Re: [sipcore] Websocket is a new transport or new URI?

["Ravindran, Parthasarathi" <[e-mail]>]

Hi Christer,

When I argued for new URI, the contact shall use new URI with 
the existing TCP transport like

   sipws:[e-mail];transport=tcp

"sipws" URI shall be compare with "ws" URI in Websocket protocol 
(Sec 3 of RFC 6455). 

Thanks
Partha

>-----Original Message-----
>From: Christer Holmberg [mailto:[e-mail]]
>Sent: Thursday, April 26, 2012 1:48 AM
>To: Iñaki Baz Castillo; Ravindran, Parthasarathi
>Cc: [e-mail]
>Subject: RE: [sipcore] Websocket is a new transport or new URI?
>
>Hi,
>
>I agree with Inaki.
>
>Whatever "layer" we consider the WebSocket to be, in my opinion the URI
>scheme is used for addressing (either as an AOR or a contact), and
>should be independent of the transport.
>
>For what would the new scheme be needed  anyway?
>
>Regards,
>
>Christer
>
>
>
>
>________________________________________
>From: [e-mail] [[e-mail]] On Behalf Of
>Iñaki Baz Castillo [[e-mail]]
>Sent: Wednesday, April 25, 2012 8:25 PM
>To: Ravindran, Parthasarathi
>Cc: [e-mail]
>Subject: Re: [sipcore] Websocket is a new transport or new URI?
>
>Hi Partha,
>
>
>2012/4/25 Ravindran, Parthasarathi <[e-mail]>:
>> So IMO, it is more appropriate to define new URI scheme like SIPWS
>> rather than defining websocket as a transport.
>
>
>The SIP transport defined by this draft is WebSocket, instead of TCP.
>WebSocket (RFC 6455) is defined to work on top of TCP but, even if a
>future spec defines WebSocket to run over SCTP, the SIP transport would
>still be "WebSocket" (or perhaps "WebSocket-SCTP" but that something in
>which I won't waste time now given the fact that RFC 6455
>*mandates* TCP layer-3 transport and does not leave the door open for
>other layer-3 transports).
>
>WebSocket is, indeed, a layer on top of a network transport (layer 3)
>but it's designed to work as a *transport* layer since it defines a
>framing mechanism to send application messages and control mesages in
>both directions. Applications (i.e. JavaScript scripts, PHP/Java web
>apps) use WebSocket as a transport layer.
>
>You can find lot of cases in which a transport runs on top of other
>transports. For example, in the recent IETF #83 the RTCWEB WG approved
>(or discussed) SCTP-over-DTLS-over-ICE-over-UDP as the transport for the
>WebRTC Data-Channel mechanism. A "transport" does not necessarily mean
>"layer 3 network transport".
>
>
>
>About SIPS, the last S in SIPS stands for "secure" regardless of the
>undelying SIP transport used. AFAIK it does not necessarily mean "TLS".
>Take for example draft-jennings-sip-dtls-05 [1] which defines SIP over
>DTLS over UDP. The draf is expired, but anyhow, it defines a secure SIP
>transport which does not use TLS but DTLS (which is similar but NOT the
>same). The draft also allows SIPS messages through DTLS over UDP.
>
>[1] http://tools.ietf.org/html/draft-jennings-sip-dtls-05
>
>
>When a SIPS message is carried on top of a secure WebSocket connection
>(which means SIP over WebSocket over TLS over TCP) the security level is
>basically the same as if it was SIP over TLS over TCP. Therefore I
>consider that a secure WebSocket connection fits the requirements of the
>SIPS mechanism, thus secure WebSocket should be considered as a secure
>SIP transport.
>
>
>
>About the SIPWS and SIPWSS schemas you propose, don't take me wrong but
>I consider that the worst possible idea. First of all because I don't
>agree with your rationale (I insist that, from the point of view of a
>SIP stack, WebSocket is the ***SIP transport***, instead of TCP).
>Secondly, because adding new URI schemas would just break the existing
>SIP world (there are still some SIP entities that don't understand SIPS
>schema and you are proposing two new ones?).
>
>
>Thanks a lot for your comments.
>
>
>--
>Iñaki Baz Castillo
><[e-mail]>
>_______________________________________________
>sipcore mailing list
>[e-mail]
>https://www.ietf.org/mailman/listinfo/sipcore