Axis Communications 210/211 MPEG-4 protocols and communication methods, How to stream MPEG-4?

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MPEG-4 protocols and communication methods

To deliver live streaming video over IP networks, various combinations of transport protocols and broadcast methods are employed.

RTP (Realtime Transport Protocol) is a protocol that allows programs to manage the real-time transmission of multimedia data, via unicast or multicast.

RTSP (Real Time Streaming Protocol) serves as a control protocol, to negotiate which transport protocol to use for the stream. RTSP is thus used by a viewing client to start a unicast session, see below.

UDP (User Datagram Protocol) is a communications protocol that offers limited service for exchanging data in a network that uses the Internet Protocol (IP). UDP is an alterna- tive to the Transmission Control Protocol (TCP). The advantage of UDP is that it is not required to deliver all data and may drop network packets when there is e.g. network congestion. This is suitable for live video, as there is no point in re-transmitting old information that will not be displayed anyway.

Unicasting is communication between a single sender and a single receiver over a net- work. This means that the video stream goes independently to each user, and each user gets their own stream. A benefit of unicasting is that if one stream fails, it only affects one user.

Multicast is bandwidth-conserving technology that reduces bandwidth usage by simul- taneously delivering a single stream of information to multiple network recipients. This technology is used primarily on delimited networks (intranets), as each user needs an uninterrupted data flow and should not rely on network routers.

How to stream MPEG-4?

Deciding on the combination of protocols and methods to use depends on your viewing requirements, and on the properties of your network.

RTP+RTSP

This method (actually RTP over UDP and RTSP over TCP) should be your first consideration for live video, especially when it is important to always have an up-to-date video stream, even if some images do get dropped. This can be configured as multicast or unicast.

Multicasting provides the most efficient usage of bandwidth, especially when there are large numbers of clients viewing simultaneously. Note however, that a multicast broadcast cannot pass a network router unless the router is configured to allow this. It is thus not possible to multicast over e.g. the Internet.

Unicasting should be used for video-on-demand broadcasting, so that there is no video traffic on the network until a client connects and requests the stream. However, if more and more unicast clients connect simultaneously, the AXIS 210/211 will at some point become overloaded. There is also a maximum of 20 simultaneous viewers to be considered.

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Contents Axis 210/211 Network Camera User’s Manual About this Document Contents Bandwidth Product Features Axis 211 Extra Features Power over Ethernet PoEDC-Iris Axis OverviewNetwork LED IndicatorsAccess From a Browser Accessing the CameraAccessing the cameras from the Internet Setting the PasswordAxis FocusingLive View Axis 210/211 Accessing the Camera Video Streams Stream TypesMotion Jpeg MPEG-4 protocols and communication methods How to stream MPEG-4?Other methods of accessing the video stream Axis Media ControlRTP/RTSP/HTTP or RTP/RTSP/HTTPS Other MPEG-4 clients Accessing the Setup tools ConfigurationImage Appearance Video and Image settingsTest Overlay SettingsOverlay Image Settings Video StreamOverlay image limitations Advanced Camera SettingsAdvanced MPEG-4 Settings Overlay image requirementsAxis Media Control Live View Config Customizing the defaultLayout Upload Own Web Files Example Check Show Custom Link User-defined LinksAction Buttons Output ButtonsHtml Examples Default Video Format in Internet Explorer for WindowsAMC Axis Media Control Settings Default Viewer for Motion JpegExternal Video Sequence ModeEvent Configuration Event ServersDefinitions Click Add triggered on the Event types Configuring Event TypesHow to set up a triggered event Triggered EventScheduled Event Pre-trigger and Post-trigger buffersMotion Detection History Sensitivity Port StatusSystem Options SecurityIP Address Filter Network Basic TCP/IP Settings IP Address ConfigurationDate & Time Host Name Configuration Network Advanced TCP/IP SettingsServices DNS ConfigurationSmtp email Link-Local AddressNetwork Traffic RTP multicast MPEG-4 LED SettingsMaintenance UPnPSupport ConfigurationResetting to the Factory Default Settings Using the Control ButtonAdvanced Pinout and Interface I/O Terminal ConnectorSchematic Diagram Terminal Connectors Upgrading the Firmware TroubleshootingSetup Basic Configuration Checking the FirmwareAxis Support Emergency Recovery ProcedureSymptoms, Possible Causes and Remedial Actions Video/Image problems, general Status and Network indicator LEDs are flashing red rapidly Video compression Technical SpecificationsPower over Ethernet Optimizing your system General performance considerationsBandwidth Frame rates Motion Jpeg and MPEG-4Glossary of Terms Switch see below AMC IndexSystem Options Overview