2.2.8.1.1.1.1 Share Control Header (TS_SHARECONTROLHEADER)
The TS_SHARECONTROLHEADER header is a T.128 header ([T128] section 8.3) that MUST be present in the following PDUs.
Demand Active PDU (section 2.2.1.13.1).
Confirm Active PDU (section 2.2.1.13.2).
Deactivate All PDU (section 2.2.3.1).
Enhanced Security Server Redirection PDU (section 2.2.13.3.1).
All Data PDUs (section 2.2.8.1.1.1.2).
A definitive list of all Data PDUs is given in section 2.2.8.1.1.1.2 in the description of the pduType2 field.
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totalLength |
pduType |
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pduSource |
totalLength (2 bytes): A 16-bit unsigned integer. The total length of the packet in bytes (the length includes the size of the Share Control Header). If the totalLength field equals 0x8000, then the Share Control Header and any data that follows MAY be interpreted as a T.128 FlowPDU as described in [T128] section 8.5 (the ASN.1 structure definition is detailed in [T128] section 9.1) and MUST be ignored.
pduType (2 bytes): A 16-bit unsigned integer. It contains the PDU type and protocol version information. The format of the pduType field is described by the following bitmask diagram.
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0
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91
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92
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93
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1type
PDUVersion
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type (4 bits): A 4-bit unsigned integer that specifies the PDU type.
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Value (4 bits)
Meaning
PDUTYPE_DEMANDACTIVEPDU
0x1
Demand Active PDU (section 2.2.1.13.1).
PDUTYPE_CONFIRMACTIVEPDU
0x3
Confirm Active PDU (section 2.2.1.13.2).
PDUTYPE_DEACTIVATEALLPDU
0x6
Deactivate All PDU (section 2.2.3.1).
PDUTYPE_DATAPDU
0x7
Data PDU (actual type is revealed by the pduType2 field in the Share Data Header (section 2.2.8.1.1.1.2) structure).
PDUTYPE_SERVER_REDIR_PKT
0xA
Enhanced Security Server Redirection PDU (section 2.2.13.3.1).
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PDUVersion (12 bits): A 12-bit unsigned integer that specifies the PDU version.
pduSource (2 bytes): A 16-bit unsigned integer. The channel ID that is the transmission source of the PDU.