Bin,

 InfTransDelay is not used to _delay_ LSAs flooded out
 of an interface. It is only used to update their Age
 fields.

--
Alex Zinin
Friday, August 03, 2001, 7:44:21 AM, Bin Liu wrote:
> 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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