Subject: [MMUSIC] Registry for candidate attributes extensions

From: Roman Shpount <[email-masked]>
Date: Fri, 20 Apr 2018 14:44:51 -0400

Hi All,

Section 4.1 of ice-sip-sdp defines extension attributes for ICE candidates:

candidate-attribute   = "candidate" ":" foundation SP component-id SP
                        transport SP
                        priority SP
                        connection-address SP     ;from RFC 4566
<https://tools.ietf.org/html/rfc4566>
                        port         ;port from RFC 4566
<https://tools.ietf.org/html/rfc4566>
                        SP cand-type
                        [SP rel-addr]
                        [SP rel-port]
                        *(SP extension-att-name SP
                                extension-att-value)

extension-att-name    = token
extension-att-value   = *VCHAR

There is surprising little written about these extension attributes. Should
there be a requirement that these attributes must be defined in RFC and
that IANA registry for this attributes should be created?

Only attribute like this I saw in the wild is "generation". For example:

a=candidate:750991856 1 udp 25108223 237.30.30.30 58779 typ relay raddr
47.61.61.61 rport 54761 generation 0

This attribute is widely used, but I do not think this attribute is
actually defined anywhere.

Regards,
_____________
Roman Shpount