Code review comment for lp:~martin-lp/hipl/update_ack_handling

On Wed, Aug 10, 2011 at 7:40 PM, Christof Mroz <email address hidden> wrote:
> You introduce the lower bound in this branch, but other than initializing it to zero it's not updated. Don't you need to adjust it upon succesfully processing the update tagged with the smallest ID?

It gets updated in check_and_update_ack_id_bounds() with every incoming valid ACK. The problems that may be as it is:
- it gets updated before the HMAC check is performed, a retransmission would still be accepted though so this should not make trouble.
- out-of-order ACKs get dropped. Say you send two update packets with SEQ x and x+1 and you receive the ACK for x+1 first, it would update the lower bound and ACK for x would be dropped. This is non-trivial to fix though. Seems to be ok with the RFC in any case: "The semantics are such that the receiver MUST acknowledge the UPDATE, but the sender MAY choose to not care about receiving the ACK."