SIST ETS 300 099 E2:2003

• Abstract:

  This specification defines a network-internal interface for the provision of ISDN packet-mode services. This specification shall be used if a specific implementation alternative for these services is used in an ISDN. The implementation alternatives & exact location of the interface are defined in the specification. The second edition will contain further enhancements of the PHI.

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.080 - Integrated Services Digital Network (ISDN)
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: ETSI ETS 300 099 ed.2 (1998-04) - Integrated Services Digital Network (ISDN); Specification of the Packet Handler access point Interface (PHI)

SIST ETS 300 099 E2:2003 is the Slovenian adoption of ETS 300 099 Edition 2 from ETSI. It specifies the Packet Handler access point Interface (PHI), a network-internal interface for ISDN packet-mode services, and defines how a local Connection Related Function (CRF) and a Packet Handler (PH) exchange signalling, data, provisioning and maintenance information. It is written for ISDN implementations, and also for the packet-service interface used in GSM Public Land Mobile Networks (PLMNs), where this specific architecture is chosen.

What does SIST ETS 300 099 E2:2003 specify?

SIST ETS 300 099 E2:2003 specifies the PHI and the conditions under which it is used in an ISDN or a GSM PLMN. The standard is for the implementation alternative where the Packet Handling Function is not fully contained in the local CRF, so a manufacturer-independent interface is needed between the local CRF and the PH.

The document is organized into clauses on scope, normative references, definitions and abbreviations, reference configuration and functional model, supported services, basic interface structure, interface configuration, Operations, Administration and Maintenance (OA&M), frame multiplexing, PHI signalling, static and dynamic provisioning, exception handling, and additional Information Elements (IEs). It then adds annexes that give signalling diagrams, coding details, reset and maintenance procedures, and support for private telecommunication networks.

Annex	What it covers
A	Requirements on the common channel signalling system
B	PHI signalling diagrams
C	Additional information for Permanent Virtual Circuits (PVCs) on switched long-duration B-channel access, case B
D	Multi-PRA configurations
E	Switch-over and concentration procedures
F	Reset procedures
G	Layer 2 SDL diagrams and state tables
H	Coding of the BC and LLC Information Element (IE)
J	SDL for management frame continuity check
K	Maintenance Flow for PMBS provided on the D-channel
L	Support of Private Telecommunication Networks (PTNs)

What are the key requirements of SIST ETS 300 099 E2:2003?

SIST ETS 300 099 E2:2003 defines the interface structure, service types, signalling, and maintenance behaviour needed for packet-mode access through the PHI. In practice, it tells implementers how to split responsibilities between the CRF and the PH, how channels are used, and how the network should react when links are established, cleared, or fail.

Access architecture and channel use

• Clause 4 places the PHI between the local CRF and the PH/InterWorking Function. For case A services, the PH acts like the Access Unit. In practice, this fixes where packet-service functions sit in the network.
• Clause 6 defines the PHI as a Primary Rate Access (PRA) with a 30B+D channel structure. The D64-channel is reserved for call control signalling for the B-channels, unless only semi-permanent B-channels are supported. This matters because the slot plan and signalling path have to match the defined PRA structure.
• Clause 6 also separates B-channels into Bb-channels for user B-channel packet-mode services and Bd-channels for user D-channel packet-mode services. The PH selects the time slot for new switched Bb or Bd channels, and the Bb/Bd distribution is agreed between the CRF-P and the PH. This affects capacity planning and how channel pools are assigned.

Supported services and service behaviour

• Clause 5 covers both case A and case B services, including B-channel and D-channel access, point-to-point and point-to-multipoint access, and basic and primary rate user access. The same service behaviour is required whether access is local or remote, so operators and vendors must keep the user view consistent.
• Clause 5.1 lists the supported service forms: semi-permanent, switched, and long-duration B-channel access, plus semi-permanent, PLL, long-duration PLL, and switched D-channel access. In practice, this means the PHI has to support both fixed and on-demand packet-service arrangements.
• Clause 5.3 covers numbering, addressing and terminal selection. The standard ties service access to identifiers such as E.164 and X.121 numbering, CRF-S identity, FH reference and LIC, which is important for routing, subscription data and terminal selection.

Signalling, multiplexing and timers

• Clauses 9 and 10 define how Bd-channels carry multiple data links and signalling. Clause 9 uses a unique Data Link Connection Identifier (DLCI) structure, with SAPI 16 for subscriber data links and a separate signalling data link for management. This is what lets several logical links share one physical Bd-channel.
• Clause 9.7 defines Bd-channel continuity checking, with a default both-way procedure and optional HDLC flag or one-way alternatives. Clause 9.9 also defines peer busy behaviour, and Annex G shows the Layer 2 state-table impact of the two timer values for T200. In practice, the PH and CRF-S must agree how channel health is monitored and how congestion is handled.
• Clause 10 defines the signalling messages for switched B-channel services, dynamically provisioned semi-permanent and switched Bd-channels, switched D-channel services, and restart on the D64-channel. It also defines timers T320, TPHI, TPH and TCRF, which control when data links and channels are released after calls or failures. These timers matter because they determine how long resources stay reserved and when recovery starts.

Provisioning, maintenance and fault handling

• Clause 11 covers static and dynamic provisioning for PLL and semi-permanent services, including registration and deregistration procedures. It also uses the facility IE for dynamic provisioning. This is the part to implement when services are pre-provisioned or activated by signalling.
• Clause 8 defines PHI-related OA&M only where CRF-P/S and PH coordination is needed. It covers administration, operations and maintenance at Layers 1, 2 and 3, including provisioning of semi-permanent Bb/Bd-channels, status and performance monitoring, and signalling-related maintenance.
• Clause 12 lists the exception cases for outgoing and incoming calls, call collision, missing channels, disconnection and data transfer failures. It also covers corrupted user-user IEs and repeated DLCI conditions. This is where the standard tells implementers how to fail cleanly and keep both sides aligned.
• Clauses 13 and Annex H define the additional IEs and their coding, including DLCI value, Bd-channel reference number, FH reference number, additional subscriber information, type of service, called party number and cause. Implementers need these codes so that the PHI signalling messages can be interpreted correctly.

What terms does SIST ETS 300 099 E2:2003 define?

• Packet Handler access point Interface (PHI) - The standardized network-internal interface between the local CRF and the PH for packet-mode service provision.
• Connection Related Function (CRF-P / CRF-S) - CRF-P is the CRF physically connected to the PH, while CRF-S is the CRF to which subscribers are connected.
• Bb-channel - A B-channel of the PRA used for user B-channel packet-mode services.
• Bd-channel - A B-channel of the PRA used for user D-channel packet-mode services.
• Preallocated Logical Link (PLL) - A pre-provisioned D-channel logical link; the note says this was called “Permanent Logical Link” in edition 1.
• Bundle - All Bd-channels of a PHI leading to a particular CRF-S.
• Sub-bundle - All Bd-channels of a PHI leading to a particular Frame Handler (FH) within the CRF-S.
• Data Link Connection Identifier (DLCI) - The identifier used on Bd-channels to distinguish one logical data link from another.

Who uses SIST ETS 300 099 E2:2003?

SIST ETS 300 099 E2:2003 is used by network designers, access-network engineers, switch and Packet Handler vendors, and operators of ISDN or GSM PLMN packet services. It is also relevant to test laboratories and quality teams that need to verify PHI signalling, provisioning, reset, maintenance flow and channel handling.

In practice, these users apply the standard when they are:

• designing the CRF-P/PH boundary
• allocating Bb and Bd channels on a PRA
• implementing B-channel or D-channel packet services
• defining subscriptions, numbering and terminal selection
• building OA&M and fault-handling functions
• testing conformance of signalling messages, timers and state behaviour

What changed in SIST ETS 300 099 E2:2003 from the previous edition?

SIST ETS 300 099 E2:2003 is the second edition of the standard and replaces edition 1. The foreword lists these main technical changes:

• PHI use for Public Land Mobile Network (PLMN) packet services
• removal of the detailed selection mechanism for incoming calls
• alignment with ETS 300 048 edition 2 and ETS 300 049 edition 2

Which standards are used with SIST ETS 300 099 E2:2003?

Standard	What it contributes
CCITT Recommendation I.130	General stage structure for describing telecom services
CCITT Recommendation I.324	ISDN network architecture and the local CRF / PHF roles
ETS 300 007	Case A PSPDN services and packet-mode terminal support
ETS 300 048	Case B PMBS on the B-channel
ETS 300 049	PMBS on the D-channel
ETS 300 011	Primary rate user-network interface layer 1 specification and test principles
ETS 300 402-2	Bd-channel data-link procedures and Layer 2 behaviour used as the basis for Bd-channel multiplexing
ETS 300 403-1	DSS1 signalling procedures and coding used for PHI signalling and information elements
ITU-T Recommendation Q.921	ISDN user-network interface data link layer specification
ITU-T Recommendation Q.931	ISDN user-network interface layer 3 basic call control
ITU-T Recommendation Q.932	Generic supplementary-service procedures and facility IE handling
ITU-T Recommendation X.25 / X.25PLP	Packet-layer procedures and packet-mode service behaviour
ITU-T Recommendation X.31 / I.462	Support of packet-mode terminal equipment by ISDN
ITU-T Recommendation X.121	International numbering plan for public data networks
ITU-T Recommendation Q.850	Cause and location coding for call clearing and exception handling
ETS 300 603	Interworking between PLMN and PSPDN/ISDN packet-switched data services

What does the SIST ETS 300 099 E2:2003 document contain?

The document contains the reference configurations and functional models for local and remote PHI access, plus the service overview that links access methods to procedures. It also contains signalling message sets, procedure descriptions, and coding rules for the PHI-specific Information Elements.

Annexes B, G and J provide signalling diagrams, state tables and SDL examples, which are useful for implementation and test development. Annexes E, F and K specify switch-over, reset and maintenance-flow procedures, while Annex H gives the Bearer Capability and Lower Layer Compatibility coding needed for correct call setup and packet-mode access.

SLOVENSKI STANDARD
01-december-2003
'LJLWDOQRRPUHåMH]LQWHJULUDQLPLVWRULWYDPL,6'1±6SHFLILNDFLMDYPHVQLND
GRVWRSRYQHWRþNHSDNHWQHJDVWUHåQLND3+,
Integrated Services Digital Network (ISDN); Specification of the Packet Handler access
point Interface (PHI)
Ta slovenski standard je istoveten z: ETS 300 099 Edition 2
ICS:
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN ETS 300 099
TELECOMMUNICATION April 1998
STANDARD Second Edition
Source: NA Reference: RE/NA-023206
ICS: 33.020
Key words: Access, interface, ISDN, PHI
Integrated Services Digital Network (ISDN);
Specification of the Packet Handler access point Interface (PHI)
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE
Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
Internet: [e-mail] - http://www.etsi.fr - http://www.etsi.org
Tel.: [phone] - Fax: [phone]
Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1998. All rights reserved.

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ETS 300 099: April 1998
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.

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ETS 300 099: April 1998
Contents
Foreword .11
1 Scope .13
2 Normative references.14
3 Definitions and abbreviations .15
3.1 Definitions .15
3.2 Abbreviations .17
4 Reference configuration and functional model.17
4.1 Reference configuration.17
4.2 Basic functional model.18
4.3 Functional model for remote access to the PHI.20
5 Services supported by the PHI specification.21
5.1 Basic service aspects .21
5.1.1 Services provided on the B-channel.22
5.1.1.1 Semi-permanent B-channel access .22
5.1.1.2 Switched B-channel access.22
5.1.1.3 Switched long-duration B-channel access (case B) .22
5.1.2 Services provided on the D-channel (case B).23
5.1.2.1 Semi-permanent D-channel access .23
5.1.2.2 PLL access .23
5.1.2.3 Long duration PLL access .23
5.1.2.4 Switched D-channel access .24
5.1.3 Subscription and related data.24
5.2 Detailed service aspects.25
5.2.1 Notification of incoming calls.25
5.2.1.1 No Notification class .25
5.2.1.2 Conditional Notification class.25
5.2.2 Mapping of Information Elements (IEs).26
5.2.3 Access connection release.26
5.2.4 Access collision.26
5.2.5 Cause mappings .26
5.3 Numbering, addressing and terminal selection.26
5.3.1 Numbering and addressing .27
5.3.2 Terminal selection and compatibility checking .28
5.3.3 Directory number and services association.28
5.4 Services cross-reference and conformance statement for the PHI.28
6 Basic interface structure.30
6.1 General .30
6.2 Interface architecture for PHI.30
6.2.1 Local PHI access.30
6.2.2 Remote PHI access .30
6.3 PHI channel types.32
6.3.1 D64-channel .32
6.3.2 Bb-channels (case A and case B).33
6.3.3 Bd-channels .34
6.3.3.1 Data transfer.34
6.3.3.2 Link layer management .35
7 Interface configuration.36
7.1 FH function at the CRF-S .36
7.2 Multi-PRA PHI configuration .36

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ETS 300 099: April 1998
8 Operations, Administration and Maintenance (OA&M). 36
8.1 General. 36
8.1.1 Scope. 36
8.1.2 Definitions . 37
8.1.3 Principles . 37
8.2 Layer 1 OA&M requirements. 37
8.2.1 Administration. 37
8.2.1.1 Provisioning of semi-permanent Bb-channels . 37
8.2.1.2 Provisioning of semi-permanent Bd-channels . 37
8.2.2 Operations and maintenance. 38
8.2.2.1 Primary Rate Access (PRA). 38
8.2.2.2 Establishment and release of switched Bd-channels due
to operational requirements . 38
8.2.2.3 Re-establishment of dynamically provisioned
semi-permanent Bd-channels in case of failure. 38
8.3 Layer 2 OA&M requirements. 38
8.3.1 Bb-channels. 38
8.3.2 Bd-channels. 38
8.3.2.1 Administration . 38
8.3.2.2 Operations. 38
8.3.2.2.1 General status and performance
monitoring . 38
8.3.2.2.2 Load sharing. 39
8.3.2.3 Maintenance. 39
8.3.3 D64-channel . 39
8.4 Layer 3 OA&M requirements. 39
8.4.1 Service support. 39
8.4.1.1 ITU-T Recommendation X.25 Packet Layer Procedures
(X.25PLP). 39
8.4.1.2 PVCs on the D-channel. 40
8.4.2 Signalling (D64 and Bd-inband). 40
8.4.2.1 Administration . 40
8.4.2.2 Operations. 40
8.4.2.2.1 D64-signalling. 40
8.4.2.2.2 Bd-inband signalling. 40
8.4.2.3 Maintenance. 40
8.4.2.3.1 D64-signalling. 40
8.4.2.3.2 Bd-inband signalling. 40
9 Frame multiplexing on the Bd-channels . 41
9.1 Principle. 41
9.2 Address field layout . 42
9.3 Subscriber data links. 43
9.4 Signalling data link . 43
9.4.1 The DLCI value of the signalling data link . 43
9.4.2 Establishment of the signalling data link. 43
9.4.3 Signalling data link failure . 43
9.4.4 Recovery of the signalling data link . 43
9.5 Switchover and concentration . 44
9.6 Reset procedures. 44
9.7 Bd-channel continuity check. 44
9.7.1 HDLC flag continuity check procedure . 45
9.7.2 Management frame continuity check procedure. 45
9.7.2.1 Both-way procedure description. 45
9.7.2.2 One-way procedure description . 46
9.7.2.3 Management frame layouts . 46
9.7.2.4 Parameter set . 46
9.8 Connection verification procedure. 47
9.9 Peer busy procedures . 47
9.10 Default timer values . 47
9.11 Maintenance flow . 48
10 PHI signalling. 48

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ETS 300 099: April 1998
10.1 General introduction.48
10.1.1 Signalling procedures.48
10.1.2 Signalling messages .48
10.1.3 IEs .48
10.2 B-channel services, switched, case A .49
10.2.1 Signalling messages .49
10.2.1.1 Call proceeding.50
10.2.1.2 Connect .50
10.2.1.3 Connect acknowledge .50
10.2.1.4 Disconnect.50
10.2.1.5 Release.51
10.2.1.6 Release complete.51
10.2.1.7 Setup .51
10.2.1.8 Status.52
10.2.1.9 Status enquiry.52
10.2.2 Case A, procedures for an outgoing call (CRF-P to PH).52
10.2.3 Case A, procedures for an incoming call (PH to CRF-P).53
10.2.4 Case A, procedures for call clearing .54
10.3 B-channel services, switched, case B .54
10.3.1 Signalling messages .54
10.3.1.1 Call proceeding.55
10.3.1.2 Connect .55
10.3.1.3 Connect acknowledge .55
10.3.1.4 Disconnect.55
10.3.1.5 Release.56
10.3.1.6 Release complete.56
10.3.1.7 Setup .56
10.3.1.8 Status.57
10.3.1.9 Status enquiry.57
10.3.2 Case B, procedures for an outgoing call (CRF-P to PH).57
10.3.3 Case B, procedures for an incoming call (PH to CRF-P).58
10.3.4 Case B, procedures for call clearing .59
10.4 Dynamically provisioned semi-permanent and switched Bd-channels .59
10.4.1 Signalling messages for circuit mode procedures.60
10.4.1.1 Connect .60
10.4.1.2 Setup .60
10.4.2 Signalling messages for packet mode procedures .60
10.4.2.1 Connect .61
10.4.2.2 Setup .61
10.4.3 Procedures for Bd-channels established by the CRF-S (CRF-P to PH) .61
10.4.4 Procedures for Bd-channels established by the PH (PH to CRF-P) .62
10.4.5 Procedures for Bd-channel access connection clearing .63
10.5 D-channel services, switched, case B .63
10.5.1 Signalling messages .64
10.5.1.1 Connect .64
10.5.1.2 Release.64
10.5.1.3 Release complete.65
10.5.1.4 Setup .65
10.5.1.5 Status.66
10.5.2 Procedures for data link establishment by the CRF-S (CRF-S to PH).66
10.5.3 Procedures for data link establishment by the PH (PH to CRF-S).67
10.5.4 Procedures for data link disconnection .69
10.5.5 Procedures after receipt of a STATUS message.70
10.6 Restart on the D64-channel.70
10.6.1 Signalling messages .70
10.6.1.1 Restart .71
10.6.1.2 Restart acknowledge .71
10.6.1.3 Status.71
10.6.2 Restart procedure.71
10.7 The timers T320, TPHI, TPH, and TCRF .72
11 Static and dynamic provisioning for PLL and semi-permanent services.72
11.1 General Introduction .72

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11.1.1 Signalling procedures . 72
11.1.2 Signalling messages. 73
11.1.3 IEs. 73
11.2 B-channel services, case A and case B, semi-permanent. 73
11.2.1 Static provisioning. 73
11.2.2 Dynamic provisioning. 73
11.3 Semi-permanent Bd-channels. 73
11.3.1 Static provisioning. 73
11.3.2 Dynamic provisioning. 73
11.3.3 Deregistration of dynamically provisioned Bd-channels . 73
11.4 D-channel services, PLL . 74
11.4.1 PLL data link provisioning, static . 74
11.4.2 Messages for dynamic provisioning of PLL data links. 74
11.4.2.1 Register. 74
11.4.2.2 Release complete . 75
11.4.2.3 The linked identifier of the invoke component . 75
11.4.2.4 The argument of the invoke component . 75
11.4.2.5 The result of the return result component. 76
11.4.2.6 The error value of the return error component. 76
11.4.2.7 The parameter of the return error component . 76
11.4.3 Procedures for PLL data link registration by the CRF-S (CRF-S to PH) . 76
11.4.4 Procedures for PLL data link registration by the PH (PH to CRF-S) . 77
11.4.5 Procedures for PLL data link deregistration . 78
11.5 D-channel services, semi-permanent . 79
11.5.1 Semi-permanent data link provisioning, static . 79
11.5.2 Messages for dynamic provisioning of semi-permanent data links . 79
11.5.3 Procedures for semi-permanent data link registration. 79
11.5.4 Procedures for semi-permanent data link deregistration. 79
12 Exception handling . 79
12.1 B-channel service (case A and B). 79
12.1.1 Outgoing call. 79
12.1.2 Incoming call. 79
12.1.2.1 Unsuccessful call . 79
12.1.2.2 Premature clearing by remote terminal. 80
12.1.2.3 No Bb-channel available . 80
12.1.2.4 Data link disconnect. 80
12.1.2.5 Acceptance of call on existing B-channel . 80
12.1.3 Call collision. 80
12.1.4 Data transfer phase . 80
12.1.4.1 Subscriber disconnects data link . 80
12.1.4.2 Bb-channel is cleared. 80
12.1.4.3 Restart on PHI. 81
12.2 Bd-channel establishment. 81
12.2.1 Bd-channel establishment by the CRF-S. 81
12.2.1.1 Corrupted "user-user" information element. 81
12.2.2 Bd-channel establishment by the PH. 81
12.2.2.1 Corrupted "user-user" information element. 81
12.3 Switched D-channel service. 81
12.3.1 Exception resolution using layer 2 procedures . 82
12.3.1.1 Exception reporting on the UNI. 82
12.3.1.2 No exception reporting. 82
12.3.1.3 Exception reporting on the Bd-channel. 82
12.3.2 Outgoing call. 82
12.3.2.1 No Bd-channel available . 82
12.3.2.2 Signalling data link disconnection . 82
12.3.2.3 Data link establishment rejection . 83
12.3.2.4 Repeated DLCI . 83
12.3.3 Incoming call. 83
12.3.3.1 Unsuccessful call . 83
12.3.3.2 Premature clearing by remote terminal. 83
12.3.3.3 No Bd-channel available . 84
12.3.3.4 Signalling data link disconnection . 84

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12.3.3.5 Acceptance of call on existing data link.84
12.3.3.6 Repeated DLCI.84
12.3.3.7 Data link disconnect .84
12.3.4 Call collision.84
12.3.5 Data transfer phase.85
12.3.5.1 Subscriber disconnects data link.85
12.3.5.2 Bd-channel is cleared .85
12.3.5.3 Restart on PHI .85
12.4 PLL or semi-permanent D-channel service .85
12.4.1 Outgoing call .85
12.4.1.1 No Bd-channel available.85
12.4.1.2 SETUP with PLL (semi-permanent) DLCI value.85
12.4.1.3 SABME with unknown DLCI .85
12.4.2 Incoming call .86
12.4.2.1 No Bd-channel available.86
12.4.2.2 SABME with unknown DLCI .86
12.4.3 Call collision.86
12.4.3.1 Call collision on network-user interface .86
12.4.3.2 Call collision on the Bd-channel.86
12.4.4 Data transfer phase.86
12.5 PLL or semi-permanent registration or deregistration .86
12.5.1 Registration and deregistration by the CRF-S.86
12.5.1.1 Data link disconnection.86
12.5.1.2 Repeated DLCI.87
12.5.1.3 Unknown deregistration parameter .87
12.5.2 Registration or deregistration by the PH.87
12.5.2.1 Data link disconnection.87
12.5.2.2 Repeated "called party number" .87
12.5.2.3 Repeated DLCI.87
12.5.2.4 Unknown deregistration parameter .87
13 Additional IEs for PHI signalling .88
13.1 Coding rules.88
13.2 Coding of the additional IEs.90
13.2.1 DLCI value.90
13.2.2 Bd-channel reference number.90
13.2.3 FH reference number .91
13.2.4 Additional subscriber information .91
13.2.5 Type of service .91
13.2.6 Called party number .92
13.2.7 Cause .92
13.3 Coding of the facility Information Element .92
13.3.1 Embedded IEs.93
13.3.2 Operation value .93
13.3.3 Error value.93
Annex A (informative): Requirements on the common channel signalling system .94
Annex B (informative): PHI signalling diagrams.95
B.1 Introduction.95
B.1.1 Conventions for the diagrams.95
B.2 B-channel services case A.98
B.2.1 B-channel establishment .98
B.2.2 B-channel disconnection.100
B.3 B-channel services case B.102
B.3.1 B-channel establishment .102
B.4 Dynamic Bd-channels .107
B.4.1 Bd-channel establishment .107

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B.5 Data link establishment and release. 111
B.5.1 D-channel data link establishment . 111
B.5.2 D-channel link disconnection . 117
B.6 Bd-channel establishment, semipermanent . 119
B.7 Dynamic provisioning for D-channel PLL service . 121
B.7.1 PLL data link registration. 121
B.7.2 PLL data link deregistration. 123
B.8 Dynamic provisioning for D-channel semi-permanent service . 125
B.8.1 Semi-permanent data link registration . 125
B.8.2 Semi-permanent data link deregistration . 126
Annex C (informative): Additional information for PVCs on switched long-duration B-channel access
(case B). 127
C.1 Introduction. 127
C.2 Procedure . 127
C.2.1 Identification . 127
C.2.2 B-channel establishment. 127
C.2.3 Layer 2 and layer 3 establishment . 127
C.2.4 Error procedures . 127
C.2.5 Procedures for VCs on B-channels supporting PVCs. 127
Annex D (informative): Multi-PRA configurations . 128
D.1 Selection by using numbers. 128
D.2 Selection by a hunting algorithm or a call deflection mechanism . 128
D.3 Non-associated signalling. 128
Annex E (normative): Switch-over and concentration procedures . 129
E.1 Introduction. 129
E.2 Applicability. 129
E.3 Constraints. 129
E.4 Procedures . 129
E.4.1 Switchover procedures. 129
E.4.1.1 Switchover during link establishment. 129
E.4.1.2 Switchover of an established link. 130
E.4.2 Detailed procedure. 130
E.5 Traffic management considerations . 130
E.5.1 Bd-channel failure or malfunction. 130
E.5.2 Unexpected overload . 131
E.5.3 Concentration of under-loaded Bd-channels. 131
E.6 Modifications to the main part of the specification. 131
E.6.1 General interface architecture. 131
E.6.2 Data transfer . 131
E.6.3 Load sharing. 131
E.6.4 Bd-inband signalling . 132
E.6.5 Switchover and concentration procedure. 132
E.6.6 Procedures for data link establishment by the CRF-S . 132
E.6.7 Bd-channel is cleared. 132
E.6.8 Call collision on the Bd-channel . 132

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ETS 300 099: April 1998
Annex F (normative): Reset procedures .133
F.1 Procedure.133
F.2 Coding .133
Annex G (informative): Layer 2 SDL diagrams and state tables .135
G.1 SDL diagrams.135
G.2 Key to the state transition tables .138
G.2.1 Definition of a cell of the state transition table .138
G.2.2 Key to the contents of a cell.138
G.3 State transition tables.138
Annex H (normative): Coding of the BC and LLC Information Element (IE) .140
H.1 BC IE for circuit switched bearer capability .140
H.2 LCC information element for case A services.141
H.3 BC information element for packet mode bearer capability .142
H.3.1 BC for Bb-channel establishment .142
H.3.2 BC for Bd-channel establishment .142
H.4 BC information element in the Bd-channel signalling link .142
Annex J (informative): SDL for management frame continuity check .143
Annex K (normative): Maintenance Flow for PMBS provided on the D-channel.147
K.1 General.147
K.2 Applicability.147
K.3 Coding principles.147
K.3.1 Maintenance frame layouts.147
K.3.2 Message format.148
K.3.2.1 Loop request .148
K.3.2.2 Loop response.148
K.3.3 IEs coding .149
K.3.3.1 Message type .149
K.3.3.2 Loop originator .149
K.3.3.3 Loop destination .150
K.3.3.4 Diagnostic.150
K.3.3.5 Test data .151
K.4 Procedures.151
K.4.1 General .151
K.4.2 Loop procedure.151
K.4.2.1 Loop request message generation by the PH.152
K.4.2.2 Loop request message relaying .152
K.4.2.3 Loop request message reception by the requested loop destination.152
K.4.2.4 Loop response message generation by the actual loop destination .153
K.4.2.5 Loop response message relaying .153
K.4.2.6 Loop message reception by the Packet Handler (PH) .153
K.4.2.7 Time-out of the loop timer .153
K.4.2.8 Loop timer value.153
K.4.3 Forward compatibility procedures.153
Annex L (normative): Supp
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