Re: Decentralized reliable instant messaging?

[Stefan Monnier <monnier@iro.umontreal.ca>]

>> "shocked that anyone would want to design or use an
>>                 unreliable messaging system"
> Email is getting less and less reliable, so have you given up using it?? :-(

There's unreliable and there's unreliable.

In the XMPP world, the basic protocol will just send the message to the
destination over the existing TCP connection and won't care to check
for some kind of acknowledgment that the message was received.

In theory, the server could react to a TCP disconnect, but that won't
tell it which part of the stream was received and which wasn't, so in
practice, XMPP servers don't even care to check for a TCP disconnect
error in order to detect a possible message loss.

For SIP, in my experience, if I'm not connected when an SIP message comes
in, the SIP server just drops the message silently.


        Stefan