The simulation code you are given treats the Ethernet as a star =
topology LAN with a central repeater and a line to each node. All =
traffic appears on every line. The simulation assumes that the longest =
distance from one station to another across an ethernet is 400m, and the =
signal travels at 80% of the speed of light, which is 300 million metres =
per second. Determine D for this network (D is the propagation delay =
across the network).=20
Conduct simulations of this network at 10%, 40%, 80%, 95% and 120% =
nominal utilization. Utilization is the proportion of the time that the =
ethernet is carrying successful packets. The nominal utilization is the =
utilization which would be achieved if all packets were successfully =
carried. For example, 40% nominal utilisation will be achieved when =
packets arrive at the rate 0.4 * 10,000,000 / (250*8) =3D 2000 packets =
per second. Some of these factors mean that the actual proportion of =
time during which the network is busy could be greater or less than 40%. =
In each of these simulations, you should measureor investigate:=20
a.. the effective utilization rate (only count bits successfully =
sent),=20
b.. the rate at which packets are rejected by the ethernet access =
layer (also known as the packet loss rate),=20
c.. packet throughput (ie. 1 - the loss rate),=20
d.. collision rate (collisions per packet),=20
e.. average number of packets involved in a collision,=20
f.. the average number of collisions experienced by a packet given =
that it experiences one collision, and=20
g.. the average delay experienced by a packet.=20
In addition, repeat the simulations at 40% and 80% for a network with =
100 times the propagation delay, as might be experienced if the network =
was extended over too wide a physical distance.=20
Note that the package length in the program is in bytes, and some =
figures may not be explicitly designed in the program, it requires you =
to investigate from the program execution statistics.=20
Submission Requirements=20
The submission should be in the form of essay. In the essay, you should=20
1. determine the number of bits which can be transmitted in the time D, =
given that the transmission rate of the network is 10 Mbit/s, the =
average packet length is 250 bytes, and the nominal utilization level of =
the network is 80%.=20
2. tabulate or plot these resultsfor the network of LAN at different =
nominal utilization. Also, you should comment on the significance of the =
results for the successful management of an ethernet LAN.=20
3. tabulate or plot the results for the network (ie, 100 times the =
propagation delays) but only at 40% and 80% of the nominal utilization. =
You shall comment on the implication of these experiments
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