Re: [core] Comments and questions on draft-jarvinen-core-fasor-02

[Carsten Bormann <[e-mail]>]

>> 
>> I don’t think that is the intention.
>> If the message-id of a received message is the same as the one the server just processed, just discard.
> 
>   Are you saying that retransmissions of the same message may have different message-id values??? 

No, I was trying to say that a recipient discards duplicates, which they detect by them having the same message-id.

> If so, why do we need this new counter to begin with?  The sender could simply use different message-id values in each retransmission, and use that to associate an acknowledgement with a specific retransmission.

This would take away the deduplication feature, which is sometimes needed, and sometimes just saves some work on the part of the server.

>>> In addition, if a retransmission contains updated information, retransmissions will have to be exposed to the application, rather than being handled by the protocol stack.
>> 
>> Right.  That is not the intention.
> 
> Well, if one is allowed to update information in retransmissions, that would be the case…

Again, the point is that a duplicate is not processed, so the sender could not rely on the updated information being seen (in the case the ACK was lost).

> Retransmissions are typically handled by the protocol stack, so to me it sounds strange that they would update information in the message itself.

(Filling in the max-age value can be handled by the protocol stack as well, which is a good idea at least for implementations that care about accuracy of that information, which is why it can be easy to update it in a retransmission.)

Grüße, Carsten