Simulation Assignment 2 - MAC and Network Capacity study
Date: Tuesday, March 23
I. Medium Access Control
The goal of this work is to study the performance of IEEE 802.11 MAC protocol under highly-loaded and lightly-loaded conditions,respectively.
Please set up the simulation scenario as follows,
1. This is a network consisting of a base station (Server node) and multiple static nodes (client).
2. Ensure that the transmission range of every node is at least 100m and at most 120m. Place all nodes such that they are within the transmission range of one other. In other words, no hidden or exposed terminal
problem in this network.
3. Constant-Bit-Rate is chosen as upper layer application.
Each client node starts sending data from second 0, and transmission interval is 4ms. The packet size is
512 bytes. Assume that each node has an infinite number of packets to send.
4. The simulation time is 5 seconds.
5. The propagation model is FREE-SPACE model.
6. UNIFORM node placement.
7. RADIO-RX-TYPE SNR-BOUNDED.
8. Set TX-POWER so that the desired transmission range is achieved.
9.ANTENNA GAIN 0
10. RX-SENSITIVITY -81.0dBm
11. Set the MAC protocol as "MAC802.11".
Change the number of client nodes from 1 to 6, in step of 1. Observe how the network performance is going to change in terms of the total throughput of base station and end-to-end delay averaged over all client nodes.
system throughput: total number of packets received by the base station
1. Brief description of your simulation procedure.
2. Plot the node placement for a network consisting of 6 nodes
3. Plot number of clients vs. system throughput
4. Plot number of clients vs. end-to-end delay averaged over all nodes.
5. Analysis of your plots to discuss the benefits or disadvantages of 802.11.
II. Study of End-to-End throughput in a multi-hop Ad-Hoc Wireless Network
In this task, we are going to study how end-to-end throughput changes with the increase of hops between source and destination. This simulation will help you understand the space reuse in network wireless medium utilization and multi-hop routing, which determines how well the network scales as we expand the network.
Set up the network scenario as follows.
1. Set up a chain network consisting of N+1 nodes, node 0 to node N.The distance between two
neighboring nodes is 100 meters.
2. Node 0 is the source node of a CBR application that continually generates packets for node N
CBR 0 N 0 1500 10MS 0 0
3. TX-POWER 2.5dBm
4. All other radio parameters are the same to the value defined in task 1.
5. Set simulation time to 3 seconds.
6. Use ROUTES.IN to define the static routing scheme. In our simulation, node x always relay packets to
node x+1 until packet arrives at destination. The format of ROUTES.IN is as follows, src dest_ip nexthop_ip
NOTE: In qualnet, the dest and nexthop has to be represented with ip address. E.g., if the subnet address is 192.0.0.0. and you want to define a static route from node 1 to 3 (192.0.0.3) through 2 (192.0.0.2), the entry in the route config file is:
1 192.0.0.3 192.0.0.2
7. Use 802.11 as MAC protocol.
In a fixed network topology,change your CBR definition by changing "interval" from 10ms to 100ms. Repeat your simulation to find out the optimal "interval" value which achieves maximum end-to-end throughput. Plot the curve of pkt interval vs. end-to-end throughput.
Increase the number of nodes in the chain network by changing N from 1 to 8. At the end of your simulation, you should have 8 plots one for each of 8 network topologies.
Comment on how the end-to-end throughput changes with the increase of hops from source node to destination node.
end-to-end throughput: total number of packets received by node N
1. 8 curves of pkt interval vs. end-to-end throughput for all 8 network topologies.
2. Analysis of how the end-to-end throughput changes with the changes of packet generation rate
and number of hops between source and destination.
III. Study of network capacity in grid network
In this task, we are going to study the impact of space reuse and route lengths in grid neetwork.
Set up the network scenario as follows,
1. Set up a grid network consisting of 4, 9 or 16 nodes. The distance between two adjacent nodes is 100m.(you need to do simulation for
all 3 scenarios)
2. Static routing is applied. ROUTES.IN could be downloaded from here
3. Set simulation time to 10 minutes.
4. Use 802.11 as MAC protocol.
5. Define CBR application as follow:
CBR src dest 0 1500 2S 0 0
6. Set up other parameters the same as in task2.
In your simulation, study the three grid topologies illustrated in above figure.
Each node randomly chooses its destination among all other nodes in the grid network at the beginning of simulation, and keeps sending packets to this node through the whole simulation. The upper layer CBR packets are routed to its randomly determined destination node by static routing scheme. It's acceptable that more than 1 node choose the same destination node.
At the end of the simulation, calculate system throughput and end-to-end delay averaged over all nodes.
System throughput: total number of packets that have been successfully transmitted to destinations in the
average End-to-End delay: End-to-End delay averaged across all nodes
1. Plot average system throughput vs. size of grid.
2. Plot average end-to-end delay vs. size of grid.
3. According to your simulation result, analyze how the network performance changes as grid network