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does a switch to switch extend the distance

from the MDF (which has a 3550G) we connect to another switch in a remote building. If we connect the switch in the remote building to a 3rd switch in a more distant building does the switch in the middle 'regenerate' the signal so that the distance limit of 550 meter for gig over fiber can be overcome? in other words, does the distance limit 'start over' by the affect of the switch in the middle?


Re: does a switch to switch extend the distance


yes, this is possible. A switch will internally convert the optical signal into electrical signals to transport frames across the backplane.

The length limitation is basically given by signal-to-noise ratio and dispersion (i.e. physics) on the fiber. A receiver can not detect bits properly, if the fiber is too long, i.e. the signal is too degraded.

As a switchport creates a "brand new" optical signal the limitation only applies to a single switch to switch connecting fiber.

In your case you could potentially go even further (keeping in mind spanning tree limitations).

Hope this helps!

Regards, Martin

Re: does a switch to switch extend the distance

Switches, Hubs, and Routers amplifies ethernet signal.

In your case, why don't you try SM Fibre which can cover long distance rather than managing another switch in the middle?

3550G support 1000BASE-LX/LH GBIC (WS-G5486) that can cover up to 10KM