AS NZS 62676.2.1:2020 pdf download.Video surveillance systems for use in security applications Part 2.1: Video transmission protocols – General requirements (IEC 62676- 2-1:2013, MOD).
The following subclause specifies the detailed protocols to enable interoperability between VT devices in the digital VSS network. In addition, the VSS network environment requires supporting network infrastructure, such as access points, bridges, gateways, routers, and switches.
These non-normative devices are referred to in this standard as network infrastructure devices. IEC 62676-1-2 provides performance criteria for video network streaming and infrastructure devices to facilitate a good user experience and interoperability for video transmission devices.
4.2.2 Network streaming performance: quality of service
Video surveillance applications on IP networks benefit from high network performance and a good quality of service (Q0S) to optimize the way shared network resources are allocated among different surveillance applications, functions and devices.
All applications running on different video transmission devices have according to the nature of IP networks an equal opportunity to transmit data frames. Video surveillance is according to IEC 62676-1-2 sensitive to delay, latency variations and bandwidth reductions. By stream limitations or prioritized streaming IP video devices define how the video packets access network resources. In contrast to broadcasting applications with an unknown number of clients, IP video in security does not define any QoS protocol today. The QoS in a surveillance network is guaranteed by the proper setup and configuration at design time for a certain number of operators or receivers and by using the capabilities of a video management system (VMS) taking care of all video streaming and requests of the single video transmission devices. Requirements on the quality and performance on streaming are listed in
IEC 62676-1-2.
4.3 Device discovery and description
Device discovery and description enables a device on the VSS network to discover the presence and capabilities of the device itself and other devices on the network and collaborate with these devices in a uniform and consistent manner. ZeroConf and WSDiscovery address all of these needs and simplify device networking in the VSS network. For this reason device discovery and description is part of the IP solution for VT devices. Clause 10 specifies the detailed protocols to enable interoperability between VT devices in the digital VSS network. IEC 62676-1-2 specifies that under secure conditions devices cannot be automatically discovered; network security is then assured and addressed in IEC 62676-1-2.
4.4 Video media types and payload formats
Video formats describe how content is encoded and formatted for transport and final rendering on the VSS network. The video formats listed in IEC 62676-1-2 are intended to achieve a baseline for network interoperability while encouraging continued innovation in video codec technology.AS NZS 62676.2.1 pdf download.