Technical Description of TANDBERG 8000 with software version E3/B8
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5.6
Maximum call length
Normally a call will stay up until it is disconnected by the user. The system has the ability to
automatically disconnect the call (incoming or outgoing) after a certain time.
Once a value (1-999 minutes; i.e. up to approximately 17 hours) is inserted in the menu this will
apply for all calls made. Default value is set to zero (i.e. max. call length
off
).
When the time has expired, the user will be prompted a ‘need for delay?’ message.
5.7
Closed Captioning/Text Chat
The TANDBERG system has the ability to display text on local and far end screens via the
system’s web page. Text chat is supported on both H.320 and H.323 and only in point-to-point
calls. The feature is implemented according to the ITU standard T.140.
T.140 defines a universal presentation-level protocol for text conversation which will work with
all multimedia protocols and with the existing standard for text telephony; V.18. This is
expected to greatly improve the lives of those users reliant on text-based conversation systems,
such as the hearing and speech impaired.
Please, see the User Manual for more information about the usage of this feature.
5.8
Other Standards supported
5.8.1
H.320
This ITU standard is a generic name applied to all standards based videoconferencing
equipment. By its nature it calls up a number of other standards that are designed to perform a
set process to enable the transmission of video, audio and data (i.e. multimedia) across any
synchronous network.
5.8.2
H.323
H.323 is an ITU standard that specifies the operation of real-time audio, video and data
communications over packet based networks. These networks are collectively termed IP
networks and are by nature asynchronous.
5.8.3
H.331 (Broadcast mode)
The TANDBERG system supports the ITU standard H.331 which may be used in special
networks where cost of bandwidth is of great importance, such as Satellite networks.
H.331 provides a broadcast mode where one codec sends only and one (or many) codecs receive
only- thus, no handshaking is done between the codecs.
An essential technical feature in H.331 is that communication channels cannot be two-way
between the information providing terminal and any information receiving terminal because the
path from the receiving terminal to the transmitting one is terminated at the exchange.
H.331 is separate from, but based on H.320 and caters for particular needs of the broadcasting
type multipoint system so that terminals operating for both H.320 and H.331 are easily
implemented.
