Each link ij is associated with the corresponding allocated
bandwidth for the video traffic (gii), the error rate observed on the link (eii), as well as the
corresponding delay due to the video queue ( queue
ij d ). Within the reserved time for the video
traffic, each link exhibits a certain throughput given the chosen modulation strategy. Video
packets are lost due to the experienced BER. This error is due to noise and interference in
the wireless medium stemming from background noise, node mobility or simultaneous link
transmissions. In addition to this error, under delay-constrained video streaming, packets
are discarded due to delays incurred in the transmission, e.g., the queuing delay of each
link. Notice that Figure 5.2 displays different connectivity structures for the network
topology, as specified by the indicated links. Obviously, the tightly-connected multi-hop
mesh topologies T1 and T2 of Figure 5.2 offer more alternative paths for the video traffic
that topology T3; however, the overall reserved time across the various nodes of the
network is also increased. In general, the decision on the connectivity as well as the
number of nodes participating in the video streaming session depends largely on a number
of system-related factors that transcend the video streaming problem (e.
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