GRASS VALLEY IQUCP25, Руководство пользователя

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Getting Started with the Multiviewer
IP Routing Terminology
IP Routing Terminology
Video Input One of 12 video inputs to the Multiviewer SDC.
Multiviewer Input One of 12 video inputs to the multiviewer block within the
Multiviewer SDC.
Term Definition
Term Definition
Control network Typically an Ethernet network dedicated for device control.
COTS Commercial Off-The-Shelf. Refers to hardware that is not specific to an
industry, but is generic and readily available.
In this case, it is high-performance IT switching equipment,.
Destination Receiver of one or more flows. Destination spigot.
Essence A general term used to describe a component of a media signal.
Video, Audio and Metadata are all essences.
Fabric Term for the networks that can make up a redundant network system,
Fabric “A” and Fabric “B”.
FEC Forward Error Correction.
A technique for controlling errors in data transmission where the
sender encodes message in a redundant way by using an error-
correcting code. The redundancy allows the receiver to detect and
correct errors.
Flow Another term for an elementary IP stream, usually a sequence of real-
time data sent as an RTP IP data stream.
For example,
TR-03 describes how a media stream (e.g. an original SDI stream) may
be sent as three flows: Video, Audio and Ancillary essence data.
IEEE 1588 A Precision Time Protocol (PTP) to synchronize distributed clocks to
within 1 microsecond through Ethernet networks.
PTP runs on IP networks, transferring precision time to slave devices
through a 1 GHz virtual clock (time base). It is used to synchronize TR-
03 elementary streams.
IGMPv3 Internet Group Management Protocol.
Communications protocol used in IP multicasting by client IP devices
and an IP router to establish multicast group membership.
The routing function of a traditional video router can be replicated
with a IP Network Router Controller deice and a COTS IP Switch which
supports the IGMPv3 protocol.
In-Band Control Sending control messages for an IP routing system in the media IP
network fabric.
IP Stream Real-time data (for example, video and/or audio) sent over a network.