is it possible to conect the link between 10g and 1g sfp

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Mar 1st, 2012
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we have the following system in site 1 and site 2, is it possible to connect one side fiber to 10g and the other side to 1g. the distance between site is 11 km. we need to work this as we want this as a temporary setup till our new new switch becomes up.

site 1



Cisco X2-10GB-ER


site 2



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Joseph W. Doherty Sat, 03/10/2012 - 03:33
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My understanding is, 10gig and 1gig don't mix, except on the later SFP+ ports that support gig/10gig (and those still require both sides to operate at the same speed.

Depending what sup you have in the 6509-E, you might be able to use its SFP gig port to attach to the other side's 6408A.

Kishore Chennupati Sat, 03/10/2012 - 03:43
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AFAIK, you cant connect a 10G to a 1G fibre and also you cannot hardcode the speed on SFP ports. So as joe suggested either connect your 1G-1G or a 10G to a 10G.

you can connect a 1G(SFP) to a 100mbps and hardcode the 1G port if you use GLC-T transceivers



Marvin Rhoads Sat, 03/10/2012 - 10:30
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Optical connections need to be at the same speed at both ends. There is no autonegotiation of speed in the optical realm nor is there the abiliity to hard code the speed of an optical transceiver to other than its intended speed.

At site 1, if you have a Supervisor Engine 720, you can use one of its SFP ports with a GBIC. Assuming single mode fiber between the sites, a 1000Base-EX or -ZX transceiver would be required. See the data sheet here.


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