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Re: [ns] Link delay, what is it?



On Thu, 7 Jun 2001, Huan Pham wrote:

> Propogarion Delay = Distance / (3*10^8 km/s)

metres per second. in a vacuum.

in copper it's around 2x10^8 m/s.

Believe it or not, this matters to some people.


> But when I mentioned "processing time" I meant processing time at the
> physical layer (not queuing delay), i.e the time transmiter and receiver take
> to process the signal at physical layer which may involve Segmentation and
> Reassembly, FEC ...  until it can pass the data on to the network layer. This
> is a more significant delay than the Propogation Delay.

ns wasn't intended for and isn't good at that level of realism, and
stuff like interleaving gets ignored. If you really want that level of
realism, you might want to try playing with Opnet.

L.

<[email protected]>PGP<http://www.ee.surrey.ac.uk/Personal/L.Wood/>