How does dMLP detect lost fragments?
• Sequence numbers: If you are waiting for a fragment with sequence number N to arrive, and all the links receive a fragment with a sequence number higher than N, you know that fragment N must be lost, because there is no way it could legally arrive behind higher numbered fragments on the same link. • Timeout: If you sit too long waiting for a fragment, you will eventually declare it as lost and move on. • Reassembly buffer overflow: If you are waiting for fragment N to arrive, and meanwhile other fragments (with sequence numbers higher than N) are arriving on some of the links, then you have to park those fragments in a reassembly buffer until fragment N shows up. There is a limit to how much you can buffer. If the buffer overflows, you again declare fragment N as lost, and resume processing with whatever is in the buffer.
