CWDM module compatibility

[rottenberg]

Hello,

We are having an old 6513 device with WS-X6502-10GE and one 10GBase-ER module (not sure but looks like this module is WS-G6483).  10GBase-ER module is connected to CWDM-MUX-8A. This device will be migrated to WS-6513-E with one WS-X6704-10GE and XENPAK-10GB-ER+. The problem is that I can not find any statement (on Cisco web site) whether it is possible to use XENPAK-10GB-ER+ with CWDM technology. I know that XENPAK-10GB-ER+ is official replacement module for WS-G6483, so it looks good, but can somebody advice whether using XENPAK-10GB-ER+ with CWDM is possible?

Any answer is very appreciated.

Regards,

Zdenek

[Tom Randstrom]

Unfortunately, the 10G-ER or ER+ module will not operate with a CWDM-MUX-8A, without the use of a transponder device to convert the signal to a CWDM wavelength that matches one on the MUX-8A.  Both CWDM or DWDM muxes require that the optical input be at the same operating wavelength/frequency (sometimes refered to as color)  as in input port.  Thus, optical transceivers are offered in multiple wavelengths for CWDM and DWDM networks.  This DATA SHEET provides an overview of a CWDM system.  The 10G COMPATIBILITY DOCUMENT outlines 10Gbps optical transceiver compatibily by platform module; not all platforms support all optical modules.    

Let us know if you have other questions. 

[rottenberg]

Hello,

Thank you very much for your answer. I am not an expert regarding the fibre optic, so please be patient with my next question. As I know that CWDM systems typically provide 8 wavelengths, separated by 20nm, from 1470nm to 1610nm. XENPAK-10GB-ER+ is using 1550nm wavelength which fit exactly to one of eight wavelengths provided by CWDM. So, why transponder is needed?

Regards,

Zdenek

[Tom Randstrom · Accepted solution]

Zdenek,

The CWDM / DWDM transceivers are designed with optical components with a narrower operating frequency range than a standard transceiver (like an ER).  If you were using a wideband WDM multiplexer (2 channels, one at 1310nm and one at 1550m, the ER transceiver could be used (although the link would be limited by the optical link length supported by the 1310nm transceiver).  

If your Cisco line cards support the 10Gbps DWDM optical transceiver modules, the Cisco Enhanced Wavelength Division Multiplexing Product line (specifically the EWDM-MUX8= multiplexer) may be the solution for you.  At this time, Cisco does not have 10Gbps CWDM optical transceivers.  

I hope this helps!

[rottenberg]

Hello Tom,

Thanks again for your perfect reply. It is much appreciated.

Regards,

Zdenek

[Eduardo Lucas]

Hi all.

I can see now that Cisco have CWDM 10 Gigabit Ethernet SFPs like for example the CWDM-SFP10G-1570=...

Does the CWDM-OADM4-2= (or the rest of CWDM family modules) allows the use of this  10GE CDWM SFP without compatibility issues?

[Tom Randstrom]

You can use the new 10G Ethernet SFPs with the CWDM family of multiplexing modules.

Be aware that the 10G CWDM SFPs do not have the same link reach that the 1G CWDMs SFPs have.  If you are installing the 10G CWDM SFPs in a network where 1G CWDM systems were initially engineered, confirm that the link loss of the system meets the link budget of the new 10G CWDM SFPs, or your link may not function.

[RWTull]

The CWDM / DWDM transceivers are equipped with a narrower operating frequency range of optical components than a regular transceiver (like an ER). The ER transceiver could be used if you were using a wideband WDM multiplexer (2 channels, one at 1310 nm and one at 1550m (although the connection will be limited  by the length of the optical link provided by the 1310 nm transceiver). In CWDM technology, a maximum of 18 wavelength channels ranging from1270 to1610 nm are used to relay the signal. Add /Drop Mux/ Demux modules can used here EWDM MUX8= multiplexer) could be the solution for you, Cisco does not have optical transceivers with 10Gbps CWDM at this time you can read more about adding the Drop MUX/Demux module: https://www.versitron.com/blog/discussion-on-cwdm-muxdemux-modules-small-form-factor-plug