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New Member

problem with conecting fiber convertar to cisco

i tring to connect convertar OVISLINK MC1000TSC ( 1000 base-t to 1000 base-sx multi-mode(mmf) with sc connector to a cisco switch( catalyst 2950c-24) but it doesn't work.

so anyone has any information about that it would be nice to help me with it.


Re: problem with conecting fiber convertar to cisco

Are you plugging it into a Gig port on the 2950?

Since the 1000SX is Gig only, I don't think the copper port will downshift to 100BASE (on the converter).

You can try hard-setting it for auto or fixed parameters, but I'm pretty sure you need it to go into a Gig copper port.

Good Luck


New Member

Re: problem with conecting fiber convertar to cisco

I am plugging the fiber patchcord from the Fiber Gig port in the cisco 2950 the the fiber Gig port in the converter and it doesn't work.


Re: problem with conecting fiber convertar to cisco

The two fiber interfaces on a WS-C2950C-24 switch are 100Base-FX which is Fast Ethernet (100 Mbps).

The fiber interface on your media converter is 1000Base-SX which is Gigabit Ethernet (1,000 Mbps).

They do not work together, because they use two different signaling methods. The only thing they have in common is that they both use multimode fiber optic cable.

If you need to connect a fiber port on the Catalyst 2950C-24 switch to something else, you need to use different equipment. Either a 100Base-T to 100Base-FX media converter; or a 10/100Base-T to 100Base-FX bridging media converter.

For best performance, set the 100Base-FX fiber ports to full duplex. That will give you your best throughput vs. half duplex; and you will be able to transmit over longer distances: 2km for full duplex, vs. 416m for half duplex.

If the fiber ports are manually set to full duplex, the copper ports should be as well. Don't leave it to chance; that is to say, don't depend on autodetection on the media converters.

Re: problem with conecting fiber convertar to cisco


I just happen to have similar problem. 2 x Fibre, one is okay the other is not. After I ask my cabling contractor to re-test the fibre end-to-end, they found that the problem is the fibre cable.

Mine is 3750-48-TS with GLC-SX-MM.

Take note that the converter pin should be set to auto/auto and the switch ports as well.