UNCW UNCW SIGGRAPH 2002 Topic #3: Continuous Media in Wired and Wireless Environments Ronald J. Vetter Department of Computer Science University of North Carolina at Wilmington

UNCW UNCW SIGGRAPH 2002 Outline of Presentation Protocols for Streaming Continuous Media Protocols for Streaming Continuous Media - RTP, RTSP, RSVP, SIP, HTTP, IP Multicast Quality of Network Issues Quality of Network Issues Mobile and Wireless Networks Mobile and Wireless Networks - Wireless LANs, MANs and WANs Conclusions Conclusions References References

UNCW UNCW SIGGRAPH 2002 Protocols for Streaming Continuous Media RTSP RTP HTTP RSVP SIP Continuous Media IP Multicast

UNCW UNCW SIGGRAPH 2002 Why not use HTTP? TCP delivery not always appropriate for continuous media TCP delivery not always appropriate for continuous media – No need for 100% reliability – Retransmission delay – Window backoff – N participants => N*N connections HTTP is stateless, media streams persist HTTP is stateless, media streams persist HTTP is hard to control (e.g., pause) and lacks appropriate flow control mechanisms HTTP is hard to control (e.g., pause) and lacks appropriate flow control mechanisms

UNCW UNCW SIGGRAPH 2002 Use a Toolbox Approach RTP for transport of audio/video/data with quality of service feedback RTP for transport of audio/video/data with quality of service feedback RTSP for the control of streams RTSP for the control of streams RSVP for reserving resources (when needed) RSVP for reserving resources (when needed) SIP for inviting participation SIP for inviting participation HTTP for retrieving media descriptions HTTP for retrieving media descriptions IP Multicast for control and data IP Multicast for control and data

UNCW UNCW SIGGRAPH 2002 Real-Time Transport Protocol (RTP) RTP provides end-to-end network transport functions suitable for applications transmitting real-time data, such as audio, video or simulation data, over multicast or unicast network services. RTP provides end-to-end network transport functions suitable for applications transmitting real-time data, such as audio, video or simulation data, over multicast or unicast network services. RTP does not address resource reservation and does not guarantee quality-of- service for real- time services. RTP does not address resource reservation and does not guarantee quality-of- service for real- time services. The data transport is augmented by a control protocol (RTCP) to allow monitoring of the data delivery in a manner scalable to large multicast networks, and to provide minimal control and identification functionality. The data transport is augmented by a control protocol (RTCP) to allow monitoring of the data delivery in a manner scalable to large multicast networks, and to provide minimal control and identification functionality.

UNCW UNCW SIGGRAPH 2002 Real Time Streaming Protocol (RTSP) RTSP is a client-server application-level protocol for controlling the delivery of data with real-time properties. RTSP is a client-server application-level protocol for controlling the delivery of data with real-time properties. It establishes and controls either a single or several time-synchronized streams of continuous media, such as audio and video. It establishes and controls either a single or several time-synchronized streams of continuous media, such as audio and video. It uses transport protocols such as UDP, multicast UDP, TCP, and RTP to deliver the continuous streams. It uses transport protocols such as UDP, multicast UDP, TCP, and RTP to deliver the continuous streams. RTSP acts as a "network remote control" for multimedia servers. Sources of data can include both live data feeds and stored clips. RTSP acts as a "network remote control" for multimedia servers. Sources of data can include both live data feeds and stored clips.

UNCW UNCW SIGGRAPH 2002 Resource Reservation Protocol (RSVP) RSVP is a resource reservation setup protocol designed for an integrated services Internet. RSVP is a resource reservation setup protocol designed for an integrated services Internet. RSVP provides receiver- initiated setup of resource reservations for multicast or unicast data flows, with good scaling and robustness properties. RSVP provides receiver- initiated setup of resource reservations for multicast or unicast data flows, with good scaling and robustness properties.

UNCW UNCW SIGGRAPH 2002 Session Initiation Protocol (SIP) SIP is an application-layer control (signaling) protocol for creating, modifying and terminating sessions with one or more participants. SIP is an application-layer control (signaling) protocol for creating, modifying and terminating sessions with one or more participants. These sessions include Internet multimedia conferences, Internet telephone calls and multimedia distribution. These sessions include Internet multimedia conferences, Internet telephone calls and multimedia distribution. Members in a session can communicate via multicast or via a mesh of unicast relations, or a combination of these. Members in a session can communicate via multicast or via a mesh of unicast relations, or a combination of these. SIP supports user mobility by proxying and redirecting requests to the user's current location. SIP supports user mobility by proxying and redirecting requests to the user's current location.

UNCW UNCW SIGGRAPH 2002 Internet Protocol (IP) Multicast IP multicast is a bandwidth-conserving technology that reduces traffic by simultaneously delivering a stream of information to multiple recipients. IP multicast is a bandwidth-conserving technology that reduces traffic by simultaneously delivering a stream of information to multiple recipients. Multicast addresses specify an arbitrary group of IP hosts that have joined the group and want to receive traffic sent to this group. Multicast addresses specify an arbitrary group of IP hosts that have joined the group and want to receive traffic sent to this group. IP multicast group addresses fall in the range of to IP multicast group addresses fall in the range of to

UNCW UNCW SIGGRAPH 2002 Basic Operations for Continuous Media

UNCW UNCW SIGGRAPH 2002 References RTP - RTP - RTSP - RTSP - RSVP - RSVP - SIP - SIP - HTTP - HTTP - IP Multicast - IP Multicast - Quality of Network – Ferner, C. and Vetter, R. (2002) An Integrated Framework for Implementing Quality of Network Concepts, Journal of Network and Systems Management, Vol. 10, No. 4. Quality of Network – Ferner, C. and Vetter, R. (2002) An Integrated Framework for Implementing Quality of Network Concepts, Journal of Network and Systems Management, Vol. 10, No. 4.