Token Bucket
Allows “bounded” burstiness
Tokens generated at rate “rho” are placed in bucket with depth “sigma”
An arriving packet has to remove token(s) to be allowed into the network
A flow can never send more than [sigma + rho * t] over an interval of time t
Thus, the long-term average rate will not exceed rho
More accurate characterization of bursty flows means better management of network resources
Easy to implement, but harder to police
Can add a peak-rate leaky bucket after a token bucket