What are the audio and video network transmission protocols? The characteristics between RTSP/RTMP/SRT/NDI protocols

What are the network video transmission protocols? The characteristics between RTSP/RTMP/SRT/RTP are described in detail below:

RTP protocol (Real-time Transport Protocol) is a network transmission protocol, is a real-time transmission protocol technology, RTP protocol is often used in streaming media system (with RTSP protocol) video conference and Push to Talk system (with H .323 or SIP), making it the technical foundation of the IP telephony industry. The RTP real-time transmission protocol provides end-to-end transmission services with real-time characteristics for data, such as interactive video audio or analog data under multicast or unicast network services.

The RTSP protocol is the earliest video transmission protocol. RTSP is a real-time streaming protocol. It is an application layer protocol in the TCP/IP protocol system. RTSP defines how one-to-many applications can efficiently transmit multimedia data through an IP network. RTSP is located above RTP and RTCP in architecture. It uses TCP or UDP to complete data transmission.

RTSP also provides an extensible framework that enables real-time data, such as audio and video, to be controlled on demand. Data sources include live data and data stored in clips. The advantage of RTSP protocol is that it can control the video frame, so it can carry applications with high real-time performance.

The RTMP protocol is a (Real Time Messaging Protocol) real-time message transmission protocol, which is based on TCP and is a protocol family, including RTMP basic protocol and RTMPT/RTMPS/RTMPE and other variants. RTMP is a network protocol designed for real-time data communication. It is mainly used for audio, video, and data communication between the Flash/AIR platform and the streaming/interaction server that supports the RTMP protocol.

RTMP is an open protocol developed for the transmission of audio, video, and data between Flash players and servers.

The RTMP protocol is like a container for data packets. These data can be either AMF format data or video/audio data in FLV. A single connection can transmit multiple network streams through different channels. The packets in these channels are transmitted according to fixed-size packets.

HLS protocol (HTTP Live Streaming) is Apple's dynamic bit rate adaptation technology, which is mainly used for audio and video services of PCs and Apple terminals. HLS protocol's small slicing method will generate a large number of files, and storing or processing these files will cause a lot of waste of resources.

If you want to achieve a time shift of several days, the index volume will be a huge number, and it will obviously affect the request speed. Therefore, the HLS protocol is quite demanding on storage I/O. HLS only requests basic HTTP messages. Unlike Real-time Transport Protocol (RTP), HLS can pass through any firewall or proxy server that allows HTTP data to pass through. It is also easy to use content distribution networks to transmit media streams.

The SRT protocol is the abbreviation of (Secure Reliable Transport). SRT was jointly established by Haivision and Wowza. It manages and supports the open source application of the SRT protocol. This organization is committed to promoting the interoperability of video streaming solutions and promoting the pioneering collaboration of the video industry to achieve low-latency network video transmission.

SRT allows direct connection between the signal source and the target. This is in stark contrast to many existing video transmission systems, which require a centralized server to collect signals from remote locations and redirect them to one or Multiple destinations. The central server-based architecture has a single point of failure, which can also become a bottleneck during periods of high traffic. Transmitting signals through a hub also increases the end-to-end signal transmission time and may double the bandwidth cost because two links need to be implemented: one from the source to the central hub, and the other from the center to the destination. By using a direct connection from source to destination, SRT can reduce latency, eliminate central bottlenecks, and reduce network costs. The SRT protocol has been extended and customized on the basis of UDT, and has network transmission packet loss detection/delay control/video encryption functions.

NDI (Network Device Interface) is an IP network device interface protocol. It is a standard protocol for ultra-low latency, lossless transmission, and interactive control through an IP network; an open protocol that enables video-compatible products to share video through a local area network is a standard for ultra-low latency, lossless transmission, and interactive control through an IP network protocol.

NDI is an open protocol that enables video-compatible products to share video through a local area network. NDI transmission will be more cost-effective, more stable, and more resistant to interference than coaxial cable transmission. NDI can transmit and receive multiple broadcast-quality signals through the IP network in real time, and has the characteristics of low delay, accurate frame video, and mutual recognition and communication of data streams. NDI supports an access mechanism that allows manual input of the IP addresses of computers on other subnets that are running NDI sources.