Dear ns-users,
I would like to build a simlpe ideal network, that transmits packets from
many users and forwards it through a trunk, just like in the case of ATM
access network. If the aggregated traffic exceeds the bandwidth of the
trunk, the (router) node drops the overloading packets. (I don't need
queueing for now).
I want to measure the Packet Loss Probability on the trunk. Right now I have
a UDP network for transmitting the data packets. I use Agent/CBR for traffic
generation. When I run the simulation, a lot of packets are droped right on
the data generating node. I don't understand why.
I use the following principle: a node(user) is connected to the router
through a 64kbps link. The CBR rate and the header for UDP give the 32kbps
average rate. It should mean, that I have an On/Off Bernoulli distributed
random source, that generates data with 64kbps in its On state and with 0
kbps in its Off state. Some packets are dropped right on the source node. I
don't understand why.
All the queue-limits are set to 2, becuase I don't need queueing for now,
and this is the minimal queue-size that makes packet forwarding available.
If anyone could give me a hint, how the queueing modell and packet
forwarding works, that would be great help as well - the manual is not
enough detailed.
64 kbps ------------------------
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|
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0 kbps
I hope someone can help me!
Regards,
Endre
