Traffic Shaping - Leaky Bucket Algorithm

Consider a leaking bucket with a small hole at the bottom. Water can only leak from the bucket at a fixed rate. Water that cannot fit in the bucket will overflow the bucket and be discarded.

Turner's (1996) leaky bucket algorithm enables a fixed amount of data to leave a host (enter a subnet) per unit time. It provides a single server queueing model with a constant service time.

If packets are of fixed sizes (such as 53-byte Asynchronous Transfer Mode cells), one packet may be transmitted per unit time. If packets are of variable size, a fixed number of bytes (perhaps multiple packets) may be admitted.

The leaky bucket algorithm enables an application to generate traffic which is admitted to the network at a steady rate, thus not saturating the network.