Table 1: Summary of notations.


Number of videos in the system
Access bandwidth of the central video server (bits/s)
Proxy size (in bits)
Bandwidth for broadcasting (bits/s)
System arrival rate (reqs/s)
System service rate
Popularity of video m
Number of quality levels of video m
Probability of customers requesting th quality of videos
Arrival rate for the dedicated streams (reqs/s)
Average rate of the dedicated streams (bits/s), replication and no broadcast
Streaming rate of replicated video m having th quality level (bits/s)
Size of replicated video m encoded into th quality (bits)
Streaming rate of layered video m having th quality level (bits/s)
Streaming rate of layer j of video m (bits/s)
Size of layer j of video m (bits)
jth quality of video m
bProxy cache map matrix,
eCoding approach instance,
wBroadcasting map matrix,
oCache-Broadcast map matrix,
Crossover rate of GA
Mutation rate of GA
Population size of Gas
th quality level