B.2 Low Layer/High Layer Compatibility Information Element

07.013GPPGeneral on Terminal Adaptation Functions (TAF) for Mobile Stations (MS)TS

B.2.1 Introduction

B.2.1.1 General Consideration

The purpose of the Low Layer/High Layer Compatibility Information Element (LLC/HLC-IE) is to provide a means for additional end-to-end compatibility checking by an addressed entity (e.g. a remote user, an interworking unit or a high layer function network node). The LLC/HLC-IE may be manipulated by the GSM PLMN to maintain consistency with the setup parameter negotiation between the mobile station and the network (ref. to GSM TS 09.07). The LLC/HLC-IE is transferred transparently by the ISDN between the call originating GSM PLMN and the addressed entity.

With respect to the individual parameter settings at the MS the following cases may be distinguished (ref. GSM 07.02 and GSM 07.03):

– Mobile-originated call set up by a MS consisting of a MT with R interface:

The setting results from respective MMI actions and/or MT internal settings.

– Mobile-originated call set up by a MS consisting of a MT with S interface:

The LLC/HLC-IEs which are contained in the ISDN SETUP message received from the terminal are passed unchanged to the MSC.

– Mobile-terminated call set up to a MS consisting of a MT with R interface:

The LLC/HLC related part of the compatibility check is carried out according to the knowledge of the MT concerning its implemented functions (i.e. answering the call). The offered field values determine the selection of the terminal function for the intended connection.

– Mobile-terminated call set up to a MS consisting of a MT with S interface:

The LLC/HLC received from the MSC is passed to the terminal by the MT. The LLC/HLC related part of the compatibility check is up to the terminal connected to the S interface of the MT, as is the selection of the terminal function (i.e. answering the call).

Where applicable, the same settings and rules concerning LLC and/or HLC apply as for ISDN use (ref. ETS 300 102‑1 and ETR 018). However, considering that GSM PLMN data transmission is based on CCITT V.110 rate adaptation, the MS shall provide the LLC-IE for mobile-originated calls when using unrestricted or restricted digital information transfer capability. This is to assure the conveyance of the e.g. "V.110" indication towards the called entity, as the comparable indication in the ISDN BC-IE may be lost. It shall also be possible to choose whether or not the LLC-IE is provided for the case of an information transfer capability "3.1 kHz audio ex PLMN".

There shall be no contradiction of the information between the BC-IE and LLC-IE at the originating side. However, as some parts of the bearer capability may be modified during the transport of the call, there should be minimum duplication of this information between the BC-IE and the LLC-IE.

If as a result of duplication, a contradiction occurs between the BC-IE and the LLC-IE at the terminating side, the receiving entity shall ignore the conflicting information in the LLC-IE.

B.2.1.2 Interpretation of the Tables

The individual contents of the LLC/HLC-IE are represented in the following tables. The indication of the applicable service group defines the link between the GSM BC-IE and its associated LLC/HLC-IEs.

If the appropriate message includes multiple BC-IEs and if LLC and/or HLC information is available, multiple LLCs and HLCs shall be included in the message. The LLC/HLC associated with the BC-IE indicating speech shall be marked as "not applicable" (see GSM 04.08).

Legend: { xxxx | yyyy } choice of values

—- not relevant for this service (set to appropriate value)

[ zzzz ] optional

B.2.2 LLC Bearer Service 21 … 26

B.2.2.1 Unrestricted / restricted digital information transfer capability

Low layer compatibility information element:

╔═════╤═════════════════════════════════════════╤═══════════════════════════════════════════════════════════╗
║Octet│ Information element field │ field value ║
╠═════╪═════════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 3 │ Coding standard │ CCITT ║
║ │ Information transfer capability │ { unrestricted digital | restricted digital } ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 4 │ Transfer mode │ circuit mode ║
║ │ Information transfer rate │ 64 kbit/s ║
╠═════╪═╤═══════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 5 │ │ User information layer 1 protocol │ { V.110/X.30 | V.120 } ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5a │ │ Synchronous / asynchronous │ asynchronous ║
║ │ │ Negotiation │ in-band not possible ║

║ │ │ User rate │ { 0.3 | 1.2 | 2.4 | 4.8 | 9.6 | 1.2/0.075 | ║

║ │ │ │ 14.4 | 19.2 | 28.8 | 38.4 | 48 | 56 } kbit/s ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5b │ │ Intermediate rate │ { 8 | 16 } kbit/s ║
║ 2)│ │ NIC on Tx │ —– ║
║ │ │ NIC on Rx │ —– ║
║ │ │ Flow control on Tx │ { not required 1)| required } ║
║ │ │ Flow control on Rx │ { not accepted 1)| accepted } ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5b │ │ Rate adaption header / no header │ Rate adaption header included ║
║ 3)│ │ Multiple frame establishment support │ Multiple frame establishment supported ║
║ │ │ Mode of operation │ Protocol sensitive mode of operation ║
║ │ │ Assignor / assignee │ —– ║
║ │ │ In-band / out-band negotiation │ —– ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5c │ │ Number of stop bits │ { 1 | 2 } bits ║
║ │ │ Number of data bits │ { 7 | 8 } bits ║
║ │ │ Parity │ { odd | even | none | forced to 0 | forced to 1 } ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5d │ │ Duplex mode │á[ duplex ] ║
║ │ │ Modem type │ —– ║
╚═════╧═╧═══════════════════════════════════════╧═══════════════════════════════════════════════════════════╝

1) only these values are applicable to Mobile Originated Calls;

2) octet 5b for V.110/X.30;

3) octet 5b for V.120.

B.2.2.2 3.1 kHz audio ex-PLMN information transfer capability

Low layer compatibility information element:

╔═════╤═════════════════════════════════════════╤═══════════════════════════════════════════════════════════╗
║Octet│ Information element field │ field value ║
╠═════╪═════════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 3 │ Coding standard │ CCITT ║
║ │ Information transfer capability │ 3.1kHz audio ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 4 │ Transfer mode │ circuit mode ║
║ │ Information transfer rate │ 64 kbit/s ║
╠═════╪═╤═══════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 5 │ │ User information layer 1 protocol │ G.711 A-law ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5a │ │ Synchronous / asynchronous │ (may be set depending on ║
║ │ │ Negotiation │ user’s requirement) ║
║ │ │ User rate │ ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5b │ │ Intermediate rate │ ║
║ │ │ NIC on Tx │ not relevant ║
║ │ │ NIC on Rx │ but cannot be omitted ║
║ │ │ Flow control on Tx │ in order to have octet 5d ║
║ │ │ Flow control on Rx │ ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5c │ │ Number of stop bits │ (may be set depending on ║
║ │ │ Number of data bits │ the user’s requirement) ║
║ │ │ Parity │ ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5d │ │ Duplex mode │á[ duplex ] ║
║ │ │ Modem type │á[{V.21|V.22|V.22bis|V.23|V.26ter|V.32|V.34}] ║
╚═════╧═════════════════════════════════════════╧═══════════════════════════════════════════════════════════╝

NOTE: If octet 5d is not specified, the whole LLC is not required.

B.2.3 LLC Bearer Service 31 … 34

B.2.3.1 Unrestricted / restricted digital information transfer capability

Low layer compatibility information element:

╔═════╤═════════════════════════════════════════╤═══════════════════════════════════════════════════════════╗
║Octet│ Information element field │ field value ║
╠═════╪═════════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 3 │ Coding standard │ CCITT ║
║ │ Information transfer capability │ { digital unrestricted | restricted digital } ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 4 │ Transfer mode │ circuit mode ║
║ │ Information transfer rate │ 64 kbit/s ║
╠═════╪═╤═══════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 5 │ │ User information layer 1 protocol │ { V.110/X.30 | X.31 flag stuffing | V.120 } ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5a │ │ Synchronous / asynchronous │ synchronous ║
║ │ │ Negotiation │ in-band not possible ║
║ │ │ User rate │ { 1.2 | 2.4 | 4.8 | 9.6 | ║

║ │ │ │ 14.4 | 19.2 | 28.8 | 38.4 | 48 | 56 } kbit/s ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5b │ │ Intermediate rate │ { 8 | 16 } kbit/s ║
║ 2)│ │ NIC on Tx │ { not required | required } ║
║ │ │ NIC on Rx │ { not accepted | accepted } ║
║ │ │ Flow control on Tx │ —– ║
║ │ │ Flow control on Rx │ —– ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5b │ │ Rate adaption header / no header │ Rate adaption header included ║
║ 3)│ │ Multiple frame establishment support │ Multiple frame establishment supported ║
║ │ │ Mode of operation │ Protocol sensitive mode of operation ║
║ │ │ Assignor / assignee │ —– ║
║ │ │ In-band / out-band negotiation │ —– ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5c │ │ Number of stop bits │ not relevant ║
║ 1)│ │ Number of data bits │ but cannot be omitted ║
║ │ │ Parity │ in order to have octet 5d ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5d │ │ Duplex mode │á[ duplex ] ║
║ 1)│ │ Modem type │ —– ║
╠═════╪═╧═══════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 6 │ User information layer 2 protocol │á[ X.25 ] ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 7 │ User information layer 3 protocol │á[ X.25 ] ║
╚═════╧═════════════════════════════════════════╧═══════════════════════════════════════════════════════════╝

1) If octet 5d is not specified, octet 5c may be omitted.

2) octet 5b for V.110/X.30

3) octet 5b for V.120

B.2.3.2 3.1kHz audio ex-PLMN information transfer capability

Low layer compatibility information element:

╔═════╤═════════════════════════════════════════╤═══════════════════════════════════════════════════════════╗
║Octet│ Information element field │ field value ║
╠═════╪═════════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 3 │ Coding standard │ CCITT ║
║ │ Information transfer capability │ 3.1kHz audio ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 4 │ Transfer mode │ circuit mode ║
║ │ Information transfer rate │ 64 kbit/s ║
╠═════╪═╤═══════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 5 │ │ User information layer 1 protocol │ G.711 A-law ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5a │ │ Synchronous / asynchronous │ (may be set depending on ║
║ │ │ Negotiation │ the user’s requirement) ║
║ │ │ User rate │ ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5b │ │ Intermediate rate │ ║
║ │ │ NIC on Tx │ not relevant ║
║ │ │ NIC on Rx │ but cannot be omitted ║
║ │ │ Flow control on Tx │ in order to have octet 5d ║
║ │ │ Flow control on Rx │ ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5c │ │ Number of stop bits │ (may be set depending on ║
║ │ │ Number of data bits │ the user’s requirement) ║
║ │ │ Parity │ ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5d │ │ Duplex mode │á[ duplex ] ║
║ │ │ Modem type │á[ { V.22 | V.22bis | V.26ter | V.32 | | V.34 } ] ║
╠═════╪═╧═══════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 6 │ User information layer 2 protocol │á[ X.25 ] ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 7 │ User information layer 3 protocol │á[ X.25 ] ║
╚═════╧═════════════════════════════════════════╧═══════════════════════════════════════════════════════════╝

NOTE: If octet 5d is not specified, octets 5a..5d may be omitted.

B.2.4 LLC Bearer Services 41 … 46

May be optionally available with the settings according to B.2.2.1.

B.2.5 LLC Bearer Services 51 … 53

B.2.5.1 Unrestricted digital information transfer capability

Low layer compatibility information element:

╔═════╤═════════════════════════════════════════╤═══════════════════════════════════════════════════════════╗
║Octet│ Information element field │ field value ║
╠═════╪═════════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 3 │ Coding standard │ CCITT ║
║ │ Information transfer capability │ unrestricted digital ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 4 │ Transfer mode │ circuit mode ║
║ │ Information transfer rate │ 64 kbit/s ║
╠═════╪═╤═══════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 5 │ │ User information layer 1 protocol │ X.31 flag stuffing ║
╟─────┼─┼───────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 5a │ │ Synchronous / asynchronous │ synchronous ║
║ │ │ Negotiation │ in-band not possible ║
║ │ │ User rate │ { 2.4 | 4.8 | 9.6 | ║

14.4 | 19.2 | 28.8 | 38.4 | 48 | 56 } kbit/s
╠═════╪═╧═══════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 6 │ User information layer 2 protocol │ X.25 ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 7 │ User information layer 3 protocol │ X.25 ║
╚═════╧═════════════════════════════════════════╧═══════════════════════════════════════════════════════════╝

B.2.6 LLC Bearer Service 61

B.2.6.1 3,1 kHz audio ex-PLMN information transfer capability, Asynchronous

Ref. section B.2.2.2.

B.2.6.2 3,1 kHz audio ex-PLMN information transfer capability, Synchronous

Ref. section B.2.3.2.

B.2.7 LLC Bearer Service 81

B.2.7.1 3,1 kHz audio ex-PLMN information transfer capability, Asynchronous

Ref. section B.2.2.2.

B.2.7.2 3,1 kHz audio ex-PLMN information transfer capability, Synchronous

Ref. section B.2.3.2.

B.2.8 HLC Teleservices 11 … 12

High layer compatibility information element:

╔═════╤═════════════════════════════════════════╤═══════════════════════════════════════════════════════════╗
║Octet│ Information element field │ Field value ║
╠═════╪═════════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 3 │ Coding standard │ CCITT ║
║ │ Interpretation │ first high layer characteristic identification to be ║
║ │ │ used in the call ║
║ │ Presentation method of protocol profile │ high layer protocol profile ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 4 │ High layer characteristics identific. │ Telephony ║
╚═════╧═════════════════════════════════════════╧═══════════════════════════════════════════════════════════╝

B.2.9 HLC Teleservices 21 … 23

Not applicable.

B.2.10 HLC Teleservice 61

High layer compatibility information element:

╔═════╤═════════════════════════════════════════╤═══════════════════════════════════════════════════════════╗
║Octet│ Information element field │ Field value ║
╠═════╪═════════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 3 │ Coding standard │ CCITT ║
║ │ Interpretation │ first high layer characteristic identification to be ║
║ │ │ used in the call ║
║ │ Presentation method of protocol profile │ high layer protocol profile ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 4 │ High layer characteristics identific. │ Facsimile G2/G3 ║
╚═════╧═════════════════════════════════════════╧═══════════════════════════════════════════════════════════╝

B.2.11 HLC Teleservice 62

High layer compatibility information element:

╔═════╤═════════════════════════════════════════╤═══════════════════════════════════════════════════════════╗
║Octet│ Information element field │ Field value ║
╠═════╪═════════════════════════════════════════╪═══════════════════════════════════════════════════════════╣
║ 3 │ Coding standard │ CCITT ║
║ │ Interpretation │ first high layer characteristic identification to be ║
║ │ │ used in the call ║
║ │ Presentation method of protocol profile │ high layer protocol profile ║
╟─────┼─────────────────────────────────────────┼───────────────────────────────────────────────────────────╢
║ 4 │ High layer characteristics identific. │ Facsimile G2/G3 ║
╚═════╧═════════════════════════════════════════╧═══════════════════════════════════════════════════════════╝

Annex C (Informative):
Change Request History

SMG#

SPEC

CR

PHASE

VERS

NEW_VERS

SUBJECT

S16

07.01

A004

5.0.0

Data Compression

S17

07.01

A010

2+

5.0.1

Editorial

S18

07.01

A013

2+

5.0.1

5.1.0

MT Adapters

S19

07.01

A015

2+

5.1.0

5.2.0

New GSM Profile for Packet Services

S20

07.01

A016

2+

5.2.0

5.3.0

Correction for Data Compression

s21

07.01

A017

2+

5.3.0

5.4.0

V.120 Interworking and RDI

s21

07.01

A018

2+

5.3.0

5.4.0

Correction of Data Compression

s21

07.01

A019

2+

5.3.0

5.4.0

HSCSD

s21

07.01

A020

2+

5.3.0

5.4.0

Support of 14.4 kbit/s (Radio interface related)

s22

07.01

A021

2+

5.4.0

5.5.0

Provide interworking at higher rates than 28.8 kbit/s (as 33.6 kbit/s).

s22

07.01

A022

2+

5.4.0

5.5.0

Correction 14.4 and synchronization

s22

07.01

A023

2+

5.4.0

5.5.0

Initial synchronization for HSCSD

s23

07.01

A023

R96

5.5.0

5.6.0

Initial synchronization for HSCSD

s23

07.01

A024

R96

5.5.0

5.6.0

Corrections for 14.4 kbit/s

s23

07.01

A025

R96

5.5.0

5.6.0

Clarifications on ACC parameter values

s23

07.01

A026

R96

5.5.0

5.6.0

Deletion of codepoint for V.32bis

s24

07.01

A027

R96

5.6.0

5.7.0

Editorial Modification for HSCSD

s24

07.01

A028

R96

5.6.0

5.7.0

Valid combinations of HSCSD parameters

s24

07.01

A029

R96

5.6.0

5.7.0

LLC Handling in GBS

s25

07.01

A030

R96

5.7.0

5.8.0

Setting of ACC, Correction of network behaviour

s25

07.01

A031

R96

5.7.0

5.8.0

UIMI is a negotiable parameter

07.01

5.8.0

5.8.1

Version update for publication

s28

07.01

A033

R96

5.8.1

5.9.0

Use of Octet 6f of GSM BC