Upaya wrote:
Hi Paul,

Do you suggest that I should send some sort of hidden
INVITE at the beginning of the message session to
establish a dialog?

Yes, that is the intent with message sessions. Whether it is hidden, or visible as it is with a phone call, is entirely a function of the endpoint implementation.


The challenge that is as yet unaddressed is how to decide when to use page mode messaging, and when to use session mode messaging - especially if you want this all hidden from the UI.

Paul

Thanks,

Wendy

--- Paul Kyzivat <[EMAIL PROTECTED]> wrote:

Upaya,

This is one of the reasons we are working on
session-mode IM. Use of the MESSAGE message is page-mode IM. In page mode, there
is no session, so in general the proxy will be involved in routing
each message. And if the target has multiple UASs then each message may
be forked. Responses are a bit of an issue as well - in general the best
you can do is address a response to the From address in the
request.


Technically you can send MESSAGE messages within a
dialog and so guarantee a consistent pair of endpoints are
interacting, and generally cut the proxy out as well. (I believe this is what
MS does.) But that is not recommended behavior. And because MESSAGE is not
dialog establishing you need to do something else to establish the
dialog, such as send a media-less invite.


While not yet complete, the direction we are
pursuing for session oriented IM is to send an invite with an offer for a
message-session media stream. And then send the IMs via that stream
rather than via MESSAGE messages. The protocol for this is still in
progress, with the working name of MSRP. (Message Session Relay
Protocol.)


Paul

Upaya wrote:

Thank you and Smith for the reply on my previous
message.

I have a question regarding an IM conversation.
Similar to MSN Messenger and Yahoo Messenger,

users


can exchange messages in one session/window.

For example: A Short Conversation



John wrote: Hi Mary!
Mary wrote: Hello John
John wrote: How are you?


Based on RFC3428, John sends the first message to

the


proxy server, then the proxy server forwards the
message to Mary.

What about the second and the third message? Does

it


still need the proxy server to perform lookup and
forward?  Also, all three messages above should be

in


the same session, right?

Thanks,

Wendy



__________________________________
Do you Yahoo!?
Yahoo! Search - Find what you&#25262;e looking for

faster


http://search.yahoo.com
_______________________________________________
Sip-implementors mailing list
[EMAIL PROTECTED]


http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors



__________________________________
Do you Yahoo!?
Yahoo! Finance Tax Center - File online. File on time.
http://taxes.yahoo.com/filing.html
_______________________________________________
Sip-implementors mailing list
[EMAIL PROTECTED]
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors


_______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors

Reply via email to