"Potential problems with codecs negotiation using SDP protocol"@en . . "Codec negotiation; RFC 3555; SDP; G.729"@en . "RIV/60162694:G43__/13:00492667" . "2013-01-01+01:00"^^ . . "6"^^ . . . . . "I" . . "International Conference on Military Technologies 2013, ICMT'13" . "G43" . . . "University of Defence, Brno, 2013" . . . "[8C1FE765BAB5]" . . "Potential problems with codecs negotiation using SDP protocol" . . "97842" . . "2"^^ . "Modern voice communication networks are usually built as converged networks enabling voice and data transfer upon using an Internet Protocol (IP). Voice services further require a signalling protocol for their work. Nowadays, the Session Initiation Protocol (SIP) is the most popular signalling protocol used in these types of networks. Compared to traditional telephone networks, voice communication over the IP protocol enables a choice of a codec. The codec that will be used to communicate is negotiated by terminals or gateways using the Session Description Protocol (SDP). It is transmitted in the body of the SIP protocol. If respected the rule that each communicating device must support the G.711 codec, it should not lead to a situation where the communicating parties cannot agree on the codec. In practice, the situation is quite different. In many cases, it is not possible to establish voice communications because of unsuccessful negotiation of the codec. The following article briefly presents basic features of the G.729 codec, the SDP according to RFC 4566 and presents one example of unsuccessful codec negotiation obtained in experiments with VoIP equipment, especially equipment used in the ACR." . "Modern voice communication networks are usually built as converged networks enabling voice and data transfer upon using an Internet Protocol (IP). Voice services further require a signalling protocol for their work. Nowadays, the Session Initiation Protocol (SIP) is the most popular signalling protocol used in these types of networks. Compared to traditional telephone networks, voice communication over the IP protocol enables a choice of a codec. The codec that will be used to communicate is negotiated by terminals or gateways using the Session Description Protocol (SDP). It is transmitted in the body of the SIP protocol. If respected the rule that each communicating device must support the G.711 codec, it should not lead to a situation where the communicating parties cannot agree on the codec. In practice, the situation is quite different. In many cases, it is not possible to establish voice communications because of unsuccessful negotiation of the codec. The following article briefly presents basic features of the G.729 codec, the SDP according to RFC 4566 and presents one example of unsuccessful codec negotiation obtained in experiments with VoIP equipment, especially equipment used in the ACR."@en . "Brno" . "Brno" . . "2"^^ . "978-80-7231-917-6" . "http://vavtest.unob.cz/registr" . "Maz\u00E1lek, Anton\u00EDn" . "RIV/60162694:G43__/13:00492667!RIV14-MO0-G43_____" . "Vr\u00E1nov\u00E1, Zuzana" . . . "Potential problems with codecs negotiation using SDP protocol"@en . "Potential problems with codecs negotiation using SDP protocol" .