1. Project Progress Presentation GENERATION OF NS2 TRACE FILES FOR SATELLITE-WIRELESS NETWORKS CS603 - Wireless Communications & Networks Summer II 2003 Wasim Mahmoud El-Hajj Hernan H. Aranda Gomez

2.  NS2 doesn’t support the implementation of both satellite and wireless networks at the same time. Satellite links differ from wireless links in the following respects: What’s the problem? 1.Transmit and receive interfaces must be connected to different channels. 2.There is no ARP implementation, which indicates that there is no hierarchical addressing. 3.There is no radio propagation model.  To attach number of wireless nodes to a base station, we have to specify IP addresses to each of the nodes and associate them with the base station. This is done using hierarchical addressing by dividing the nodes into domains and clusters. So if a wireless node wants to send a packet to another node outside its domain, it has to send the packet to its base station and the base station will route it to the particular destination node. If the destination node was part of a satellite network, then NS2 will fail to deliver the packet because of former reason (# 2 above).

3.  The problem can be fixed by extending the NS2 code in order to make the satellite network support hierarchical addressing and radio propagation.  Also, we can take the two separate trace files and try to combine them using different approaches, defined later, to form a new trace file that shows the two networks communicating together.  We are going to implement the second approach and generate a new trace file that combines the two networks.  Our implementation will act as a bridge between the two networks and the new trace file will show packets traveling from one network to the other with transparency.  The new trace file will not be a NS2 output, in other words, the satellite- wireless network will still not work in NS2. But, this trace file will be the closest simulation obtainable to a satellite-wireless network. What’s our goal?

4.  The receiving terminal in the satellite network and the base station in the wireless network will be clones of each other. That is, when the receiving terminal receives a message from the satellite network, the base station is going to route this message to the destination node in the wireless network. On the same hand, when the base station receives a message from the wireless network, the receiving terminal at the satellite network will send this message to its destination node.  The former paragraph suggests that the user specifies a source node in the satellite network and a destination node in the wireless network, and vice versa. So, we ask the user to add the following lines at the beginning of each file: How are we going to reach our goal? # application # “source” “destination” “start time” “interval/window” “packet size”. #.

5. Let’s look at an example… # UDP # node1 node1 3.0 50.0 500 # node2 node3 10.0 60.0 500 # TCP # node4 node2 3.0 32 500 # node5 node5 10.0 32 500 #. node2 clones base_station1 terminal1 terminal3 WIRELESS NETWORKSATELLITE NETWORK node5 base_station2terminal4 node1 node4 node5 node3 node1 node3 node4 node6 terminal2

6.  The main problem that we will face in combining the trace files is that both of them share same node names.  To solve this problem we will change the node names in both trace files. Generating the final trace file Satellite:n01 … n999 s01 … s999 Wireless:n01 … n999w01 … w999  We will merge both trace files and sort them according to time. Everything will be executed from a script file, so the user will not worry about running the source codes or our program to get the final trace file.