ETSI ETS 300 175-4 ed.1 (1992-10)

SLOVENSKI STANDARD
01-december-2003
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Radio Equipment and Systems (RES); Digital European Cordless Telecommunications
(DECT) Common interface Part 4: Data link control layer
Ta slovenski standard je istoveten z: ETS 300 175-4 Edition 1
ICS:
33.070.30 'LJLWDOQHL]EROMãDQH Digital Enhanced Cordless
EUH]YUYLþQHWHOHNRPXQLNDFLMH Telecommunications (DECT)
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35.100.20 Podatkovni povezovalni sloj Data link layer
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN ETS 300 175-4
TELECOMMUNICATION October 1992
STANDARD
Source: ETSI TC-RES Reference: DE/RES 3001-4
ICS: 33.060
DECT
Key words:
Radio Equipment and Systems (RES);
Digital European Cordless Telecommunications (DECT)
Common interface
Part 4: Data link control layer
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
F-06921 Sophia Antipolis CEDEX - FRANCE
Postal address:
650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
Office address:
c=fr, a=atlas, p=etsi, s=secretariat - secretariat@etsi.fr
X.400: Internet:
Tel.: +33 92 94 42 00 - Fax: +33 93 65 47 16
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 1992. All rights reserved.
New presentation - see History box

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ETS 300 175-4: October 1992
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 300 175-4: October 1992
Contents
Foreword.9
1 Scope .11
2 Normative references .12
3 Definitions, symbols and abbreviations .13
3.1 DLC Layer definitions .13
3.2 DLC Layer abbreviations .15
4 Data link control layer overview .18
4.1 General.18
4.2 C-Plane data link service .18
4.3 C-plane broadcast service .20
4.4 U-plane services .20
4.5 Lower layer management entity.20
5 C-plane service characteristics. 21
5.1 Data link service (LAPC+Lc) .21
5.1.1 General . 21
5.1.2 LAPC types of operation. 22
5.1.3 Establishment of information transfer modes .22
5.1.3.1 Data Link Identifier (DLI). 22
5.1.3.2 LAPC states. 22
5.2 Broadcast service (Lb) .23
6 Frame structures for C-plane services .24
6.1 Data link service frame structure .24
6.1.1 General frame structure. 24
6.1.2 Lc frame delimiting and transparency.25
6.1.3 Transmission order.25
6.1.4 Routing to logical channels.26
6.1.4.1 C logical channel.26
F
6.1.4.2 C logical channel .26
S
6.1.5 Invalid frames .27
6.2 Broadcast service frame structure.27
6.2.1 Standard frame structure. 27
6.2.2 Extended frame structure.28
7 Elements of procedures and formats of fields for C-plane peer to peer communication.28
7.1 General.28
7.2 Address field formats .28
7.3 Address field parameters.28
7.3.1 REServed bit (RES) .28
7.3.2 Command Response bit (C/R). 29
7.3.3 SAPI field .29
7.3.4 New Link Flag bit (NLF) .29
7.3.5 LLN-field.29
7.3.6 Data link identifiers.29
7.4 Control field formats. 30
7.5 Control field parameters .30
7.5.1 Poll/Final bit P/F.30
7.5.2 Multiple frame operation variables and sequence numbers.30
7.5.2.1 Modulus.30

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ETS 300 175-4: October 1992
7.5.2.2 Send state Variable V(S).31
7.5.2.3 Acknowledge state Variable V(A).31
7.5.2.4 Send sequence Number N(S).31
7.5.2.5 Receive state Variable V(R) .31
7.5.2.6 Receive sequence Number N(R) .31
7.5.3 Unacknowledged operation variables and sequence numbers.31
7.5.4 Supervisory and Unnumbered function bits S and U .31
7.6 Length indicator field format .32
7.7 Length indicator field parameters.32
7.7.1 Length indicator field extension bit; N .32
7.7.2 More data bit; M .32
7.7.3 Length parameter; LI.32
7.7.4 Extended length parameter; L .33
JJ
7.7.5 Reserved bit; RES.33
7.8 Fill field format .33
7.9 Checksum field format.33
7.10 Checksum field parameters.34
7.11 Commands and responses.35
7.11.1 Information (I) command.35
7.11.2 Receive Ready (RR) command/response.36
7.11.3 Receive Not Ready (RNR) command/response.36
7.11.4 REJect (REJ) command/response.36
7.11.5 Set Asynchronous Balanced Mode (SABM) command.36
7.11.6 Disconnect Mode (DM) response.37
7.11.7 Unnumbered Information (UI) command.37
7.11.8 DISConnect (DISC) command.37
7.11.9 Unnumbered ACK (UA) response.37
8 Primitives.38
8.1 Primitive types .38
8.2 Primitives to the MAC layer (lower layer) .38
8.3 Primitives to network layer (higher layer).38
8.3.1 Parameter definitions.38
8.3.2 S-SAP primitives .40
8.3.2.1 DL-ESTABLISH primitive .40
8.3.2.2 DL-RELEASE primitive.40
8.3.2.3 DL-DATA primitive .40
8.3.2.4 DL-UNIT-DATA primitive.41
8.3.2.5 DL-SUSPEND primitive.41
8.3.2.6 DL-RESUME primitive.41
8.3.2.7 DL-ENC_KEY primitive.41
8.3.2.8 DL-ENCRYPT primitive .42
8.3.3 B-SAP primitives .42
8.3.3.1 DL-BROADCAST primitive.42
8.3.3.2 DL-EXPEDITED primitive .42
8.4 Primitives to the interworking unit.42
8.4.1 Parameter definitions.42
8.4.2 LU -SAP primitives .43
X
8.4.2.1 DL-U-DATA primitive.43
8.4.2.2 DL-U-UNIT-DATA primitive .43
8.4.2.3 DL-U-ERROR primitive.44
9 C-plane peer to peer procedures.45
9.1 General .45
9.2 Point to point acknowledged operation.45
9.2.1 Procedure for the use of the P/F bit.45
9.2.1.1 Class A acknowledged information transfer.45
9.2.1.2 Class B acknowledged information transfer.45
9.2.2 Use of LLN.46
9.2.2.1 Class A operation .46

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ETS 300 175-4: October 1992
9.2.2.2 Class B operation .46
9.2.3 Link establishment and information transfer in class A operation.46
9.2.3.1 Establishing class A operation .46
9.2.3.2 Class A acknowledged information transfer .47
9.2.3.4 Reception of class A I-frames.47
9.2.3.5 Receiving acknowledgements.48
9.2.3.6 Waiting for acknowledgement.48
9.2.3.7 Release of class A operation. 49
9.2.3.8 Re-establishment of class A operation.49
9.2.4 Establishing class B multiple frame operation.49
9.2.4.1 Overview .49
9.2.4.2 Class B multiple frame establishment procedures.50
9.2.4.3 Class B LLN assignment procedures.51
9.2.4.3.1 PT establishment.51
9.2.4.3.2 FT establishment.52
9.2.5 Link maintenance and information transfer in class B multiple frame
operation .52
9.2.5.1 Transmitting I-frames.52
9.2.5.2 Receiving I-frames.53
9.2.5.2.1 P bit set to 1.53
9.2.5.2.2 P bit set to 0.53
9.2.5.3 Sending and receiving acknowledgements .54
9.2.5.3.1 Sending acknowledgements.54
9.2.5.3.2 Receiving acknowledgements.54
9.2.5.4 Receiving REJ-frames.54
9.2.5.5 Receiving RNR-frames.55
9.2.5.6 LAPC own receiver busy condition .57
9.2.5.7 Waiting acknowledgement.57
9.2.6 Release of class B multiple frame operation.58
9.2.7 Link suspension and resumption .59
9.2.7.1 Link suspension.59
9.2.7.1.1 Class B acknowledged suspend .59
9.2.7.1.2 Unacknowledged suspend.60
9.2.7.2 Class B link resumption.60
9.2.7.3 Connection handover.62
9.2.7.3.1 Class A connection handover.63
9.2.7.3.2 Class B connection handover.63
9.2.7.3.3 Expiry of connection handover timer.64
9.2.8 Re-establishment of class B multiframe operation.64
9.2.8.1 Criteria for re-establishment . 64
9.2.9 Exception handling.66
9.2.9.1 General .66
9.2.9.2 Class B exception condition reporting and recovery.66
9.2.9.2.1 N(S) sequence error.66
9.2.9.2.2 N(R) sequence error.66
9.2.9.2.3 Timer recovery condition.67
9.3 Unacknowledged operation .67
9.3.1 Use of LLN for unacknowledged information transfer. 67
9.3.2 Class U link establishment.67
9.3.3 Unacknowledged information transfer.67
9.3.3.1 Transmission of unacknowledged information.67
9.3.3.2 Reception of unacknowledged information .67
9.3.4 Unacknowledged release .67
9.4 Broadcast operation.68
9.4.1 Normal operation.68
9.4.1.1 Procedure in the Fixed radio Termination (FT).68
9.4.1.2 Procedure in the Portable radio Termination (PT).68
9.4.2 Expedited operation.68
9.4.2.1 Procedure in the Fixed radio Termination (FT).68
9.4.2.2 Procedure in the Portable radio Termination (PT).68

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ETS 300 175-4: October 1992
9.5 MAC layer interfaces.69
9.5.1 MC-SAP .69
9.5.1.1 C-plane overview .69
9.5.1.2 C-plane service data procedures.69
9.5.1.3 U-plane service data .70
9.5.2 MB-SAP .70
9.5.2.1 C-plane overview .70
9.5.2.2 C-plane service data procedures.70
9.5.2.3 U-plane service data .71
9.5.3 MA-SAP .71
9.5.3.1 Overview.71
9.5.3.2 Service data procedures .71
10 Management procedures .72
10.1 Lower Layer Management Entity (LLME).72
10.2 MAC connection management .72
10.2.1 MAC connection set-up.72
10.2.2 MAC connection release .73
10.2.3 MAC connection modification.73
10.2.4 MAC connection identifiers .74
10.2.4.1 Overview.74
10.2.4.2 Advanced MAC Connection Identifiers (AMCI) .74
10.2.4.3 Basic MAC Connection Identifiers (BMCI).75
10.2.4.4 MAC Connection Endpoint Identifier (MCEI).75
10.2.5 Selection of logical channel (C or C ) .75
S F
10.3 DLC C-plane (LAPC) management .76
10.3.1 Provision of link signature.76
10.3.2 Routing of connection oriented links .76
10.3.3 Routing of connectionless links .76
10.4 DLC U-plane (LUX) management.76
10.4.1 U-plane establishment.77
10.4.2 U-plane release.77
10.4.3 U-plane suspend and resume .77
10.5 Connection handover management .77
10.6 Connection ciphering management.78
10.6.1 Providing a key to the MAC layer.78
10.6.2 Starting and stopping the ciphering: .78
10.6.3 Connection handover .78
11 U-plane service characteristics .80
11.1 General .80
11.2 LU1 TRansparent UnProtected service (TRUP).80
11.3 LU2 Frame RELay service (FREL).81
11.3.1 General .81
11.3.2 Checksum operation .82
11.3.3 Segmentation and transmission class.82
11.3.4 Data transmission.83
11.3.4.1 Send side procedure.83
11.3.4.2 Receive side procedure.83
11.4 LU3 Frame SWItching service (FSWI).83
11.5 LU4 Forward Error Correction service (FEC).84
11.6 LU5 Basic Rate AdapTion service (BRAT).85
11.6.1 Overview .85
11.6.2 Protected service operation.86
11.6.2.1 General.86
11.6.2.2 Data buffering and initial rate adaption.86
11.6.2.3 Multi-channel set multiplexing.87
11.6.2.4 Segmentation of Multiplexed Data Units (MDU) .89
11.6.2.5 Frame sequencing and addition of control and fill octets.89
11.6.2.6 Frame transmission.90

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ETS 300 175-4: October 1992
11.6.3 Unprotected service operation. 91
11.6.3.1 General .91
11.6.3.2 Data buffering and initial rate adaption.91
11.6.3.3 Multi-channel set multiplexing.91
11.6.3.4 Segmentation of multiplexed data units.93
11.6.3.5 Frame transmission .93
11.7 LU6 Secondary Rate AdapTion service (SRAT).93
11.7.1 General . 93
11.8 LU16 ESCape Service (ESC). 94
11.8.1 General . 94
12 Frame structures for U-plane services.95
12.1 General.95
12.2 FU1 frame structure .95
12.2.1 General frame structure.95
12.2.2 FU1 buffering procedures.96
12.2.3 Minimum delay (speech) operation.96
12.2.4 Connection handover .96
12.2.5 Transmission order.97
12.3 FU2 frame structure .97
12.3.1 General frame structure.97
12.3.2 FU2 buffering procedures.97
12.3.3 Connection handover .98
12.3.4 Transmission order.98
12.4 FU3 frame structure .98
12.4.1 General frame structure.98
12.4.2 FU3 buffering procedures.99
12.4.3 Connection handover .99
12.4.4 Transmission order.99
12.5 FU4 frame structure .99
12.5.1 General frame structure.99
12.5.2 FU4 buffering procedures. 100
12.5.3 Connection handover . 101
12.5.4 Transmission order. 101
12.6 FU5 frame structure . 101
12.6.1 General frame structure. 101
12.6.2 FU5 buffering procedures. 102
12.6.3 Connection handover . 102
12.6.4 Transmission order. 102
12.7 FU6 frame structure . 103
12.7.1 General frame structure. 103
12.7.2 FU6 buffering procedures. 103
12.7.3 Connection handover . 104
12.7.4 Transmission order. 104
13 Elements of procedures and formats of fields for U-plane peer to peer communication. 105
13.1 General. 105
13.2 Address elements . 105
13.2.1 Address field format . 105
13.2.2 Address field parameters. 105
13.3 Length indicator elements . 106
13.3.1 Length indicator field format. 106
13.3.2 Length indicator field parameters. 106
13.4 Sequence number elements. 106
13.4.1 Send sequence number format. 106
13.4.2 Send sequence number parameters. 107
13.4.4 Receive sequence number parameters . 107
13.5 Fill elements . 107
13.5.1 Fill field format . 107

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ETS 300 175-4: October 1992
14 U-plane peer to peer procedures.108
14.1 General .108
14.2 Frame transmission principles .108
14.2.1 Sequence numbering .108
14.2.2 Acknowledgements.108
14.2.2.1 Sending acknowledgements.108
14.2.2.2 Receiving acknowledgements .108
14.2.3 Transmission classes.109
14.2.3.2 Class 1: no LU retransmission .109
X
14.2.3.3 Class 2: variable throughput LU retransmission .109
X
14.2.3.4 Class 3: fixed throughput LU retransmission.110
X
14.2.4 Operation parameter negotiation .110
14.3 Frame transmission procedures.110
14.3.1 General .110
14.3.2 Class 0 procedures . 110
14.3.2.1 Sending side procedure.111
14.3.2.2 Receiving side procedure .111
14.3.3 Class 1 procedures . 111
14.3.3.1 Sending side procedure.111
14.3.3.2 Receiving side procedure .111
14.3.4 Class 2 procedures . 112
14.3.4.1 Sending side procedure.112
14.3.4.2 Receiving side procedure .113
14.3.5 Class 3 procedures . 114
14.3.5.1 Sending side procedure.115
14.3.5.2 Receiving side procedure .116
Annex A (normative): System parameters.117
A.1 LAPC timer values.117
A.2 U-plane timer values .118
A.3 Constants .118
A.3.1 Retransmission counter (N250).118
A.3.2 Maximum number of CHO attempts (N251) .118
Annex B (informative): Checksum algorithms .119
B.1 Arithmetic conventions .119
B.2 Coding algorithm .119
B.3 Decoding algorithm.119
Annex C (informative): MAC connection states.120
Annex D (normative): Mapping of agreed channel rates to MCS sizes.121
D.1 Protected class operation .121
D.2 Unprotected class operation.122
History .123

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ETS 300 175-4: October 1992
Foreword
This European Telecommunication Standard (ETS) has been produced by the Radio Equipment and
Systems (RES) Technical Committee of the European Telecommunications Standards Institute (ETSI), and
was adopted, having passed through the ETSI standards approval procedure (Public Enquiry 23: 1991-09-
02 to 1991-12-27, Vote 22: 1992-05-25 to 1992-07-17).
Annexes A and D to this ETS are normative. Annexes B and C to this ETS are informative.
Further details of the DECT system may be found in ETSI Technical Reports ETR 015, [16], and ETR 043
[15], and also in draft ETSI Technical Report: "Digital European Cordless Telecommunications System
description document" [17].
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ETS 300 175-4: October 1992
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ETS 300 175-4: October 1992
1 Scope
This part of the Digital European Cordless Telecommunications (DECT) Common Interface specifies the
Data Link Control (DLC) layer. The Data Link Control layer is Part 4 of the DECT Common Interface
standard and layer 2b of the DECT protocol stack.
�˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜´˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜¿
‡  Network layer  ‡  Network layer  ‡
‡   C-plane   (3)   U-plane   ‡
†††††††††††††††††††††††††††††††††††††††††
†   DLC layer   †   DLC layer   †
†   C-plane   (2b)  U-plane   †
†††††††††††††††††††††††††††††††††††††††††
‡        MAC layer        ‡
‡         (2a)         ‡
ˆ˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜·
‡       Physical layer      ‡
‡         (1)         ‡
�˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜˜�
Two planes of operation are specified for this data link control (sub)layer. These planes are called the C-
plane (Control plane) and the U-plane (User plane).
The C-plane is mostly concerned with the DECT signalling aspects. It provides a reliable point-to-point
service that uses a link access protocol to offer error protected transmission of network layer messages.
The C-plane also provides a separate point-to-multipoint (broadcast) service (Lb).
The U-plane is only concerned with end-to-end user information. This plane contains most of the application
dependent procedures of DECT. Several alternative services (both circuit-mode and packet-mode) are
defined as a family of independent entities. Each service provides one or more point-to-point U-plane data
links, where the detailed characteristics of those links are determined by the particular needs of each
service. The defined services cover a wide range of performance, from "unprotected with low delay" for
speech applications to "highly protected with variable delay", for local area network applications.
This part of the standard uses the layered model principles and terminology as described in CCITT
Recommendations X.200 [23] and X.210 [24].

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ETS 300 175-4: October 1992
2 Normative references
This European Telecommunications Standard (ETS) incorporates, by dated or undated reference,
provisions from other publications. These normative references are cited at the appropriate places in the
text and the publications are listed hereafter. For dated references, subsequent amendments to, or
revisions of, any of these publications apply to this ETS only when incorporated in it by amendment or
revision. For undated references the latest edition of the publication referred to applies.
[1] ETS 300 175-1: "Radio Equipment and Systems (RES); Digital European
Cordless Telecommunications (DECT) Common Interface Part 1: Overview".
[2] ETS 300 175-2: "Radio Equipment and Systems (RES); Digital European
Cordless Telecommunications (DECT) Common Interface Part 2: Physical layer".
[3] ETS 300 175-3: "Radio Equipment and Systems (RES); Digital European
Cordless Telecommunications (DECT) Common Interface Part 3: Medium
access control layer".
[4] ETS 300 175-4: "Radio Equipment and Systems (RES); Digital European
Cordless Telecommunications (DECT) Common Interface Part 4: Data link
control layer".
[5] ETS 300 175-5: "Radio Equipment and Systems (RES); Digital European
Cordless Telecommunications (DECT) Common Interface Part 5: Network
layer".
[6] ETS 300 175-6: "Radio Equipment and Systems (RES); Digital European
Cordless Telecommunications (DECT) Common Interface Part 6: Identities and
addressing".
[7] ETS 300 175-7: "Radio Equipment and Systems (RES); Digital European
Cordless Telecommunications (DECT) Common Interface Part 7: Security
features".
[8] ETS 300 175-8: "Radio Equipment and Systems (RES); Digital European
Cordless Telecommunications (DECT) Common Interface Part 8: Speech coding
and transmission".
[9] ETS 300 175-9: "Radio Equipment and Systems (RES); Digital European
Cordless Telecommunications (DECT) Common Interface Part 9: Public access
profile".
[10] Reserved.
[11] Reserved.
[12] I-ETS 300 176: "Radio Equipment and Systems (RES); Digital European
Cordless Telecommunications (DECT) Approval test specification".
[13] Reserved for future ETS version of [12].
[14] CEPT Recommendation T/SGT SF2 (89) 6/0 : "Draft Recommendation T/SF
Services and Facilities of Digital European Cordless Telecommunications".
[15] ETR 043: "Radio Equipment and Systems (RES); Digital European Cordless
Telecommunications (DECT) Common Interface Services and Facilities,
requirements specification".
[16] ETR 015: "Digital European Cordless Telecommunications Reference
Document".
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ETS 300 175-4: October 1992
[17] Draft ETSI Technical Report: "Digital European Cordless Telecommunications
System Description Document".
[18] ETR 042: "Radio Equipment and Systems (RES); Digital European Cordless
Telecommunication (DECT). A guide to the DECT features that influence the
traffic capacity and the maintenance of high radio link transmission quality,
including the results of simulations".
[19] Reserved for future DECT related document.
[20] Reserved.
[21] ETSI-GSM Technical Specification 04.06 (Version 3.6.0): "MS-BSS interface
data link layer specification".
[22] ISO/IEC Publication ISO.8073 (1988 (E)): "Information processing systems -
Open Systems Interconnection (OSI) - Connection oriented transport protocol
specification".
[23] CCITT Recommendation X.200 (1988): "Reference model of open systems
interconnection for CCITT applications".
[24] CCITT Recommendation X.210 (1988): "OSI layer service conventions".
[25]-[29] Reserved.
[30] CCITT Recommendation Q.920 (1988): "Digital subscriber signalling system no.
1 data link layer - general aspects".
[31] CCITT Recommendation Q.921 (1988): "Digital subscriber signalling system no.
1 data link layer".
[32] CCITT Recommendation V.32 (1988): "Error-correcting procedures for DCES
using asynchronous-to-synchronous conversion".
[33] CCITT Recommendation V.110 (1988): "Support of Data Terminal Equipment
(DTEs) with V-series type interfaces by an Integrated services digital network".
3 Definitions, symbols and abbreviations
Refer to ETS 300 175-1 [1] for the main listing of definitions, symbols and abbreviations. For the purposes
of this ETS the following definitions apply:
3.1 DLC Layer definitions
Bearer handover: the internal handover process provided by the Medium Access Control (MAC) layer,
whereby one MAC connection can modify its underlying bearers while maintaining the service provided to
the Data Link Control (DLC) layer.
NOTE: Bearer handover is slot based.
C-plane: the control plane of the DECT protocol stacks, which contains all of the internal DECT protocol
control, but may also include some external user information.
NOTE: The C-plane stack always contains protocol entities up to and including the network
layer.
Cluster: a logical grouping of one or more cells between which bearer handover is possible. A cluster
control function controls one cluster.

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ETS 300 175-4: October 1992
NOTE: Internal handover to a cell which is not part of the same cluster can only be done by
connection handover.
Connection handover: the internal handover process provided by the DLC layer, whereby one set of DLC
entities (C-plane and U-plane) can reroute data from one MAC connection to a second new MAC
connection, while maintaining the service provided to the network layer.
NOTE: Connection handover is DLC frame based.
ConnectionLess mode (C/L): a transmission mode that transfers one packet (one self contained unit) of
data from one source point to one (or more) destination points in a single phase.
NOTE: Connectionless transmissions require the peer-to-peer associations to be prearranged,
and the transmission is unacknowledged at that layer.
Connection Oriented mode (C/O): a transmission mode that transfers data from one source point to one
or more destination points using a protocol based on three phases: "set-up", "data transfer" and "release".
NOTE: Connection oriented
...