Category : VOIP

Session Description Protocol Delayed Offer

I wrote a few days ago about Media Formats and priorities within Session Description Protocol (SDP) payload. Something that occasionally comes up is the ability to delay the SDP information so that it is not contained within the INVITE message. This is known as Delayed Offer. In this scenario, the originator sends an INVITE message

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Media Formats within Session Description Protocol

I was asked a question recently on SIP codec negotiation between voice devices where the devices can support multiple codecs and how this is accomplished during call setup. The Session Description Protocol (SDP) is used within the SIP message bodies to agree session information and announces Media Formats that the originating device will support for

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