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Re: [ns] link delay



On Fri, 31 Aug 2001, Miss Pennatee Rohitsatian wrote:

> Can anyone tell me that :
> 
> if I set link delay to 5 ms, how long the distance of this link?

it's undefined.

> Does anyone know that in NS, how long of the link delay per one
> kilometer?
> 
> Can I use light speed to calculate the link distance if I know link delay?

that depends.

local speed of light depends on the medium. The ns satellite code uses
speed of light in a vacuum; for copper wires or fibre, you'd need to
use a different speed/permittivity.

And there are many things between the network layer and physical
propagation delay (framing, coding, header overheads) that suddenly
start to matter if you worry about accurate numbers behind distance
and speed.

L.

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