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Flow Control & HOL Blocking

hi together,

i've been searching severals hours in internet and at cco but what i found didn't made me satisfied.

Maybe someone is able to help me with my questions...

here they are.... :)

the default time for pause time by annex 31b is 512 bit times - is there any change in cisco's defaults in competition with this value ?

what happens in detail during the 30 to 35 seconds of link down when i change the flow control status of an interface ?

are flow control and hol blocking able to influence each other ?, say is it possible to get a large delay by using flow control and having an oversubscribed backplane ?

or am i right to say that a packet in one of the queues cannot be influenced by flow control ?

be sure i'd be so thankful for a few ideas or links about that...

kind regards

Chris Kulinski


Re: Flow Control & HOL Blocking

I think using flow control in catalyst switches provides some delay since it sends a special packet called pause frame to the remote end asking the remote to stop sending for a period of time.But if we are able to change the default pause time, then we can reduce this delay factor.(Low Pause Time, low delay)