Military Communications and Information Technology: A Trusted ...

Chapter 3: Information Technology for Interoperability and Decision...
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Success ratio
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
No errors PER churn PER, churn
(a) Success ratio
14
Byte sent node -1 s -1
12
10
8
6
4
2
0
No error PER churn PER, churn
(b) Traffic per node
Figure 3. KadScribe in the simulated environment
IV. Evaluation
The OMNeT++ simulation framework [21] with the OverSim framework [2]
was used to simulate the network and to analyze the protocol. The implementation
of KadScribe was done within the simulator as a separate module. The network
consists of 1024 peer-to-peer nodes and all peers are directly interconnected.
The simulation features the IP and UDP protocol, the lower layers are abstracted
by an error and churn model. The reasons to do so is the complexity of a wireless
simulation and the loss of generality of the results. The use of a churn and error model
also simplifies the comparison of the results with other publications. The churn
process was modeled as Weibull-distributed as described in [20] with a reduced
mean lifetime of 60 minutes. The churn model is supposed to cover all the cases
where user equipment drops the connection against the will of the user, e.g. because
of mobility or low battery. The connections between each peer have a constant