Hello I am new to using ns-2 and have a few questions about getting my simulations right. Any feedback/comments would be helpful.
1) In a particular topology of the network, I scheduled a particular node to send lots of identical (TCP) traffic to various nodes (infact all other nodes on the network). The resulting trace file shows that some destinations receive (or are sent) more packets than others. Why is this? Considering that all the links are of the same speed, and the node which gets the most packets is not on the same segment of the sending node? Infact, the destinations nodes on the same segment as the sending node receives and replies with much fewer packets. Also, there is a particular node which received considerably a lot of packets (more than 50% of the entire traffic). Judging by the topology and the design of the network, there is no reason why it should have? Any thoughts on the above - particularly on the random nature of the distribution of such traffic in ns-2? 2) A question related to the above scenario, where all desitnation nodes where scheduled for traffic for a total of 1 second. Now, the resulting trace file shows that traffic to some nodes is only sent/received for a much shorter amount of time than others. A question: could we control traffic behaviour specially in terms of (1) number of packets? (2) duration of packet exchange? So, for example a node A is scheduled to send exactly 100 packets (or exchange packets for a duration of 15 seconds) to a particular node B? If such is scheduled, would this be affected by - topology? - speed of the links? - congestion/load? Any comments are much appreciated. Thanks Siraj
