Hi Experts,
Does anyone know how to calculate propagation delay & transmission
delay?
What's the relation between them and bandwidth?

Sincerely,
Peiyi 
Service Nova Scotia, Canada

"Stone" <wupeiyi2@hotmail.com> wrote in message
news:1159369190.637085.131270@m73g2000cwd.googlegroups.com...
> Hi Experts,
> Does anyone know how to calculate propagation delay & transmission
> delay?

sounds like homework - but a working engineer rule of thumb (which you
probably wouldnt get marks for):

propagation delay is "how long to get a signal from A to B" - often applied
to high speed links (in my case almost always fibre). limited by speed of
light or other signal in the medium.

often this isnt as easy as measuring on a map - you dont know the route, and
a modern DWDM system may have a fair bit of extra compensation fibre
compared to geographic route distance.

Also need the right "speed" - speed of light in fibre is approx 2/3 of
vacuum.

transmission delay is "how long to get there" - propagation delay + delays
in equipment + other relevant delay, such a Q'ing and serialisation.

both terms really are context dependent.

> What's the relation between them and bandwidth?

there isnt one - in a network they are independent variables.

if you are discussing a "connection" using something like TCP, then the
protocol has constraints driven by available bandwidth and end to end round
trip delay.
>
> Sincerely,
> Peiyi
> Service Nova Scotia, Canada
>
-- 
Regards

stephen_hope@xyzworld.com - replace xyz with ntl