Scheduling Algorithms for GS
Characterize source by “average” rate and minimal burst size using token bucket -- also called Linear Bounded Arrival Process (LBAP)
Conformance if there is always enough tokens whenever a packet is generated. Non-conforming packets are dropped or tagged
Use WFQ to reserve bandwidth at average rate
- may use less bandwidth than with peak rate
- can get an end-to-end delay guarantee (isolation)
- for low delay bound, may need to reserve at high rate (coupling)
- implementation complexity (timestamp calculation and priority queue)
- can waste bandwidth; worst-case rarely happens!