Hello,

In RFC1131, the sample value of the IngTranDelay is 1 second. Could someone
tell me that how this sample value is computed. I think that in a high
speed network, a time delay in the order of second, happening in every hop
of forwarding, would cost too much.

Using an example to explain my opnion :) Router a and b are in the same
OSPF routing area. Assuming they are H hops away. Consequently, any LSA
from b to a will take at least H seconds according to the sample
InfTransDelay value. If a is transmitting some files at the speed of 50M
bps to b when b starts to flood its "DOWN_1_second_later" LSA throughout
the area, a will not stop its tranmitting until at least H seconds later.
It means there are (H-1)*50 Mb lost.

A good routing dynamic scheme should be able to make routers adapt
themselves to environment changes very quickly; and this can only be
achieved by a short end-to-end LSA transmitting delay.

In Jim Gray's "the cost of messages", the delay is in the order of eithe ms
or even less. And that paper was published in 1988 ACM.

Best wishes

Ben

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