1
Scope
2 References
3 Definitions and conventions
4 Abbreviations and acronyms
5 Terminal capabilities
5.1 Audio capabilities
5.2 Video capabilities
5.3 Transfer rate
capabilities
5.4 Data capabilities
5.5 Terminals on
restricted networks: capability
5.6 Encryption and
extension-BAS capabilities
5.7 Null capability
6 Transmission
6.1 Transmission modes
6.2 Establishment of
compatible modes of operation
7 Frame structure
8 Basic sequences for in-channel
procedures
8.1 Capability exchange
sequence A
8.2 Mode switching
sequence B
8.3 Frame reinstatement
sequence C
9 Mode initialization, dynamic
mode switching and Mode 0 forcing
9.1 Mode initialization
procedure
9.2 Dynamic mode switching
(see Figure 2)
9.3 Mode 0 forcing
procedure
9.4 Mode mismatch recovery
procedure
9.5 Procedure for
influencing the mode transmitted from remote endpoint
10 Recovery from fault conditions
10.1 Unexpected loss of
synchronization or frame alignment
10.2 Recovery from loss of
connection(s)
11 Network consideration: call
connection, disconnection and call transfer
11.1 Call connection
11.2 Terminal disconnection
11.3 Call transfer
11.4 Conferencing
12 Procedure for activation and
de-activation of data channels
12.1 General
12.2 Procedures applicable
to all data types
12.3 Equipment capable of
operating using protocol according to Recommendation ITU‑T T.120
12.4 Data equipment not
conforming to Recommendation ITU-T T.120
12.5 Dummy data
13 Procedures for operation in
restricted networks
13.1 Network aspects
13.2 Terminal-network
configurations and properties
13.3 Transmission formats
13.4 Procedures
14 Procedure for use of
BAS-extension codes
15 Bit occupancy and the
sequencing of BAS codes
16 Procedure for dealing with
single/multiple channel interconnection
17 Procedure for use of encryption
control signal channel
18 Transmission of network
addresses
18.1 Address of initial
connection
18.2 Addresses of
additional connections
19 Informative codes
19.1 Recommendation version identification
19.2 Manufacturer/type
identification
Appendix I – Initialization: Case of videophone to
Recommendation ITU-T H.320, type Xb
Appendix II – Mode-0 forcing: Case of videophone to
Recommendation ITU-T H.320, type Xb
Appendix III – Example of use of message structure
III.1 Initial capability
exchange, including MBE-cap
III.2 Subsequent capability
exchange, including MBE capability message
III.3 Mode switch to non-standard
mode using MBE command
Appendix IV – Examples of symmetrical and asymmetrical
transmission modes
IV.1 Example of symmetrical
transmission mode
IV.2 Example of
asymmetrical transmission mode
IV.3 Example of
unsymmetrical video mode
Appendix V – Examples relating to data transmissions
V.1 Transfer-rate 1B,
audio at 48 kbit/s, no video or video off
V.2 Transfer-rate 1B,
audio at 16 kbit/s, no video or video off
V.3 Transfer-rate 1B,
audio at 16 kbit/s, video on
V.4 Transfer-rate 2B,
audio at 48 kbit/s, video on
V.5 Transfer-rate 2B,
audio at 16 kbit/s, video on
Appendix VI – Hierarchical capability BAS codes
Page
Appendix VII – Interpretation of received audio capability BAS codes
Appendix VIII – Examples of legal and illegal capability BAS
sequences
Appendix IX
Appendix X – An algorithm to determine whether an incoming bit
stream was encoded by m-law or A-law PCM
X.1 Basic determination
algorithm
X.2 Possible extensions
and refinements
Bibliography