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

[Christer Holmberg <[e-mail]>]

Hi,

    >>> 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.

...which means the recipient would miss any updated data conveyed in the retransmission.
    
    >>>> 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).

I think it is weird to define functionality that is based on the information being updated, and at the same time say that the sender can not rely that the receiver will see the updated information...
    
    >> 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.)

Yes, but in order for the updated information to be useful the recipient stack will also have to parse the information, and provide it to the recipient application.

The recipient can of course claim that the retransmission was lost, and that it never received it, but that's a hack :)

Regards,

Christer