Isaac Marino Bavaresco ha scritto:
> I use two sequence numbers, one for the packet and other for the command
> itself. It is useful for networks with routing where the packets may
> arrive out of order or multiple times due to routing problems.

interesting...

> If the sequence number of the arriving packet if less or equal to the
> last received one, just ignore it. If it is newer (inside a
> predetermined window), check the command sequence number. If the command
> sequence number is exactly equal to the last one, just resend the last
> answer but don't execute anything. If the command sequence number is
> newer (inside a window limit), execute it, send the answer and store the
> answer.

...worth investigating more. I agree on the second part, but why having two?

> There must be provision for a synchronization packet which is not
> sequenced itself.

could you explain more this one?
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