Avaya Equinox Manual page 88

Glossary
H.239
H.243
H.245
H.261
H.263
H.264
H.264 Baseline
Profile
H.264 High Profile
H.320
H.323
August 2017
H.239 is a widespread protocol used with H.323 endpoints, to define the
additional media channel for data sharing (like presentations) alongside the
videoconference, and ensures only one presenter at a time.
H.243 is the protocol used with H.323 endpoints enabling them to remotely
manage a videoconference.
H.245 is the protocol used to negotiate call parameters between endpoints,
and can control a remote endpoint from your local endpoint. It is part of the
H.323 set of protocols.
H.261 is an older protocol used to compress CIF and QCIF video
resolutions. This protocol is not supported by the XT Series.
H.263 is an older a protocol used to compress video. It is an enhancement
to the H.261 protocol.
H.264 is a widespread protocol used with SIP and H.323 endpoints, which
defines video compression. Compression algorithms include 4x4 transforms
and a basic motion comparison algorithm called P-slices. There are several
profiles within H.264. The default profile is the H.264 Baseline Profile, but
H.264 High Profile uses more sophisticated compression techniques.
See H.264 on page 88.
H.264 High Profile is a standard for compressing video by up to 25% over
the H.264 Baseline Profile, enabling high definition calls to be held over
lower call speeds. It requires both sides of the transmission (sending and
receiving endpoints) to support this protocol. H.264 High Profile uses
compression algorithms like:
• CABAC compression (Context-Based Adaptive Binary Arithmetic
Coding)
• 8x8 transforms which more effectively compress images containing
areas of high correlation
These compression algorithms demand higher computation requirements,
which are offered with the dedicated hardware available in Equinox Solution
components. Using H.264 High Profile in videoconferencing requires that
both the sender and receiver's endpoints support it. This is different from
SVC which is an adaptive technology working to improve quality even when
only one side supports the standard.
H.320 is a protocol for defining videoconferencing over ISDN networks.
H.323 is a widespread set of protocols governing the communication
between endpoints in videoconferences and point-to-point calls. It defines
the call signaling, control, media flow, and bandwidth regulation.
Installing the Avaya Equinox Streaming and Recording Server
Comments on this document? infodev@avaya.com
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