Extended Burst Methodology
- Comes into play if there are no tokens in the bucket
- Allows the stream to borrow tokens
- A packet arrives that needs to borrow “n” tokens then a comparison is made between two values:
1) the extended burst parameter value
2) 'compounded debt', where 'compounded debt' is computed as sum of a_i, where i indicates the ith packet that tries to borrow tokens since the last time a packet was dropped, and a_i indicates the 'actual debt' value of the stream after packet i is sent (if it is sent). (note that 'actual debt' is simply a count of how many tokens the stream currently has borrowed).
If 'compounded debt' is greater than the extendeed burst value then the packet is dropped. And note that after a packet is dropped, compounded debt is effectively set to 0 and the next packet that need to borrow will have a new value computed for 'compounded debt' which will be equal to 'actual debt'. So, if 'actual debt' is greater than extended limit, then all packets will be dropped until 'actual debt' is reduced via accumulation of tokens.