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New Member

ISL - Questions

Hi Sirs:

* Is ISL a tagging method or a protocol? Please explain the difference for each concept.

* ISL Header includes 5 bytes of the Multicast MAC Destination Address. What about the sixth byte? Is´t filled with zeros?

* ISL Header includes a "USER" field, with 3 priority bits for ethernet frames. What ISO command is used to set up these bits? Are these bits only informative or have some QoS mechanism associated in both ports of the trunk? Please comment

  • Other Network Infrastructure Subjects
New Member

Re: ISL - Questions

I'd say it's a bit of both.

It is a protocol defining how to tag packets, and thereby it is also a tagging method.

My knowledge is not profound within ISL and so I refrain from answering to the latter questions.

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