Hi Team,

Thanks for support/

Operational Existing Scenario

6509[GLC-SX-MM] ---> LC-MM patch cable-ST --------> MM fiber ------------> ST-MM patch cable-LC-----------> 3750 Stack[GLC-SX-MM] ------> 1G

Building 1  ------------------------------------------------> Max.300 Mtr -------------------------------------------> Building 2

Unsuccessful attempt to Implement

4506-[X2-10GB-LR]------------->SC-MM patch cable-ST -------------> MM fiber ----------------->ST-MM patch cable-SC ------> 4506-[X2-10GB-LR]

Bulding 1 --------------------------------------------------------> Max.300 Mtr -------------------------------------------- > Building 2 

This diagram would help you to understand the issue faced by us.

Kindly advice,

Vaibhav Shirkul

If your 300 link is working then GLC-SX-MM is going over 50micron MM cable. (Can go upto 500 to 550m over OM2 and 1000m over Om3) Do you know what MM cable you have OM2 or Om3?

Problem at 10G is max disatnce on

OM2 MM cable is 70m for SR and 300m for LX4.

OM3 MM cable  300m for SR

If you have this module X2-10GB-LR then you have chosen a wrong module as it is meant for SMF (Single mode). Since your disatnce is 300m max then X2-10GB-LX4 could have given you the link.

You can try deppending on availability/price

1. See if you can get X2-10GB-LX4 (retrun / exchange) and check if that works

2. If you X2-10GB-LR and you cannot return/exchange then try a mode conditioning cable (http://www.cisco.com/en/US/prod/collateral/modules/ps5455/product_bulletin_c25-530836.html) mentioned in the link or similar cable. It is possible that you can get the link (not 100% sure)

Both X2-10GB-LR & X2-10GB-LX4 gives you nearly the same optical budget but i think will be limited by dispersion as LX4 have  has 4 wavelength working at 2.5Gb have EDC(electronic Dispersion Compernsation) whereas LR have 10G so dispersion will be more for LR.

3. Pull SMF cable as you have LR optics.

I dont think there is multimode extender at 10G there are at 1G but not at 10G.

This not neccesasarily true.  While the specs for GLC-SX-MM over 62.5micron say max 220M, we have many links that go over 300 meters (and several patches) with no problems.

This not neccesasarily true.  While the specs for GLC-SX-MM over 62.5micron say max 220M

Thanks! for sharing your expereince. It is wrong to use Max. word so will try not to use it in future. for 62.5MM fiber 200MHz.Km fiber it is possible to get distance of 275m maybe you have that one.

http://www.cisco.com/en/US/prod/collateral/modules/ps5455/ps6577/product_data_sheet0900aecd8033f885.html

There are so many parameters , which tells how far you can go and those numbers are average and it is possible to get more disatnce (They are just assuring you for the least disatnce.)

Optical power for example have a very good range from (-3 to -9.5dBm)

Similary dispersion in multimode fiber depends on how good is graded index profile of the fiber if it is too good you can get more distances.

Thank you.... We definitely appreciate feedback from real world networks!

In many cases, the network may operate outside of the published specifications.  As viyuan700 has pointed out, the assumptions used by the specification bodies are generous so that the links will operate properly over most links.  These "loose" link losses, which include fiber, connector and system margin, plus dispersion effects, result in links that may operate over longer links than outlined by the 802.3 specifications.

There can be two problems with operating links outside the bounds of the Cisco's published specifications; if you need to contact Cisco TAC, you may not receive the support you need because you are operating the system outside the bounds of the published parameters for the device. The other is if you swap out a transceiver, the new transceiver may have a lower transmit power than the previous unit; which may result in a link that doesn't operate properly.

Again, we appreciate the real world feedback.  Keep it coming! 

Tom