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RFCs & Standards Voice over IP

DTMF over IP – SIP INFO, Inband & RTP Events

DTMF’s implementation in VoIP and the 3 types of DTMF encoding (Inband, RTP Event and SIP INFO)

Categories
RFCs & Standards Voice over IP

RFC2976 / RFC6086 – SIP INFO

SIP INFO was designed to carry session related information during a session. SIP was designed to setup and tear down sessions, with little thought given to what happens after the setup, but before the teardown. SIP INFO (RFC2976) was designed to fill this gap. (Obsoleted by RFC6086) It’s predominantly used now to carry DTMF info […]

Categories
RFCs & Standards Voice over IP

RFC2833 – RTP Events

RFC2833 was designed to carry DTMF signalling, other tone signals and telephony events in RTP packets. This was later superseded by RFC4733, but everyone still referrers to this protocol as RFC2833, so I will too. RFC2833 a special RTP payload designed to carry DTMF signalling information, so it operates on the same source / destination […]