Protocol: ITU-Q931 Information Elements

ITU-Q931 Information Elements

Codeset 0

Q931: IE Segmented Message (SM 0/00)

- Octet 1:	IE type
bits 8-1	00 H
- Octet 3:	mandatory
bit 8	First segment indicator
bits 7-1	Number of segment remaining
- Octet 4:	mandatory
bits 7-1	Segmented message type

IE Field: First segment indicator (SM)

bit 8	First segment indicator
0	Subsequent segment to first segment
1	First segment of segmented message

Q931: IE Bearer Capability (BC 0/04)

- Octet 1:	IE type
bits 8-1	04 H
- Octet 3:	mandatory
bits 7-6	Coding standard
bits 5-1	Information transfer capability
- Octet 4:	mandatory
bits 7-6	Transfer mode
bits 5-1	Information transfer rate
- Octet 4a:	optional
bits 7-5	Structure
bits 4-3	Configuration
bits 2-1	Establishment
- Octet 4b:	optional
bits 7-6	Symmetry
bits 5-1	Information transfer rate
- Octet 5:	optional
bits 7-6	0 1
bits 5-1	User information layer 1 protocol The contents of this field depends on the national implementation: ETSI British-Telecom ISDN2 protocol
- Octet 5a:	optional
bit 7	Synchronous/asynchronous
bit 6	Negotiation
bits 5-1	User rate
- Octet 5b:	optional (V110/X30 in octet 5)
bits 7-6	Intermediate rate
bit 5	Network independent clock on Tx
bit 4	Network independent clock on Rx
bit 3	Flow control on Tx
bit 2	Flow control on Rx
- Octet 5b:	optional (V120 in octet 5)
bit 7	Rate adaption header
bit 6	Multiple frame
bit 5	Mode of operation
bit 4	LLI negotiation
bit 3	Assignor/assignee
bit 2	In-band/out-band negociation
- Octet 5c:	optional
bits 7-6	Number of stop bits
bits 5-4	Number of data bits
bits 3-1	Parity
- Octet 5d:	optional
bit 7	Duplex mode
bits 6-1	Modem type
- Octet 6:	optional
bits 5-1	User information layer 2 protocol
- Octet 7:	optional
bits 5-1	User information layer 3 protocol

Maximum length (including octet 1 and 2): 13 octets

IE Field: Coding standard (BC)

bits 7-6	Coding standard.
0 0	CCITT standardized coding
0 1	Reserved
1 0	National standard
1 1	Standard defined for the network

IE Field: Information transfer capab. (BC)

bits 5 _ _ _ 1	Information transfer capability
0 0 0 0 0	Speech
0 1 0 0 0	Unrestricted digital information
0 1 0 0 1	Restricted digital information
1 0 0 0 0	3,1 kHz audio
1 0 0 0 1	7 kHz audio
1 1 0 0 0	Video

IE Field: Transfer mode (BC)

bits 7-6	Transfer mode
0 0	Circuit mode
1 0	Packet mode

IE Field: Information transfer rate (BC)

bits 5 _ _ _ 1	Information transfer rate
0 0 0 0 0	Packet mode code used for the calls in packet mode
1 0 0 0 0	64 kbit/s Circuit mode
1 0 0 0 1	2 x 64 kbit/s Circuit mode
1 0 0 1 1	384 kbit/s Circuit mode
1 0 1 0 1	1536 kbit/s Circuit mode
1 0 1 1 1	1920 kbit/s Circuit mode

IE Field: Structure (BC)

bits 7 6 5	Structure
0 0 0	Default
0 0 1	8kHz integrity
1 0 0	Service data unit integrity
1 1 1	Unstructured

IE Field: Configuration (BC)

bits 4 3	Configuration
0 0	Point-to-point

IE Field: Establishment (BC)

bits 2 1	Establishment
0 0	Demand

IE Field: Symmetry (BC)

bits 7 6	Establishment
0 0	Bidirectional symmetric

IE Field: User information layer 1 prot.
- ETSI protocol (BC)

bits 5 _ _ _ 1	User information layer 1 protocol
0 0 0 0 1	Rate adaptation V110/X30
0 0 0 1 0	Recommendation G711 µ-law
0 0 0 1 1	Recommendation G711 A-law
0 0 1 0 0	Recommendation G721 32 kbit/s
0 0 1 0 1	Recommendation G722-G725 7 KHz audio :
0 0 1 1 0	Recommendation G7xx 384 kbit/s video
0 0 1 1 1	Non-CCITT rate adaptation
0 1 0 0 0	Rate adaptation V120
0 1 0 0 1	Rate adaptation X31

IE Field: User information layer 1 prot.
- British-Telecom ISDN2 protocol (BC)

bits 5 _ _ _ 1	User information layer 1 protocol
0 0 0 0 0	Recommendation I412
0 0 0 0 1	Rate adaptation V110/X30
0 0 0 1 0	Recommendation G711 µ-law
0 0 0 1 1	Recommendation G711 A-law
0 0 1 0 0	Recommendation G721 32 kbit/s
0 0 1 0 1	Recommendation G722-G725 7 KHz audio
0 0 1 1 0	Recommendation G7xx 384 kbit/s video
0 0 1 1 1	Non-CCITT rate adaptation
0 1 0 0 0	Rate adaptation V120
0 1 0 0 1	Rate adaptation X31

IE Field: Synchronous/asynch. (BC)

bit 7	Synchronous/asynchronous
0	Synchronous
1	Asynchronous

IE Field: Negotiation (BC)

bit 6	Negotiation
0	Negotiation in the band not possible.
1	Negotiation in the band possible.

IE Field: User rate (BC)

bits 5 _ _ _ 1	User rate
0 0 0 0 0	E-bits rec I460
0 0 0 0 1	0.6 kbit/s Recommendations V6 and X1.
0 0 0 1 0	1.2 kbit/s Recommendation V6.
0 0 0 1 1	2.4 kbit/s Recommendations V6 and X1.
0 0 1 0 0	3.6 kbit/s Recommendation V6.
0 0 1 0 1	4.8 kbit/s Recommendations V6 and X1.
0 0 1 1 0	7.2 kbit/s Recommendation V6.
0 0 1 1 1	8 kbit/s Recommendation I460.
0 1 0 0 0	9.6 kbit/s Recommendations V6 and X1.
0 1 0 0 1	14.4 kbit/s Recommendation V6.
0 1 0 1 0	16 kbit/s Recommendation I460.
0 1 0 1 1	19.2 kbit/s Recommendation V6.
0 1 1 0 0	32 kbit/s Recommendation I460.
0 1 1 1 0	48 kbit/s Recommendation V6 and X1.
0 1 1 1 1	56 kbit/s Recommendation V6.
1 0 0 0 0	64 kbit/s Recommendation X1.
1 0 1 0 1	0.1345 kbit/s Recommendation X1.
1 0 1 1 0	0.100 kbit/s Recommendation X1.
1 0 1 1 1	0.075/1.2 kbit/s Recommendations V6 and X1 (orig-dest/dest-orig).
1 1 0 0 0	1.2/0.075 kbit/s Recommendations V6 and X1 (orig-dest/dest-orig).
1 1 0 0 1	0.050 kbit/s Recommendations V6 and X1.
1 1 0 1 0	0.075 kbit/s Recommendations V6 and X1.
1 1 0 1 1	0.110 kbit/s Recommendations V6 and X1.
1 1 1 0 0	0.150 kbit/s Recommendations V6 and X1.
1 1 1 0 1	0.200 kbit/s Recommendations V6 and X1.
1 1 1 1 0	0.300 kbit/s Recommendations V6 and X1.
1 1 1 1 1	12 kbit/s Recommendation V6.

IE Field: Intermediate rate (BC)

bits 7 6	Intermediate rate
0 0	Not used
0 1	8 kbit/s.
1 0	16 kbit/s
1 1	32 kbit/s

IE Field: Network indep. clock on Tx (BC)

bit 5
0	Not required
1	Required

IE Field: Network indep. clock on Rx (BC)

bit 4
0	Cannot accept data
1	Can accept data

IE Field: Flow control on Tx (BC)

bit 3	Flow control on Tx
0	Not required
1	Required

IE Field: Flow control on Rx (BC)

bit 2	Flow control on Rx
0	Cannot accept data
1	Can accept data

IE Field: Rate adaption header (BC)

bit 7	Rate adaption. Header
0	Not included
1	Included

IE Field: Multiple frame (BC)

bit 6	Multiple frame
0	Not supported
1	Supported

IE Field: Mode of operation (BC)

bit 5	Mode of operation
0	Bit transparent
1	Protocol sensitive

IE Field: LLI negotiation (BC)

bit 4	LLI negotiation
0	Default, LLI=256 only
1	Full protocol negotiation

IE Field: Assignor/assignee (BC)

bit 3	Assignor/assignee
0	Default assignee.
1	Assignor only

IE Field: In-band/out-band nego. (BC)

bit 2	In-band/out-band negociation
0	With USER INFO on TSC
1	In-band using LL zero

IE Field: Number of stop bits (BC)

bits 7 6	Number of stop bits
0 0	Not used
0 1	1 bit:
1 0	1.5 bits
1 1	2 bits

IE Field: Number of data bits (BC)

bits 5 4	In-band/out-band neg.
0 0	Not used
0 1	5 bits
1 0	7 bits
1 1	8 bits

IE Field: Parity (BC)

bits 3 _ 1	Parity
0 0 0	Odd
0 1 0	Even
0 1 1	None
1 0 0	Forced to 0
1 0 1	Forced to 1

IE Field: Duplex mode (BC)

bit 7	Duplex mode
0	Half duplex
1	Full duplex

IE Field: Modem type (BC)

bits 6 _ _ _ _ 1	Modem type
0 0 0 0 0 0	Reserved
0 0 0 0 0 1	V21:
0 0 0 0 1 0	V22:
0 0 0 0 1 1	V22 bis:
0 0 0 1 0 0	V23:
0 0 0 1 0 1	V26
0 0 0 1 1 0	V26 bis
0 0 0 1 1 1	V26 ter
0 0 1 0 0 0	V27
0 0 1 0 0 1	V27 bis
0 0 1 0 1 0	V27 ter
0 0 1 0 1 1	V29
0 0 1 1 0 0	V32
0 0 1 1 0 1	V35

IE Field: User inform. layer 2 prot. (BC)

bits 5 _ _ _ 1	User information layer 2 protocol
0 0 0 1 0	Recommendation Q921
0 0 1 1 0	Recommendation X25 link level

IE Field: User inform. layer 3 prot. (BC)

bits 5 _ _ _ 1	User information layer 3 protocol
0 0 0 1 0	Recommendation Q931
0 0 1 1 0	Recommendation X25 packet layer

Q931: IE Cause (CAU 0/08)

- Octet 1:	IE type
bits 8-1	08H
- Octet 3	mandatory
bits 7-6	Coding standard
bit 5	0
bits 4-1	Location
- Octet 3a:	optional
bits 7-1	Recommendation
- Octet 4:	mandatory
bits 7-5	Cause Class
bits 4-1	Cause Value
- Octet 5:	mandatory
bits 8-1	Diagnostics

Maximum length (including octet 1 and 2): 32 octets

IE Field: Coding standard (CAU)

bits 7 6	Coding standard
0 0	CCITT standardized coding
0 1	Reserved
1 0	National standard
1 1	Standard specific to location

IE Field: Location (CAU)

bits 4 _ _ 1	Location
0 0 0 0	User
0 0 0 1	Private network serving the local user
0 0 1 0	Public network serving the local user
0 0 1 1	Transit network
0 1 0 0	Public network serving the remote user
0 1 0 1	Private network serving the remote user
0 1 1 1	International network
1 0 1 0	Network beyond interworking point

IE Field: Recommendation (CAU)

bits 7 _ _ _ _ _ 1	Recommendation
0 0 0 0 0 0 0	Q931
0 0 0 0 0 1 1	X21
0 0 0 0 1 0 0	X25

IE Field: Cause Class (CAU)

bits 7 _ 5	Class
0 0 0	Normal event
0 0 1	Normal event
0 1 0	Resources unavailable
0 1 1	Service or option not available
1 0 0	Service or option not implemented
1 0 1	Invalid message (e.g parameter out of range)
1 0 1	Protocol error (e.g unknown message)
1 1 1	Internetworking

IE Field: Cause Value(CAU)

Class 7 6 5	Value 4 3 2 1	Cause number	Cause designation
0 0 0	0 0 0 0	1	Unallocated
	0 0 1 0	2	No Route to specified transit network
	0 0 1 1	3	No Route to destination
	0 1 1 0	6	Channel unacceptable
	0 1 1 1	7	Call awarded and being delivered in an establish channel
0 0 1	0 0 0 0	16	Normal call clearing
	0 0 0 1	17	User busy
	0 0 1 0	18	No user responding
	0 0 1 1	19	No answer from user
	0 1 0 1	21	Call Rejected
	0 1 1 0	22	Number changed
	1 0 1 0	26	Non-selected user clearing
	1 0 1 1	27	Destination out of order
	1 1 0 0	28	Invalid number format
	1 1 0 1	29	Facility rejected
	1 1 1 0	30	Response to STATUS ENQUIRY
	1 1 1 1	31	Normal, unspecified
0 1 0	0 0 1 0	34	No circuit/channel available
	0 1 1 0	38	Network out of order
	1 0 0 1	41	Temporary failure
	1 0 1 0	42	Switching equipement congestion
	1 0 1 1	43	Access information discarded
	1 1 0 0	44	Requested circuit/channel not available
	1 1 1 1	47	Resources unavailable, unspecified
0 1 1	0 0 0 1	49	Quality of service unavailable
	0 0 1 0	50	Requested facility not subcribed
	1 0 0 1	57	Bearer capability not authorized
	1 0 1 0	58	Bearer capability not presently available
	1 1 1 1	63	Service or option not available, unspecified
1 0 0	0 0 0 1	65	Bearer capability not implemented
	0 0 1 0	66	Channel type not implemented
	0 1 0 1	69	Requested facility not implemented
	0 1 1 0	70	Only restricted digital information bearer capability is available
	1 1 1 1	79	Service or option not implemented, unspecified
1 0 1	0 0 0 1	81	Invalid call reference value
	0 0 1 0	82	Identified channel does not exist
	0 0 1 1	83	A suspended call exists, but this call identity does not
	0 1 0 0	84	Call identity in use
	0 1 0 1	85	No call suspended
	0 1 1 0	86	Call having the requested call identity has been cleared
	1 0 0 0	88	Incompatible destination
	1 0 1 1	91	Invalid transit network selection
	1 1 1 1	95	Invalid message, unspecified
1 1 0	0 0 0 0	96	Mandatory information element is missing
	0 0 0 1	97	Message type not-existent or not implemented
	0 0 1 1	98	Message not compatible with call state or message type not-existent or not implemented
	0 0 1 1	99	Information element not-existent or not implemented
	0 1 0 0	100	Invalid information element contents
	0 1 0 1	101	Message not compatible with call state
	0 1 1 0	102	Recovery on timer expiry
	1 1 1 1	111	Protocol error unspecified
1 1 1	1 1 1 1	127	Interworking unspecified

Q931: IE Call Identity (CI 0/10)

- Octet 1:	IE type
bits 8-1	10 H
- Octets 3-n:	mandatory
bits 8-1	Call Identity (any pattern allowed, e.g. IA5 characters)

Q931: IE Call State (CS 0/14)

- Octet 1:	IE type
bits 8-1	14 H
- Octet 3:	mandatory
bits 8-7	Coding standard
bits 6-1	Call state value The contents of this field depends on the Coding standard field and the national implementation: British-Telecom ISDN protocol and Coding=CCITT British-Telecom ISDN protocol and Coding=Std defined for network France-Telecom ISDN protocol and Coding=Std defined for network All others cases (ETSI protocol and Coding=CCITT)

IE Field: Coding standard (CS)

bits 8-7	Coding standard
0 0	CCITT standardized coding
0 1	Reserved
1 0	National standard
1 1	Standard defined for the network

IE Field: Call state value (CS)
- Coding=CCITT

bits 6 _ _ _ _ 1	Call state value
	User State	Network State
0 0 0 0 0 0	U0-Null	N0-Null
0 0 0 0 0 1	U1-Call initiated	N1-Call initiated
0 0 0 0 1 0	U2-Overlap sending	N2-Overlap sending
0 0 0 0 1 1	U3-Outgoing call proceeding	N3-Outgoing call proceeding
0 0 0 1 0 0	U4-Call delivered	N4-Call delivered
0 0 0 1 1 0	U6-Call present	N6-Call present
0 0 0 1 1 0	U7-Call received	N7-Call received
0 0 1 0 0 0	U8-Connect request	N8-Connect request
0 0 1 0 0 1	U9-Incoming call proceeding	N9-Incoming call proceeding
0 0 1 0 1 0	U10-Active	N10-Active
0 0 1 0 1 1	U11-Disconnect request	N11-Disconnect request
0 0 1 1 0 0	U12-Disconnect indication	N12-Disconnect indication
0 0 1 1 1 1	U15-Suspend request	N15-Suspend request
0 1 0 0 0 1	U17-Resume request	N17-Resume request
0 1 0 0 1 1	U19-Release request	N19-Release request
0 1 1 0 0 1	U25-Overlap receiving	N25-Overlap receiving
bits 6 _ _ _ _ 1	Call state value (global interface)
0 0 0 0 0 0	REST 0 -Null
1 1 1 1 0 1	REST 1 -Restart Request
1 1 1 1 1 0	REST 2 -Restart

IE Field: Call state value (CS)
- British-Telecom protocol and Coding=CCITT

bits 6 _ _ _ _ 1	Call state value
	User State	Network State
0 1 1 0 0 1	Local Facility Request	Call active
0 1 1 0 0 1	Call abort

IE Field: Call state value (CS)
- British-Telecom protocol and Coding=Std defined for network

bits 6 _ _ _ _ 1	Call state value
	User State	Network State
0 1 1 0 0 1	Awaiting clr ind	rel req
0 1 1 0 0 1	Loc Fac Req	Call failed
0 1 1 0 0 1	Call failed

IE Field: Call state value (CS)
- France-Telecom protocol and Coding=Std defined for network

bits 6 _ _ _ _ 1	Call state value
	User State	Network State
0 1 1 0 0 1	Suppl. serv. register req

Q931: IE CHannel Identification (CHI 0/18)

- Octet 1:	IE type
bits 8-1	18 H
- Octet 3:	mandatory
bit 7	Interface identifier present
bit 6	Interface type
bit 5	0
bit 4	Preferred/exclusive
bit 3	D-Channel Indicator
bits 2-1	Information channel selection
- Octet 3.1:	optional
bits 7-1	Interface Identifier
- Octet 3.2:	mandatory if the interface type selected in octet 3 is primary interface, otherwise absent
bits 7-6	Coding standard
bit 5	Number/map
bits 4-1	Channel type
- Octet(s) 3.3:	mandatory if the interface type selected in octet 3 is primary interface, otherwise absent
bits 7-1	Channel number. This octet may be repeated to indicate multiple channels.

IE Field: Interface identifier present (CHI)

bit 7	Interface identifier present
0	Interface implicitly identified
1	Interface explicitly identified

IE Field: Interface type (CHI)

bit 6	Interface type
0	Basic rate
1	Other interfaces (Primary rate)

IE Field: Preferred/exclusive (CHI)

bit 4	Preferred/exclusive
0	Preferred
1	Exclusive

IE Field: D-channel indicator (CHI)

bit 3	D-channel indicator
0	Channel is not the D-channel
1	Channel is the D-channel

IE Field: Info channel selection (CHI)

bits 2-1	Info channel selection Basic Rate
0 0	No channel
0 1	B1 channel
1 0	B2 channel
1 1	Any channel

bits 2-1	Info channel select Primary Rate
0 0	No channel
0 1	In following octets
1 0	Reserved
1 1	Any channel

IE Field: Coding standard (CHI)

bits 7 6	Coding standard
0 0	National standard
0 1	Reserved
1 0	National Standard
1 1	Standard defined for the network

IE Field: Number / map (CHI)

bit 5	Number / map
0	Channel indicated by number
1	Channel(s) indicated by the slot map

IE Field: Channel type (CHI)

bits 4 _ _ 1	Channel type
0 0 1 1	B-channel units
0 1 1 0	H0 channel units
1 0 0 0	H11 channel units
1 0 0 1	H12 channel units

Q931: IE Facility (FAC 0/1C)

- Octet 1:	IE type
bits 8-1	1C H
- Octet 3:	mandatory
bits 7-6	0 0
bits 5-1	Service discriminator
- Octet 4:	mandatory
bits 8-7	Class
bit 6	Form
bits 5-1	Component tag
- Octet 5:	mandatory
bit 8	Length format
bits 7-1	Length of component
- Octet 6:	mandatory
bits 8-1	Component contents

IE Field: Service discriminator (FAC)

bits 5 _ _ _ 1	Service discriminator
1 0 0 0 1	Supplementary service applications

IE Field: Class (FAC)

bits 8 7	Class
1 0	Context-specific

IE Field: Form (FAC)

bit 6	Form
1	Constructor

IE Field: Component tag (FAC)

bits 5 _ _ _ 1	Component tag
0 0 0 0 1	Invoke
0 0 0 1 0	Return result
0 0 0 1 1	Return error
0 0 1 0 0	Reject

IE Field: Length format (FAC)

bit 8	Length format
0	length of the component length field in one octet

Q931: IE Progress Indicator (PI 0/1E)

- Octet 1:	IE type
bits 8-1	1E H
- Octet 3:	mandatory
bits 7-6	Coding standard
bit 5	0
bits 4-1	Location
- Octet 4:	mandatory
bits 7-1	Progress description

IE Field: Coding standard (PI)

bits 7 6	Coding standard
0 0	CCITT standardized coding
0 1	Reserved
1 0	National standard
1 1	Standard specific to location

IE Field: Location (PI)

bits 4 _ _ 1	Location
0 0 0 0	User
0 0 0 1	Private network serving the local user
0 0 1 0	Public network serving the local user
0 1 0 0	Public network serving the remote user
0 1 0 1	Private network serving the remote user
0 1 1 1	International network
1 0 1 0	Network beyond interworking point

IE Field: Progress description (PI)

bits 7 _ _ _ _ _ 1	Progress description
0 0 0 0 0 0 1	1. Not end-to-end ISDN
0 0 0 0 0 1 0	2. Destination non-ISDN
0 0 0 0 0 1 1	3. Origination non-ISDN
0 0 0 0 1 0 0	4. Returned to the ISDN
0 0 0 1 0 0 0	8. In-band information available

Q931: IE Network Specific Facilities (NSF 0/20)

- Octet 1:	IE type
bits 8-1	20 H
- Octet 3:	mandatory
bits 7-1	Length of network identification
- Octet 3.1:	mandatory
bits 7-5	Type of network identification
bits 4-1	Network identification plan
- Octet 3.2:	mandatory
bits 7-1	Network identification (IA5 characters)
- Octet 4:	mandatory
bits 7-1	Network specific facility specification

IE Field: Type of network identif. (NSF)

bits 7 _ 5	Type of network identification
0 0 0	User specified
0 1 0	National
0 1 1	International

IE Field: Network identification plan (NSF)

bits 4 _ _ 1	Network identification plan
0 0 0 0	Unknown
0 0 0 1	Carrier identification code
0 0 1 1	Data network identification code (X121)

Q931: IE Notification Indicator (NI 0/27)

- Octet 1:	IE type
bits 8-1	27 H
- Octet 3:	mandatory
bits 7-1	Notification description

IE Field: Notification description (NI)

bits 7 _ _ _ _ _ 1	Notification description
0 0 0 0 0 0 0	User suspended
0 0 0 0 0 0 1	User resumed
0 0 0 0 0 1 0	Bearer service change

Q931: IE Display (DI 0/28)

- Octet 1:	IE type
bits 8-1	28 H
- Octets 3-n:	mandatory
bits 7-1	Display information (IA5 characters)

Q931: IE Date / Time DT 0/29)

- Octet 1:	IE type
bits 8-1	29 H
- Octets 3-8:	mandatory
bits 8-1	Year
bits 8-1	Month
bits 8-1	Day
bits 8-1	Hour
bits 8-1	Minute
bits 8-1	Second

Q931: IE Keypad Facility (KF 0/2C)

- Octet 1:	IE type
bits 8-1	2C H
- Octets 3-n:	mandatory
bits 7-1	Keypad information (IA5 characters)

Q931: IE Information ReQuest (IRQ 0/32)

- Octet 1:	IE type
bits 8-1	32 H
- Octet 3:	mandatory
bit 7	Information request indicator
bits 6-1	Type of information

IE Field: Information request indicator (IRQ)

bit 1	Information request indicator
0	Information request completed
1	Prompt for additional information

IE Field: Type of information (IRQ)

bits 6 _ _ _ _ 1	Type of information
0 0 0 0 0 0	Undefined
0 0 0 0 0 1	Authorization code
0 0 0 0 1 0	Address digits
0 0 0 0 1 1	Terminal identification

Q931: IE Signal (SI 0/34)

- Octet 1:	IE type
bits 8-1	34 H
- Octet 3:	mandatory
bits 8-1	Signal value

IE Field: Signal value (SI)

bits 8 _ _ _ _ _ _ 1	Signal value
0 0 0 0 0 0 0 0	Dial tone on
0 0 0 0 0 0 0 1	Ring back tone on
0 0 0 0 0 0 1 0	Intercept tone on
0 0 0 0 0 0 1 1	Network congestion tone on
0 0 0 0 0 1 0 0	Busy tone on
0 0 0 0 0 1 0 1	Confirm tone on
0 0 0 0 0 1 1 0	Answer tone on
0 0 0 0 0 1 1 1	Call waiting tone on
0 0 0 0 1 0 0 0	off-hook warning tone on
0 0 1 1 1 1 1 1	tones off
0 1 0 0 0 0 0 0	Alerting on - pattern 0
0 1 0 0 0 0 0 1	Alerting on - pattern 1
0 1 0 0 0 0 1 0	Alerting on - pattern 2
0 1 0 0 0 0 1 1	Alerting on - pattern 3
0 1 0 0 0 1 0 0	Alerting on - pattern 4
0 1 0 0 0 1 0 1	Alerting on - pattern 5
0 1 0 0 0 1 1 0	Alerting on - pattern 6
0 0 0 0 0 1 1 1	Alerting on - pattern 7
0 1 0 0 1 1 1 1	Alerting off
	Network-specific signal values
0 0 0 1 0 0 0 1	Recall dial tone on
0 0 0 1 0 0 1 0	Barge-in tone
1 1 1 1 1 0 1 0	Incoming additional call tone
1 1 1 1 1 0 1 1	Priority additional call tone
1 1 1 1 1 1 0 1	Expensive route warning tone (F)

Q931: IE Feature Activation (FA 0/38)

- Octet 1:	IE type
bits 8-1	38 H
- Octet 3:	mandatory
bits 7-1	Feature identifier number
- Octet 3a:	optional
bits 7-1	Feature identifier number (continuation only if values 128 to 16383)

Q931: IE Feature Indication (FI 0/39)

- Octet 1:	IE type
bits 8-1	39 H
- Octet 3:	mandatory
bits 7-1	Feature identifier number
- Octet 3a:	optional
bits 7-1	Feature identifier number (continuation only if values 128 to 16383)
- Octet 4:	mandatory
bits 8-1	0 0 0 0
bits 4-1	Status indicator

IE Field: Status indicator (FI)

bits 8 _ _ _ _ _ _ 1	Signal value
0 0 0 0	Deactivated
0 0 0 1	Activated
0 0 1 0	Prompt
0 0 1 1	Pending

Q931: IE Endpoint Identifier (EI 0/3B)

- Octet 1:	IE type
bits 8-1	3B H
- Octet 3:	mandatory
bits 7-1	Use Service Identifier Coded 127 when all terminals are being selected, and octet 4 may be omitted.
- Octet 4:	optional
bit 7	Interpreter
bits 6-1	Terminal IDentifier

IE Field: Interpreter (EI)

bit 1	Interpreter
0	Terminal is selected if it is assigned the indicated TID and USID value.
1	Terminal is selected if it is not assigned the indicated TID bit, but is assigned the indicated USID value.

IE Field: Terminal IDentifier (EI)

bits 6 _ _ _ _ 1	Terminal IDentifier
x x x x x x	0 to 62 to uniquely identify a terminal.
1 1 1 1 1 1	63 when all terminals with the same USID value are being selected.

Q931: IE Service Profile Identification

- Octet 1:	IE type
bits 8-1	3A H
- Octets 3-n:	mandatory
bits 7-1	SPID (IA5 characters)

Q931: IE Information Rate (IR 0/40)

- Octet 1:	IE type
bits 8-1	40 H
- Octet 3:	mandatory
bits 7-6	0 0
bits 5-1	Incoming information rate
- Octet 4:	mandatory
bits 7-6	0 0
bits 5-1	Outgoing information rate
- Octet 5:	mandatory
bits 7-6	0 0
bits 5-1	Minimum incoming information rate
- Octet 6:	mandatory
bits 7-6	0 0
bits 5-1	Minimum outgoing information rate

IE Field: Throughput class coding (IR)

bits 5 _ _ _ 1	Signal value
0 0 0 0 0	Reserved
0 0 0 0 0	Reserved
0 0 0 0 0	Reserved
0 0 0 1 1	75
0 0 1 0 0	150
0 0 1 0 1	300
0 0 1 1 0	600
0 0 1 1 1	1200
0 1 0 0 0	2400
0 1 0 0 1	4800
0 1 0 1 0	9600
0 1 0 1 1	19200
0 1 1 0 0	48000
0 1 1 0 1	Reserved
0 1 1 1 0	Reserved
0 1 1 1 1	Reserved

Q931: IE End-to-end Transit Delay (ETD 0/42)

- Octet 1:	IE type
bits 8-1	42 H
- Octet 3:	mandatory
bits 7-3	0 0 0 0 0
bits 2-1	Cumulative transit delay value
- Octet 3a:	mandatory
bits 7-1	Cumulative transit delay value (cont)
- Octet 3b:	mandatory
bits 7-1	Cumulative transit delay value (cont)
- Octet 4:	mandatory
bits 7-3	0 0 0 0 0
bits 2-1	Requested end-to-end transit delay value
- Octet 4a:	optional
bits 7-1	Requested end-to-end transit delay value (cont)
- Octet 4b:	optional
bits 7-1	Requested end-to-end transit delay value (cont)
- Octet 5:	optional
bits 7-3	0 0 0 0 0
bits 2-1	Maximum end-to-end transit delay value
- Octet 5a:	optional
bits 7-1	Maximum end-to-end transit delay value (cont)
- Octet 5b:	optional
bits 7-1	Maximum end-to-end transit delay value (cont)

Q931: IE Packet layer binary Parameters (PP 0/44)

- Octet 1:	IE type
bits 8-1	44 H
- Octet 3:	mandatory
bits 7-6	0 0
bits 5-4	Fast select
bit 3	Expedited data
bit 2	Delivery confirmation
bit 1	Modulus

IE Field: Fast select(PP)

bits 5 4	Fast select
0 0	Fast select not requested
0 1	Fast select not requested
0 1	Fast requested with no restriction of response
1 1	Fast requested with restriction of response

IE Field: Expedited data (PP)

bit 3	Expedited data
0	No request/request denied
1	Request indicated/request accepted

IE Field: Delivery confirmation (PP)

bit 2	Delivery confirmation
0	Link-by-link confirmation
1	End-to-end confirmation

IE Field: Modulus (PP)

bit 1	Modulus
0	Modulus 8 sequencing
1	Modulus 128 sequencing

Q931: IE Packet layer Window Size (PWS 0/45)

- Octet 1:	IE type
bits 8-1	45 H
- Octet 3:	mandatory
bits 7-1	Forward value
- Octet 4:	optional
bits 7-1	Backward value

Q931: IE Packet layer Size (PS 0/46)

- Octet 1:	IE type
bits 8-1	46 H
- Octet 3:	mandatory
bits 7-1	Forward value
- Octet 4:	optional
bits 7-1	Backward value

Q931: IE CallinG Party Number (CGPN 0/6C)

- Octet 1:	IE type
bits 8-1	6C H
- Octet 3:	mandatory
bits 7-5	Type of number The contents of this field depends on the national implementation: ETSI protocol France-Telecom protocol VN3
bits 4-1	Numbering plan
- Octet 3a:	optional
bits 7-6	Presentation Indicator
bits 5-3	0 0 0
bits 2-1	Screening Indicator
- Octets 4-n:	mandatory
bits 7-1	Number digits (IA5 characters)

IE Field: Type of number (CGPN)
- ETSI protocol

bits 7 _ 5	Type of number
0 0 0	Unknown
0 0 1	International number
0 1 0	National number
0 1 1	Network specific number
1 0 0	Subscriber number
1 1 0	Abbreviated number
1 1 1	Reserved

IE Field: Type of number (CGPN)
- France-Telecom protocol VN3

bits 7 _ 5	Type of number
0 0 0	En-bloc sending
1 0 1	Overlap sending

IE Field: Numbering plan (CGPN)

bits 4 _ _ 1	Numbering plan
0 0 0 0	Unknown
0 0 0 1	ISDN/Telephony
0 0 1 1	Data
0 1 0 0	Telex
1 0 0 0	National standard
1 0 0 1	Private
1 1 1 1	Reserved

IE Field: Presentation indicator (CGPN)

bits 7 6	Screening indicator
0 0	Presentation allowed
0 1	Presentation restricted
1 0	Number not available
1 1	Reserved

IE Field: Screening indicator (CGPN)

bits 2 1	Screening indicator
0 0	User-provided, not screened
0 1	User-provided, verified and passed
1 0	User-provided, verified and failed
1 1	Network provided

Q931: IE CallinG Party Subaddress (CGPS 0/6D)

- Octet 1:	IE type
bits 8-1	6D H
- Octet 3:	mandatory
bits 7-5	Type of subaddress The contents of this field depends on the national implementation: ETSI protocol Belgium protocol
bit 4	Odd/even indicator
bits 3-1	0 0 0
- Octet 4:	mandatory if type of subaddress is NSAP
bits 7-1	Authority and Format Identifier = 50
- Octets 5-n:	mandatory
bits 7-1	Number digits (IA5 characters)

IE Field: Type of subaddress (CGPS)
- ETSI protocol

bits 7 _ 5		Type of subaddress
0 0 0		NSAP / ISO
0 1 0		User specified

IE Field: Type of subaddress (CGPS)
- Belgium protocol

bits 7 _ 5		Type of subaddress
0 0 0		User specified
0 0 1		NSAP / ISO
0 1 0		IA5 characters

IE Field: Odd/Even Indicator (CGPS )

bit 4		Odd/Even Indicator
0		Even number
1		Odd number

Q931: IE CalleD Party Number (CDPN 0/70)

- Octet 1:	IE type
bits 8-1	70 H
- Octet 3:	mandatory
bits 7-5	Type of number The contents of this field depends on the national implementation: ETSI protocol France-Telecom protocol VN3
bits 4-1	Numbering plan
- Octets 4-n:	mandatory
bit 8	0
bits 7-1	Number digits (IA5 characters)

IE Field: Type of number (CDPN)
- ETSI protocol

bits 7 _ 5	Type of number
0 0 0	Unknown
0 0 1	International number
0 1 0	National number
0 1 1	Network specific number
1 0 0	Subscriber number
1 1 0	Abbreviated number
1 1 1	Reserved

IE Field: Type of number (CDPN)
- France-Telecom protocol VN3

bits 7 _ 5	Type of number
0 0 0	En-bloc sending
1 0 1	Overlap sending

IE Field: Numbering plan (CDPN)

bits 4 _ _ 1	Numbering plan
0 0 0 0	Unknown
0 0 0 1	ISDN/Telephony
0 0 1 1	Data
0 1 0 0	Telex
1 0 0 0	National standard
1 0 0 1	Private
1 1 1 1	Reserved

Q931: IE CalleD Party Subaddress (CDPS 0/71)

- Octet 1:	IE type
bits 8-1	71 H
- Octet 3:	mandatory
bits 7-5	Type of subaddress The contents of this field depends on the national implementation: ETSI protocol Belgium protocol
bit 4	Odd/even indicator
bits 3-3	0 0 0
- Octet 4:	mandatory if type of subaddress is NSAP
bits 7-1	Authority and Format Identifier = 50
- Octets 5-n:	mandatory
bits 7-1	Number digits (IA5 characters)

IE Field: Type of subaddress (CDPS)
- ETSI protocol

bits 7 _ 5	Type of subaddress
0 0 0	NSAP / ISO
0 1 0	User specified

IE Field: Type of subaddress (CDPS)
- Belgium protocol

bits 7 _ 5	Type of subaddress
0 0 0	User specified
0 0 1	NSAP / ISO
0 1 0	IA5 characters

IE Field: Odd/Even Indicator (CDPS )

bit 4	Odd/Even Indicator
0	Even number
1	Odd number

Q931: IE Redirecting Number (RN 0/74)

- Octet 1:	IE type
bits 8-1	74 H
- Octet 3:	mandatory
bits 7-5	Type of number
bits 4-1	Numbering plan
- Octet 3a:	optional
bits 7-6	Presentation Indicator
bits 5-3	0 0 0
bits 2-1	Screening Indicator
- Octet 3b:	optional
bits 7-5	0 0 0
bits 4-1	Reason for redirection
- Octet 4:	mandatory
bits 7-1	Number digits (IA5 characters)

IE Field: Type of number (RN)

bits 7 _ 5	Type of number
0 0 0	Unknown
0 0 1	International number
0 1 0	National number
0 1 1	Network specific number
1 0 0	Subscriber number
1 1 0	Abbreviated number
1 1 1	Reserved

IE Field: Numbering plan (RN)

bits 4 _ _ 1	Numbering plan
0 0 0 0	Unknown
0 0 0 1	ISDN/Telephony
0 0 1 1	Data
0 1 0 0	Telex
1 0 0 0	National standard
1 0 0 1	Private
1 1 1 1	Reserved

IE Field: Presentation indicator (RN)

bits 7 6	Presentation indicator
0 0	Presentation allowed
0 1	Presentation restricted
1 0	Number not available
1 1	Reserved

IE Field: Screening indicator (RN)

bits 2 1	Screening indicator
0 0	User-provided, not screened
0 1	User-provided, verified and passed
1 0	User-provided, verified and failed
1 1	Network provided

IE Field: Reason for redirection (RN)

bits 4 1	Screening indicator
0 0 0 0	Call forwarding busy or called DTE busy
0 0 1 0	Call forwarding no reply
1 0 0 1	Called DTE out of order
1 1 1 1	Call forwarding unconditional or systematic call redirection
1 0 1 0	Call forwarding by the called DTE

Q931: IE RedirectioN Number (RNN 0/76)

- Octet 1:	IE type
bits 8-1	76 H
- Octet 3:	mandatory
bits 7-5	Type of number
bits 4-1	Numbering plan
- Octet 4:	mandatory
bits 7-1	Number digits (IA5 characters)

IE Field: Type of number (RNN)

bits 7 _ 5		Type of number
0 0 0		Unknown
0 0 1		International number
0 1 0		National number
0 1 1		Network specific number
1 0 0		Subscriber number
1 1 0		Abbreviated number
1 1 1		Reserved

IE Field: Numbering plan (RNN)

bits 4 _ _ 1		Numbering plan
0 0 0 0		Unknown
0 0 0 1		ISDN/Telephony
0 0 1 1		Data
0 1 0 0		Telex
1 0 0 0		National standard
1 0 0 1		Private
1 1 1 1		Reserved

Q931: IE Transit Network Selection (TNS 0/78)

- Octet 1:	IE type
bits 8-1	78 H
- Octet 3:	mandatory
bits 7-5	Type of network identification
bits 4-1	Network identification plan
- Octets 4-n:	mandatory
bits 7-1	Network identification (IA5 characters)

IE Field: Type of network identification (TNS)

bits 7 _ 5	Type of network identification
0 0 0	User specified
0 1 0	National
0 1 1	International

IE Field: Network identification plan (TNS)

bits 4 _ _ 1	Network identification plan
0 0 0 0	Unknown
0 0 0 1	Carrier identification code
0 0 1 1	Data network identification code (X121)

Q931: IE RestarT indicator (RT 0/79)

- Octet 1:	IE type
bits 8-1	79 H
- Octet 3:	mandatory
bits 7-4	0 0 0 0
bits 3-1	Class

IE Field: Class (RT)

bits 3 _ 1	Class
0 0 0	Indicated channels
1 1 0	Single interface
1 1 1	All interfaces

Q931: IE Low Layer Compatibility (LLC 0/7C)

- Octet 1:	IE type
bits 8-1	7C H
- Octet 3:	mandatory
bits 7-6	Coding standard
bits 5-1	Information transfer capability
- Octet 3a:	optional
bit 7	Negotiation indicator
bits 6-1	0 0 0 0 0 0
- Octet 4:	mandatory
bits 7-6	Transfer mode
bits 5-1	Information transfer rate
- Octet 4a:	optional
bits 7-5	Structure
bits 4-3	Configuration
bits 2-1	Establishment
- Octet 4b:	optional
bits 7-6	Symmetry
bits 5-1	Information transfer rate
- Octet 5:	optional
bits 7-6	0 1
bits 5-1	User information layer 1 protocol The contents of this field depends on the national implementation: ETSI protocol British-Telecom ISDN2 protocol
- Octet 5a:	optional
bit 7	Synchronous/asynchronous
bit 6	Negotiation
bits 5-1	User rate
- Octet 5b:	optional (V110/X30 in octet 5)
bits 7-6	Intermediate rate
bit 5	Network independent clock on Tx
bit 4	Network independent clock on Rx
bit 3	Flow control on Tx
bit 2	Flow control on Rx
- Octet 5b:	optional (V120 in octet 5)
bit 7	Rate adaption header
bit 6	Multiple frame
bit 5	Mode of operation
bit 4	LLI negotiation
bit 3	Assignor/assignee
bit 2	In-band/out-band negociation.
- Octet 5c:	optional
bits 7-6	Number of stop bits
bits 5-4	Number of data bits
bits 3-1	Parity
- Octet 5d:	optional
bit 7	Duplex mode
bits 6-1	Modem type
- Octet 6:	optional
bits 5-1	User information layer 2 protocol
- Octet 6a:	optional
bits 7-1	Optional layer 2 protocol information
- Octet 7:	optional
bits 5-1	User information layer 3 protocol
- Octet 7a:	optional
bits 7-1	Optional layer 3 protocol information

Maximum length (including octet 1 and 2): 16 octets

IE Field: Coding standard (LLC)

bits 7-6	Coding standard.
0 0	CCITT standardized coding
0 1	Reserved
1 0	National standard
1 1	Standard defined for the network

IE Field: Information transfer capab. (LLC)

bits 5 _ _ _ 1	Information transfer capability
0 0 0 0 0	Speech
0 1 0 0 0	Unrestricted digital information
0 1 0 0 1	Restricted digital information
1 0 0 0 0	3,1 kHz audio
1 0 0 0 1	7 kHz audio
1 1 0 0 0	Video

IE Field: Negotiation indicator (LLC)

bit 7	Negotiation indicator
0	Out-band negotiation not possible
1	Out-band negotiation possible

IE Field: Transfer mode (LLC)

bits 7-6	Transfer mode
0 0	Circuit mode
1 0	Packet mode

IE Field: Information transfer rate (LLC)

bits 5 _ _ _ 1	Information transfer rate
0 0 0 0 0	Packet mode code used for the calls in packet mode
1 0 0 0 0	64 kbit/s Circuit mode
1 0 0 0 1	2 x 64 kbit/s Circuit mode
1 0 0 1 1	384 kbit/s Circuit mode
1 0 1 0 1	1536 kbit/s Circuit mode
1 0 1 1 1	1920 kbit/s Circuit mode

IE Field: Structure (LLC)

bits 7 6 5	Structure
0 0 0	Default
0 0 1	8kHz integrity
1 0 0	Service data unit integrity
1 1 1	Unstructured

IE Field: Configuration (LLC)

bits 4 3	Configuration
0 0	Point-to-point

IE Field: Establishment (LLC)

bits 2 1	Establishment
0 0	Demand

IE Field: Symmetry (LLC)

bits 7 6	Establishment
0 0	Bidirectional symmetric

IE Field: User information layer 1 prot.
- ETSI protocol (LLC)

bits 5 _ _ _ 1	User information layer 1 protocol
0 0 0 0 1	Rate adaptation V110/X30
0 0 0 1 0	Recommendation G711 µ-law
0 0 0 1 1	Recommendation G711 A-law
0 0 1 0 0	Recommendation G721 32 kbit/s
0 0 1 0 1	Recommendation G722-G725 7 KHz audio :
0 0 1 1 0	Recommendation G7xx 384 kbit/s video
0 0 1 1 1	Non-CCITT rate adaptation
0 1 0 0 0	Rate adaptation V120
0 1 0 0 1	Rate adaptation X31

IE Field: User information layer 1 prot.
- British-Telecom ISDN2 protocol (LLC)

bits 5 _ _ _ 1	User information layer 1 protocol
0 0 0 0 0	Recommendation I412
0 0 0 0 1	Rate adaptation V110/X30
0 0 0 1 0	Recommendation G711 µ-law
0 0 0 1 1	Recommendation G711 A-law
0 0 1 0 0	Recommendation G721 32 kbit/s
0 0 1 0 1	Recommendation G722-G725 7 KHz audio
0 0 1 1 0	Recommendation G7xx 384 kbit/s video
0 0 1 1 1	Non-CCITT rate adaptation
0 1 0 0 0	Rate adaptation V120
0 1 0 0 1	Rate adaptation X31

IE Field: Synchronous/asyn. (LLC)

bit 7	Synchronous/asynchronous
0	Synchronous
1	Asynchronous

IE Field: Negotiation (LLC)

bit 6	Negotiation
0	Negotiation in the band not possible.
1	Negotiation in the band possible.

IE Field: User rate (LLC)

bits 5 _ _ _ 1	User rate
0 0 0 0 0	E-bits rec I460
0 0 0 0 1	0.6 kbit/s Recommendations V6 and X1.
0 0 0 1 0	1.2 kbit/s Recommendation V6.
0 0 0 1 1	2.4 kbit/s Recommendations V6 and X1.
0 0 1 0 0	3.6 kbit/s Recommendation V6.
0 0 1 0 1	4.8 kbit/s Recommendations V6 and X1.
0 0 1 1 0	7.2 kbit/s Recommendation V6.
0 0 1 1 1	8 kbit/s Recommendation I460.
0 1 0 0 0	9.6 kbit/s Recommendations V6 and X1.
0 1 0 0 1	14.4 kbit/s Recommendation V6.
0 1 0 1 0	16 kbit/s Recommendation I460.
0 1 0 1 1	19.2 kbit/s Recommendation V6.
0 1 1 0 0	32 kbit/s Recommendation I460.
0 1 1 1 0	48 kbit/s Recommendation V6 and X1.
0 1 1 1 1	56 kbit/s Recommendation V6.
1 0 0 0 0	64 kbit/s Recommendation X1.
1 0 1 0 1	0.1345 kbit/s Recommendation X1.
1 0 1 1 0	0.100 kbit/s Recommendation X1.
1 0 1 1 1	0.075/1.2 kbit/s Recommendations V6 and X1 (orig-dest/dest-orig).
1 1 0 0 0	1.2/0.075 kbit/s Recommendations V6 and X1 (orig-dest/dest-orig).
1 1 0 0 1	0.050 kbit/s Recommendations V6 and X1.
1 1 0 1 0	0.075 kbit/s Recommendations V6 and X1.
1 1 0 1 1	0.110 kbit/s Recommendations V6 and X1.
1 1 1 0 0	0.150 kbit/s Recommendations V6 and X1.
1 1 1 0 1	0.200 kbit/s Recommendations V6 and X1.
1 1 1 1 0	0.300 kbit/s Recommendations V6 and X1.
1 1 1 1 1	12 kbit/s Recommendation V6.

IE Field: Intermediate rate (LLC)

bits 7 6	Intermediate rate
0 0	Not used
0 1	8 kbit/s.
1 0	16 kbit/s
1 1	32 kbit/s

IE Field: Net. indep. clock on Tx (LLC)

bit 5
0	Not required
1	Required

IE Field: Net. indep. clock on Rx (LLC)

bit 4
0	Cannot accept data
1	Can accept data

IE Field: Flow control on Tx (LLC)

bit 3	Flow control on Tx
0	Not required
1	Required

IE Field: Flow control on Rx (LLC)

bit 2	Flow control on Rx
0	Cannot accept data
1	Can accept data

IE Field: Rate adaption header (LLC)

bit 7	Rate adaption. Header
0	Not included
1	Included

IE Field: Multiple frame (LLC)

bit 6	Multiple frame
0	Not supported
1	Supported

IE Field: Mode of operation (LLC)

bit 5	Mode of operation
0	Bit transparent
1	Protocol sensitive

IE Field: LLI negotiation (LLC)

bit 4	LLI negotiation
0	Default, LLI=256 only
1	Full protocol negotiation

IE Field: Assignor/assignee (LLC)

bit 3	Assignor/assignee
0	Default assignee.
1	Assignor only

IE Field: In-band/out-band nego. (LLC)

bit 2	In-band/out-band negociation
0	With USER INFO on TSC
1	In-band using LL zero

IE Field: Number of stop bits (LLC)

bits 7 6	Number of stop bits
0 0	Not used
0 1	1 bit:
1 0	1.5 bits
1 1	2 bits

IE Field: Number of data bits (LLC)

bits 5 4	In-band/out-band neg.
0 0	Not used
0 1	5 bits
1 0	7 bits
1 1	8 bits

IE Field: Parity (LLC)

bits 3 _ 1	Parity
0 0 0	Odd
0 1 0	Even
0 1 1	None
1 0 0	Forced to 0
1 0 1	Forced to 1

IE Field: Duplex mode (LLC)

bit 7	Duplex mode
0	Half duplex
1	Full duplex

IE Field: Modem type (LLC)

bits 6 _ _ _ _ 1	Modem type
0 0 0 0 0 0	Reserved
0 0 0 0 0 1	V21:
0 0 0 0 1 0	V22:
0 0 0 0 1 1	V22 bis:
0 0 0 1 0 0	V23:
0 0 0 1 0 1	V26
0 0 0 1 1 0	V26 bis
0 0 0 1 1 1	V26 ter
0 0 1 0 0 0	V27
0 0 1 0 0 1	V27 bis
0 0 1 0 1 0	V27 ter
0 0 1 0 1 1	V29
0 0 1 1 0 0	V32
0 0 1 1 0 1	V35

IE Field: User inform. layer 2 prot. (LLC)

bits 5 _ _ _ 1	User information layer 2 protocol
0 0 0 0 1	Basic mode ISO 1745
0 0 0 1 0	Recommendation Q921
0 0 1 1 0	Recommendation X25 link level
0 0 1 1 1	Recommendation X25 multilink
0 1 0 0 0	Extended LAPB; for half duplex operation
0 1 0 0 1	HDLC ARM
0 1 0 1 0	HDLC NRM
0 1 0 1 1	HDLC ABM
0 1 1 0 0	LAN logical control link
0 1 1 0 1	Recommendation X75 SLP

IE Field: User inform. layer 3 prot. (LLC)

bits 5 _ _ _ 1	User information layer 3 protocol
0 0 0 1 0	Recommendation Q931
0 0 1 1 0	Recommendation X25 packet layer
0 0 1 1 1	ISO 8208
0 1 0 0 0	ISO 8348
0 1 0 0 1	ISO 8473
0 1 0 1 0	Recommendation T70

Q931: IE High Layer Compatibility (HLC 0/7D)

- Octet 1:	IE type
bits 8-1	7D H
- Octet 3:	mandatory
bits 7-6	Coding standard
bits 5-3	Interpretation The contents of this field depends on the national implementation: ETSI protocol France-Telecom protocol
bits 2-1	Presentation method of protocol profile
- Octet 4:	mandatory
bits 7-1	High layer characteristics The contents of this field depends on the Coding standard field, the Interpretation field and the national implementation: France-Telecom protocol, Coding=CCITT and Interpretation= CCITT/ETSI France-Telecom protocol, Coding=National and Interpretation= CCITT/ETSI France-Telecom protocol, Coding=National and Interpretation= National Belgium protocol and Coding= CCITT Belgium protocol and Coding= National Denmark & Nordtel protocol and Coding=National All others cases (ETSI protocol and Coding=CCITT)
- Octet 4a:	optional
bits 7-1	Extended high layer characteristics

IE Field: Coding standard (HLC)

bits 7 6	Coding standard
0 0	CCITT standardized coding
0 1	Reserved
1 0	National standard
1 1	Standard defined for the network

IE Field: Interpretation (HLC)
- ETSI protocol

bits 5 _ 3	Interpretation
1 0 0	First (primary or only) high layer characteristics identification (octet 4) to be used in the call

IE Field: Interpretation (HLC)
- France-Telecom protocol

bits 5 _ 3	Interpretation
0 0 0	National
1 0 0	First (primary or only) high layer characteristics identification (octet 4) to be used in the call

IE Field: Presentation method (HLC)

bits 2 1	Presentation method
0 0	High layer protocol profile

IE Field: High layer characteristics (HLC)
- Coding=CCITT

bits 7 _ _ _ _ _ 1	High layer characteristics
0 0 0 0 0 0 1	Telephony
0 0 0 0 1 0 0	Facsimile group 2/3
0 1 0 0 0 0 1	Facsimile group 4
0 1 0 0 1 0 0	Teletex service, basic and mixed mode
0 1 0 1 0 0 0	Teletex service, basic and processable mode
0 1 1 0 0 0 1	Teletex service, basic mode
0 1 1 0 0 1 0	Interworking for Videotex
0 1 1 0 1 0 1	Telex
0 1 1 1 0 0 0	Message handling systems
1 0 0 0 0 0 1	OSI Applications
1 0 1 1 1 1 0	Reserved for maintenance
1 0 1 1 1 1 1	Reserved for management
1 1 1 1 1 1 1	Reserved

IE Field: High layer characteristics (HLC)
- France with Coding=CCITT and Interpretation=CCITT

bits 7 _ _ _ _ _ 1	High layer characteristics
0 0 0 0 0 0 1	Telephony
0 0 0 0 1 0 0	Facsimile group 2/3
0 1 0 0 0 0 1	Facsimile group 4
0 1 0 0 1 0 0	Teletex service, basic and mixed mode
0 1 0 1 0 0 0	Teletex service, basic and processable mode
0 1 1 0 0 0 1	Teletex service, basic mode
	Syntactic videotex
0 1 1 0 0 1 0	Interworking for Videotex
0 1 1 0 1 0 1	Telex
0 1 1 1 0 0 0	Message handling systems
1 0 0 0 0 0 1	OSI Applications
1 1 0 0 0 0 0	Audiovisual
1 0 1 1 1 1 0	Reserved for maintenance
1 0 1 1 1 1 1	Reserved for management
1 1 1 1 1 1 1	Reserved

IE Field: High layer characteristics (HLC)
- France with Coding=National and Interpretation=CCITT

bits 7 _ _ _ _ _ 1	High layer characteristics
0 0 0 0 0 0 0	Unknown

IE Field: High layer characteristics (HLC)
- France with Coding=National and Interpretation=National

bits 7 _ _ _ _ _ 1	High layer characteristics
0 0 0 0 0 0 0	Unknown
1 0 0 0 0 0 0	Audiography
1 0 0 1 0 0 0	Audiovideotex
1 1 1 1 1 1 1	Non-standard application

IE Field: High layer characteristics (HLC)
- Belgium and Coding=CCITT

bits 7 _ _ _ _ _ 1	High layer characteristics
0 0 0 0 0 0 1	Telephony
0 0 0 0 1 0 0	Facsimile group 2/3
	Slow scan video (CEPT) slow scan video.
0 1 0 0 0 0 1	Facsimile group 4
	Mixed mode
0 1 0 0 1 0 0	Teletex service, basic and mixed mode
0 1 0 1 0 0 0	Teletex service, basic and processable mode
0 1 1 0 0 0 1	Teletex service, basic mode
	Syntactic videotex
0 1 1 0 0 1 0	Interworking for Videotex
0 1 1 0 1 0 1	Telex
0 1 1 1 0 0 0	Message handling systems
1 0 0 0 0 0 1	OSI Applications
	Audiovisual
1 0 1 1 1 1 0	Reserved for maintenance
1 0 1 1 1 1 1	Reserved for management
1 1 1 1 1 1 1	Reserved

IE Field: High layer characteristics (HLC)
- Belgium and Coding=National

bits 7 _ _ _ _ _ 1	High layer characteristics
0 0 0 0 0 0 1	Default
0 0 0 0 1 0 0	Unknown
	X28-X31 calls
0 1 0 0 0 0 1	Siemens file transfer
	MPB file transfer

IE Field: High layer characteristics (HLC)
- Denmark & Nortel and Coding=National

bits 7 _ _ _ _ _ 1	High layer characteristics
0 0 0 0 0 0 1	SNA LU 6.2/PU 2.1
0 0 0 0 0 1 0	SNA LU 6.2/PU 2.0
0 0 0 0 0 1 1	SNA LU 6.2/PU 2.1 DIA Services
0 0 0 0 1 0 0	SNA LU 6.2/PU 2.1 SNA Distribution Services
0 0 0 0 1 0 1	SNA LU 6.2/PU 2.1 SNA Distributed Data Management
0 0 0 0 1 1 0	SNA-RJE (SNA LU 1/PU 2.0)
0 0 0 0 1 1 1	DECnet
0 0 0 1 0 0 0	IBM 3270/SNA LU 1,2,3/PU 2.0
0 0 0 1 0 0 1	Digital VT 100
0 0 0 1 0 1 0	Digital VT 200
0 0 0 1 0 1 1	IBM 5250 (SNA LU 7)
0 0 0 1 1 0 0	Kermit
0 0 0 1 1 0 1	New textcommunication service based on T.62 protocol

IE Field: Extended high layer char. (HLC)

bits 7 _ _ _ _ _ 1	Extended high layer characteristics
0 0 0 0 0 0 1	Telephony
0 0 0 0 1 0 0	Facsimile group 2/3
0 1 0 0 0 0 1	Facsimile group 4
0 1 0 0 1 0 0	Teletex service, basic and mixed mode
0 1 0 1 0 0 0	Teletex service, basic and processable mode
0 1 1 0 0 0 1	Teletex service, basic mode
0 1 1 0 0 1 0	Interworking for Videotex
0 1 1 0 1 0 1	Telex
0 1 1 1 0 0 0	Message handling systems
1 0 0 0 0 0 1	OSI Applications
1 0 1 1 1 1 0	Reserved for maintenance
1 0 1 1 1 1 1	Reserved for management
1 1 1 1 1 1 1	Reserved

Q931: IE User-User (UU 0/7E)

- Octet 1:	IE type
bits 8-1	7E H
- Octet 3:	mandatory
bits 8-1	Protocol discriminator The contents of this field depends on the national implementation: ETSI protocol France-Telecom protocol
- Octet 4:	mandatory
bits 8-1	User information

IE Field: Protocol discriminator (UU)
- ETSI protocol

bits 8 _ _ _ _ _ _ 1	Protocol discriminator
0 0 0 0 0 0 0 1	User specific protocol
0 0 0 0 0 0 0 1	OSI high layer protocol
0 0 0 0 0 0 1 0	Recommendation X244
0 0 0 0 0 0 1 0	Reserved for system management convergence function
0 0 0 0 0 1 0 0	IA5 characters
0 0 0 0 0 1 0 0	CCITT Recommendation V120 rate adaption
0 0 0 0 1 0 0 0	Q931 user-network call control messages

IE Field: Protocol discriminator (UU)
- France-Telecom protocol

bits 8 _ _ _ _ _ _ 1	Protocol discriminator
0 0 0 0 0 1 0 0	IA5 characters
	NT2-to-NT2 facilities
	TRANSGROUP facilities

Codeset 0 ETSI

Q931: IE Connected Number (CN 0/8C)

- Octet 1:	IE type
bits 8-1	8C H
- Octet 3:	mandatory
bits 7-5	Type of number The contents of this field depends on the national implementation: ETSI protocol France-Telecom protocol VN3
bits 4-1	Numbering plan
- Octet 3a:	optional
bits 7-6	Presentation Indicator
bits 5-3	0 0 0
bits 2-1	Screening Indicator
- Octets 4-n:	mandatory
bits 7-1	Number digits (IA5 characters)

IE Field: Type of number (CN)
- ETSI protocol

bits 7 _ 5	Type of number
0 0 0	Unknown
0 0 1	International number
0 1 0	National number
0 1 1	Network specific number
1 0 0	Subscriber number
1 1 0	Abbreviated number
1 1 1	Reserved

IE Field: Type of number (CN)
- France-Telecom protocol VN3

bits 7 _ 5	Type of number
0 0 0	En-bloc sending
1 0 1	Overlap sending

IE Field: Numbering plan (CN)

bits 4 _ _ 1	Numbering plan
0 0 0 0	Unknown
0 0 0 1	ISDN/Telephony
0 0 1 1	Data
0 1 0 0	Telex
1 0 0 0	National standard
1 0 0 1	Private
1 1 1 1	Reserved

IE Field: Presentation indicator (CN)

bits 7 6	Screening indicator
0 0	Presentation allowed
0 1	Presentation restricted
1 0	Number not available
1 1	Reserved

IE Field: Screening indicator (CN)

bits 2 1	Screening indicator
0 0	User-provided, not screened
0 1	User-provided, verified and passed
1 0	User-provided, verified and failed
1 1	Network provided

Q931: IE Connected Subaddress (COS 0/8D)

- Octet 1:	IE type
bits 8-1	8D H
- Octet 3:	mandatory
bits 7-5	Type of subaddress The contents of this field depends on the national implementation: ETSI protocol Belgium protocol
bits 4-1	Odd/even indicator
- Octet 4:	mandatory if type of subaddress is NSAP
bits 7-1	Authority and Format Identifier = 50
- Octets 5-n:	mandatory
bits 7-1	Number digits (IA5 characters)

IE Field: Type of subaddress (COS)
- ETSI protocol

bits 7 _ 5	Type of subaddress
0 0 0	NSAP / ISO
0 1 0	User specified

IE Field: Type of subaddress (COS)
- Belgium protocol

bits 7 _ 5	Type of subaddress
0 0 0	NSAP / ISO
0 1 0	User specified
	IA5 characters

IE Field: Odd/Even Indicator (COS )

bit 4	Odd/Even Indicator
0	Even number
1	Odd number

Codeset 5 (National-specific) Belgium

Q931: IE Charge Advice (Belgium) (CA/B 5/1A)

- Octet 1:	IE type
bits 8-1	1A H
- Octet 3:	mandatory
bits 7-6	Coding standard
bit 5	CEPT standard
bits 3-1	Type of charging
- Octet 3a:	optional
bits 7-1	Charging period
- Octet 3a/b:	optional
bits 7-1	Charging period multiplier binary coded value.
- Octets 4, ...:	optional
bits 8-1	Number of charging units binary coded value up to 16777215 (24 bits)

IE Field: Coding standard (CA/B)

bits 7-6	Coding standard
0 0	CCITT standardized
0 1	Other international standards
1 0	National standard
1 1	Standard defined for the network side

IE Field: CEPT standard (CA/B)

bit 5	CEPT standard
0	CEPT standard
1	National standard

IE Field: Type of charging (CA/B)

bits 3 - 1	Type of charging
0 0 0	Free of charge
0 0 1	Charge on duration
0 1 0	Charge on answer
0 1 1	Charge increment
1 0 0	(Sub)-total charge

IE Field: Charging period (CA/B)

bits 7 _ _ _ _ _ 1	Charging period
0 0 0 1 0 0 0	0,1 second interval
0 0 0 1 0 0 1	1 second interval
0 0 0 1 0 1 0	10 seconds interval
0 0 0 1 0 1 1	1 minute interval

Codeset 5 (National-specific) Bellcore National ISDN

Q931: IE Operator System Access (OSA 5/1D)

- Octet 1:	IE type
bits 8-1	1D H
- Octet 3:	mandatory
bits 7-3	0 0 0 0 0: Unspecified
bits 2-1	Type of access

IE Field: Type of access (OSA)

bits 2 1	Notification description
0 0	Public/principal: default operator system.
0 1	Public/ alternate: operator system determined by user subscription.

Codeset 6 (Network-specific) FT-Numeris

Q931: IE User Capability (France) (UC/F 6/24)

- Octet 1:	IE type
bits 8-1	24 H
- Octet 3:	mandatory
bits 8-7	Coding standard
bits 6-1	Description

IE Field: Coding standard (UC/F)

bits 8-7	Coding standard
1 0	National standard

IE Field: Description (UC/F)

bits 6 _ _ _ _ 1	Description
0 0 0 0 0 0	TE or NT2 in national mode

Q931: IE User-User Facility (France) (UUF/F 6/7A)

- Octet 1:	IE type
bits 8-1	7A H
- Octet 3:	mandatory
bits 8-1	Protocol discriminator
- Octet 4:	mandatory
bits 8-1	User information

IE Field: Protocol discriminator (UUF)

bits 8 _ _ _ _ _ _ 1	Protocol discriminator
0 1 0 0 0 0 0 0	NT2 to NT2 facilities
0 1 0 0 0 0 0 1	IA5 characters

Codeset 6 (Network-specific) Bellcore National ISDN

Q931: IE RedirectinG Subaddress (RGS 6/75)

- Octet 1:	IE type
bits 8-1	75 H
- Octet 3:	mandatory
bits 7-5	Type of subaddress
bit 4	Odd/even indicator
bits 3-1	0 0 0
- Octets 4-n:	mandatory
bits 7-1	Subaddress information

IE Field: Type of subaddress (RGS)

bits 7 _ 5	Type of subaddress
0 0 0	NSAP / ISO
0 1 0	User specified

IE Field: Odd/Even Indicator (RGS )

bit 4	Odd/Even Indicator
0	Even number
1	Odd number

Q931: IE Call Appearance (CA 6/7B)

- Octet 1:	IE type
bits 8-1	7B H
- Octet 3:	mandatory
bits 7-1	Call appearance identifier
- Octet 3a:	optional
bits 7-1	Call appearance identifier continuation, if needed for values 128 to 16383.

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updated: 27-Feb-04

ITU-Q931 Information Elements

Codeset 0

Q931: IE Segmented Message (SM 0/00)

IE Field: First segment indicator (SM)

Q931: IE Bearer Capability (BC 0/04)

IE Field: Coding standard (BC)

IE Field: Information transfer capab. (BC)

IE Field: Transfer mode (BC)

IE Field: Information transfer rate (BC)

IE Field: Structure (BC)

IE Field: Configuration (BC)

IE Field: Establishment (BC)

IE Field: Symmetry (BC)

IE Field: User information layer 1 prot. - ETSI protocol (BC)

IE Field: User information layer 1 prot. - British-Telecom ISDN2 protocol (BC)

IE Field: Synchronous/asynch. (BC)

IE Field: Negotiation (BC)

IE Field: User rate (BC)

IE Field: Intermediate rate (BC)

IE Field: Network indep. clock on Tx (BC)

IE Field: Network indep. clock on Rx (BC)

IE Field: Flow control on Tx (BC)

IE Field: Flow control on Rx (BC)

IE Field: Rate adaption header (BC)

IE Field: Multiple frame (BC)

IE Field: Mode of operation (BC)

IE Field: LLI negotiation (BC)

IE Field: Assignor/assignee (BC)

IE Field: In-band/out-band nego. (BC)

IE Field: Number of stop bits (BC)

IE Field: Number of data bits (BC)

IE Field: Parity (BC)

IE Field: Duplex mode (BC)

IE Field: Modem type (BC)

IE Field: User inform. layer 2 prot. (BC)

IE Field: User inform. layer 3 prot. (BC)

Q931: IE Cause (CAU 0/08)

IE Field: Coding standard (CAU)

IE Field: Location (CAU)

IE Field: Recommendation (CAU)

IE Field: Cause Class (CAU)

IE Field: Cause Value(CAU)

Q931: IE Call Identity (CI 0/10)

Q931: IE Call State (CS 0/14)

IE Field: Coding standard (CS)

IE Field: Call state value (CS) - Coding=CCITT

IE Field: Call state value (CS) - British-Telecom protocol and Coding=CCITT

IE Field: Call state value (CS) - British-Telecom protocol and Coding=Std defined for network

IE Field: Call state value (CS) - France-Telecom protocol and Coding=Std defined for network

Q931: IE CHannel Identification (CHI 0/18)

IE Field: Interface identifier present (CHI)

IE Field: Interface type (CHI)

IE Field: Preferred/exclusive (CHI)

IE Field: D-channel indicator (CHI)

IE Field: Info channel selection (CHI)

IE Field: Coding standard (CHI)

IE Field: Number / map (CHI)

IE Field: Channel type (CHI)

Q931: IE Facility (FAC 0/1C)

IE Field: Service discriminator (FAC)

IE Field: Class (FAC)

IE Field: Form (FAC)

IE Field: Component tag (FAC)

IE Field: Length format (FAC)

Q931: IE Progress Indicator (PI 0/1E)

IE Field: Coding standard (PI)

IE Field: Location (PI)

IE Field: Progress description (PI)

Q931: IE Network Specific Facilities (NSF 0/20)

IE Field: Type of network identif. (NSF)

IE Field: Network identification plan (NSF)

Q931: IE Notification Indicator (NI 0/27)

IE Field: Notification description (NI)

Q931: IE Display (DI 0/28)

Q931: IE Date / Time DT 0/29)

Q931: IE Keypad Facility (KF 0/2C)

Q931: IE Information ReQuest (IRQ 0/32)

IE Field: Information request indicator (IRQ)

IE Field: Type of information (IRQ)

Q931: IE Signal (SI 0/34)

IE Field: User information layer 1 prot.
- ETSI protocol (BC)

IE Field: User information layer 1 prot.
- British-Telecom ISDN2 protocol (BC)

IE Field: Call state value (CS)
- Coding=CCITT

IE Field: Call state value (CS)
- British-Telecom protocol and Coding=CCITT

IE Field: Call state value (CS)
- British-Telecom protocol and Coding=Std defined for network

IE Field: Call state value (CS)
- France-Telecom protocol and Coding=Std defined for network

IE Field: Type of number (CGPN)
- ETSI protocol

IE Field: Type of number (CGPN)
- France-Telecom protocol VN3

IE Field: Type of subaddress (CGPS)
- ETSI protocol

IE Field: Type of subaddress (CGPS)
- Belgium protocol

IE Field: Type of number (CDPN)
- ETSI protocol

IE Field: Type of number (CDPN)
- France-Telecom protocol VN3

IE Field: Type of subaddress (CDPS)
- ETSI protocol

IE Field: Type of subaddress (CDPS)
- Belgium protocol

IE Field: User information layer 1 prot.
- ETSI protocol (LLC)

IE Field: User information layer 1 prot.
- British-Telecom ISDN2 protocol (LLC)