Re: [bfcpbis] Alexey Melnikov's Discuss on draft-ietf-bfcpbis-sdp-ws-uri-08: (with DISCUSS and COMMENT)

["Ram Mohan R (rmohanr)" <[e-mail]>]

Hi Alexey,

-----Original Message-----
From: Alexey Melnikov <[e-mail]>
Date: Monday, 16 January 2017 at 8:25 PM
To: "Ram Mohan R (rmohanr)" <[e-mail]>, The IESG <[e-mail]>
Cc: "[e-mail]" <[e-mail]>, "[e-mail]" <[e-mail]>, "Charles Eckel (eckelcu)" <[e-mail]>, "[e-mail]" <[e-mail]>
Subject: Re: [bfcpbis] Alexey Melnikov's Discuss on draft-ietf-bfcpbis-sdp-ws-uri-08: (with DISCUSS and COMMENT)

    Hi Ram,
    
    On Mon, Jan 16, 2017, at 02:49 PM, Ram Mohan R (rmohanr) wrote:
    > Hi Alexey,
    > 
    > Please see inline <Ram>
    > 
    > -----Original Message-----
    > From: Alexey Melnikov <[e-mail]>
    > Date: Monday, 16 January 2017 at 7:57 PM
    > To: "Ram Mohan R (rmohanr)" <[e-mail]>, The IESG <[e-mail]>
    > Cc: "[e-mail]"
    > <[e-mail]>, "[e-mail]"
    > <[e-mail]>, "Charles Eckel (eckelcu)" <[e-mail]>,
    > "[e-mail]" <[e-mail]>
    > Subject: Re: [bfcpbis] Alexey Melnikov's Discuss on
    > draft-ietf-bfcpbis-sdp-ws-uri-08: (with DISCUSS and COMMENT)
    > 
    >     Hi Ram,
    >     
    >     On Mon, Jan 16, 2017, at 06:09 AM, Ram Mohan R (rmohanr) wrote:
    >     > Hi Alexey,
    >     > 
    >     > Thanks for your feedback. Please see inline <Ram>
    >     > 
    >     > -----Original Message-----
    >     > From: bfcpbis <[e-mail]> on behalf of Alexey Melnikov
    >     > <[e-mail]>
    >     > Date: Saturday, 14 January 2017 at 3:49 AM
    >     > To: The IESG <[e-mail]>
    >     > Cc: "[e-mail]"
    >     > <[e-mail]>, "[e-mail]"
    >     > <[e-mail]>, "Charles Eckel (eckelcu)" <[e-mail]>,
    >     > "[e-mail]" <[e-mail]>
    >     > Subject: [bfcpbis] Alexey Melnikov's Discuss on
    >     > draft-ietf-bfcpbis-sdp-ws-uri-08: (with DISCUSS and COMMENT)
    >     > 
    >     >     Alexey Melnikov has entered the following ballot position for
    >     >     draft-ietf-bfcpbis-sdp-ws-uri-08: Discuss
    >     >     
    >     
    >     >     ----------------------------------------------------------------------
    >     >     DISCUSS:
    >     >     ----------------------------------------------------------------------
    >     >     
    >     >     This is generally a well written document, but I have a small list of
    >     >     issues that I would like to discuss before recommending its approval:
    >     >     
    >     >     1) Are a=ws-uri and a=wss-uri mutually exclusive? (Section 4.3 is a
    >     >     good
    >     >     place to mention what to do if both are specified).
    >     > 
    >     > <Ram> Yes kind of. In a given media line (m= line) we will either have
    >     > a=ws-uri or a=wss-uri. That said a response from a BFCP server using
    >     > webSocket as a transport can
    >     > have two media lines one with ws and other with wss. Something like:
    >     > 
    >     > Answer (server):
    >     >    m=application 50000 TCP/WSS/BFCP *
    >     >    a=setup:passive
    >     >    a=connection:new
    >     >    a=wss-uri:wss://bfcp-ws.example.com?token=3170449312
    >     >    m=application 50000 TCP/WS/BFCP *
    >     >    a=setup:passive
    >     >    a=connection:new
    >     >    a=ws-uri:ws://bfcp-ws.example.com?token=3170449312
    >     
    >     [Alexey]: This is exactly my problem, you should specify how a
    >     recipient
    >     should handle your example above. If you only have 1 attribute, the
    >     problem goes away entirely.
    > 
    > <Ram> in the above case, they are still two different m= lines. The
    > receiver (after offer/answer is done) of this SDP connects to the URI
    > mentioned in that m= line. 
    > Note I just re-used the same URL/port in the example above. If there are
    > multiple m=application media lines (they will be for different
    > applications) being negotiated in SDP, one application may use secure WS
    > and other application may use non-secure WS. The client after it receives
    > the answer SDP will just setup the connection to the URI specified in the
    > attribute.  
    
    Sorry, I was thinking about different example:
    
    m=application 50000 TCP/WSS/BFCP *
       a=setup:passive
       a=connection:new
       a=wss-uri:wss://bfcp-ws.example.com?token=3170449312
       a=ws-uri:ws://bfcp-ws.example.com?token=3170449312
    
    You have 2 conflicting URIs for the same m= line. Is this possible?

<Ram> No this is not possible. If the transport is TCP/WSS/BFCP we should have only a=wss-uri. If transport is TCP/WS/BFCP we should have only a=ws-uri.

Regards,
  Ram

    > I don’t see any problem in here.  
    > 
    > Regards,
    > Ram
    > 
    >     >     Why not a single attribute, considering that both ws: and wss: URIs
    >     >     are
    >     >     possible?
    >     > 
    >     > <Ram> I would still prefer two attributes. We just followed the
    >     > convention / approach that was used in [RFC6455].  
    >     
    >