Cisco SFP Transceiver compatibility with 3Com Fiber

[networknoobs]

Hi, I was assigned for a small scale project last week and the main purpose is to interlink three sites together using fiber connection. Here's the details

i. Main building (Cisco 3560 with SFP) to Site_A (3Com Superstack 3300 100Mbps Fiber)

ii. Main building (Cisco 3560 with SFP) to Site_B (3Com Superstack 3300 100Mbps Fiber)

iii. Main building (Cisco 3560 with SFT) to Site_C (Cisco 3560 with SFP)

The module is the SFP1000Base-SX & SFP1000Base-LH; the connection between main building and Site_C is a no brainer, up and running fine. But when I tried to connect main building to Site_A and Site_B; bump into problem whereby Cisco SFP detect no signal at all (down; down). I tried to scale down the speed and to realise that the SFP module does not allow me to down scale the speed to 100Mbps in order to match with the 3Com superstack fiber connection. I check my fellows friend and they said perhaps the SFP is only able to run at 1Gbps; not able to scale down; not able to change the duplex mode also...

What I want to know is; is there any way I can connect it up without much problem? Since the SFP transceiver is purchased; is there any other complimentary device that can make the connection works?

Thanks a million

[networknoobs]

anyone?

[anthonym]

I have had success using the Cisco SFP to conenct to 3Com 1Gbps modules, two of them infact.

According to this page http://www.cisco.com/en/US/products/ps6578/index.html

Does the product name of your SPFs contain FE or GE?

You need different SFPs for Gb and Fast Ethernet.

[networknoobs]

suppose they should purchase FE SFP; but ended up they purchased GE SFP, which doesn't match in speed (Cisco side=1Gbps while 3Com side=100Mbps). At first they thought it can be scale down just like UTP port; but when I'm in the SFP interface, I can't seems to issue any command like "speed 100"...it means the SFP only operates at 1Gbps...btw...it can't set the duplex mode as well aint it?

I guess I need to ask them to buy the correct SFP module before start the job again...thanks bro