

Reply via email to