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New Member

optical linkup procedure between switches 3500 XL

In our lab we have 2 switches of the series 3500 XL and 2 GBICs (850 nm). If we connect both switches directly we can see both switches via network (ping possible). If we add an DWDM device (optical/electrical multiplexer) into the optical line to extend the distance between both switches there is no connection possible between the switches it means the leds near the GBIC's don't switch to yellow or green, they do nothing. The DWDM device works correctly with GE tester. So I think it's a startup problem. My question is: it's possible to get more information about the linkup procedure ? Which logical or other sequence is minimally necessary that both switches recognize each other.

Can everybody help me ?



Re: optical linkup procedure between switches 3500 XL


Do revert the kinda SFP model being used in the DWDM device and also the model of the same.

is it something inline with 15454 or something in that range ?

Also revert back about the fiber being used to patch up both DWDM and the switch.

AFAIK there r 2 things involved in this connectivity first one is the local connectivity between the switch and the dwdm ,second one is the connectivity between the dwdm device.

if you dont get one out of this you will not be able to get the connectivity between the switches via the dwdm..


New Member

Re: optical linkup procedure between switches 3500 XL


Thanks for answer. After further investigations I found out that both switches send an configuration sequence to find the other side. This sequences are constructed with /C1/, /C2/ configuration sequences according the GE standard. In case of transmission of these configuration sequences over our DWDM equipment this sequences will be sometimes destroyed so that the switches are not able to build up an logical link. The question is: how reacts the switch if it gets a wrong configuration sequence, maybe 1 sequence is lost or /c1/ and /C2/ don't change in the data stream in the demand order.

In summary: the described problem is not an optical one, is't a problem of configuration sequence transmission in the startup phase

Best regards

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