While SIP does not actually contain the data itself, it was traditionally used hand-in-hand with the G.7xx audio codecs as well as Real-Time Transport Protocol
(RTP) or Real-Time Streaming Protocol (RTSP) to exchange actual audio, video, or other multimedia content between participants.
 [MS-RTPME] - v20160714 Real-Time Transport Protocol
(RTP/RTCP): Microsoft Extensions Copyright [c] 2016 Microsoft Corporation Release: July 14, 2016.
The real-time Transport Protocol
is a session level protocol defined by the IETF to provide transportation functions over networks that facilitate the delivery of data, like audio and video, in real time, using unicast or multicast techniques .
Real-time audio and video data are sent by using real-time transport Protocol
Norrman, "The secure real-time transport protocol
(SRTP)," Internet Engineering Task Force (IETF) 2004.
The user authentication function and the encode function, which use real-time transport protocol
(RTP), prevent improper access to the hotel network and the leak of user ID and password information, as well as protecting privacy of phone conversations.
Additionally, some firewalls are able to transcode unencrypted SIP and real-time transport protocol
(RTP) packets, translating them into transparent LAN service (TLS) and station RTP (SRTP) packets.
The agreement meant that Comtech EF Data would use Effnet's Compressed Real-time Transport Protocol
(CRTP) and IP Header Compression (IPHC) products to improve the efficiency of transmitting IP traffic over satellite links, Effnet said.
However, the Softswitch Consortium also promotes interoperability based on the Session Initiation Protocol (SIP), the Media Gateway Control Protocol (MGCP), and Real-time Transport Protocol
Real-time Transport Protocol
(RTP) (see Table III) was designed for real-time multiparticipant multimedia applications [Schulzrinne 1996; Schulzrinne et al.
Protocols affect lag time tremendously, with true streaming protocols such as real-time transport protocol
(RTP) and real-time messaging protocol (RTMP) being used for live streaming.
The proposed SeSIP comprises SIP, secure real-time transport protocol
(SRTP) , multimedia internet keying (MIKEY) , and a Diameter server  to provide VPN services in NEMO.