Figure 4.21 shows the average delivery cost as a function of number of receivers per LMR
Again this result shows that Xcast faces the scalability problem where the other three
considered protocols are better than the Xcast protocol. The high delivery cost for Xcast
happens because of the big packet size delivered through the links in this protocol. The big
size comes from the protocol consideration of encoding the receivers address in the packet
header.
600
SREM
Figure 4.21 Average delivering cost as a function of number of receivers per LMR
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