ISO 21806-6:2020

INTERNATIONAL ISO
STANDARD 21806-6
First edition
2020-09
Road vehicles — Media Oriented
Systems Transport (MOST) —
Part 6:
Data link layer
Véhicules routiers — Système de transport axé sur les médias —
Partie 6: Couche de liaison de données
Reference number
©
ISO 2020
© ISO 2020
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ii © ISO 2020 – All rights reserved

Contents Page
Foreword .vi
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 3
4.1 Symbols . 3
4.2 Abbreviated terms . 3
5 Conventions . 4
6 DLL — Service interface to upper layers . 4
6.1 DLL — Overview . 4
6.2 DLL — Data type definitions . 4
6.3 DLL — Parameters . . 5
6.3.1 DLL — Parameters – DLL to TL/NL . 5
6.3.2 DLL — Parameters – TL/NL to DLL . 6
6.3.3 DLL — Parameters – DLL to TL/NL and TL/NL to DLL . 8
6.4 DLL — Event indications and action requests .10
6.4.1 DLL — L_EVENT.INDICATE .10
6.4.2 DLL — L_NODE_POSITION.INDICATE .10
6.4.3 DLL — L_MAXIMUM_NODE_POSITION.INDICATE .10
6.4.4 DLL — L_ACTION.REQUEST .10
6.4.5 DLL — L_NETWORK_STARTUP.REQUEST .11
6.4.6 DLL — L_SET_GROUP_ADDRESS.REQUEST .11
6.4.7 DLL — L_SET_NODE_ADDRESS.REQUEST .11
6.4.8 DLL — L_SET_EUI_48.REQUEST .11
6.4.9 DLL — L_SET_TRANSMISSION_ATTRIBUTES.REQUEST.12
6.5 DLL — Control Data .12
6.5.1 DLL — L_CONTROL_DATA.RECEIVE .12
6.5.2 DLL — L_CONTROL_DATA.CONFIRM .12
6.5.3 DLL — L_CONTROL_DATA.SEND .13
6.6 DLL — Packet data .13
6.6.1 DLL — 16-bit addressing .13
6.6.2 DLL — 48-bit addressing .14
6.7 DLL — Streaming data .15
6.7.1 DLL — L_ALLOCATE.INDICATE .15
6.7.2 DLL — L_DEALLOCATE.INDICATE .15
6.7.3 DLL — L_CONNECT.INDICATE .16
6.7.4 DLL — L_DISCONNECT.INDICATE .16
6.7.5 DLL — L_SOURCE_DROP.INDICATE .16
6.7.6 DLL — L_STREAMING_DATA.RECEIVE .17
6.7.7 DLL — L_ALLOCATE.REQUEST .17
6.7.8 DLL — L_DEALLOCATE.REQUEST .17
6.7.9 DLL — L_CONNECT.REQUEST .18
6.7.10 DLL — L_DISCONNECT.REQUEST .18
6.7.11 DLL — L_STREAMING_DATA.SEND .18
7 DLL — Network frame .18
7.1 DLL — General .18
7.2 DLL — Administrative area .20
7.3 DLL — Source data area .20
7.4 DLL — Indicators .21
8 DLL — Channels .21
8.1 DLL — Allocation channel .21
8.1.1 DLL — General .21
8.1.2 DLL — Allocation frame structure .21
8.1.3 DLL — Common allocation channel related subjects .23
8.1.4 DLL — Allocation channel related subjects for the TimingMaster .24
8.1.5 DLL — Allocation channel related subjects for a TimingSlave .25
8.1.6 DLL — De-allocating . .27
8.1.7 DLL — Source-drop recognition .27
8.1.8 DLL — Error handling .28
8.2 DLL — Control channel .30
8.2.1 DLL — General .30
8.2.2 DLL — Control frame structure .31
8.3 DLL — Protected system channel .31
8.3.1 DLL — General .31
8.3.2 DLL — Protected system frame structure .32
8.4 DLL — Timestamp channel .34
8.4.1 DLL — General .34
8.4.2 DLL — Timestamp frame structure .34
8.4.3 DLL — Behaviour .35
8.5 DLL — Packet channel .35
8.5.1 DLL — General .35
8.5.2 DLL — Packet frame structure .36
8.5.3 DLL — Ethernet data frame structure .37
8.5.4 DLL — Short packet frame or short Ethernet data frame .38
8.6 DLL — Synchronous channel .38
8.6.1 DLL — General .38
8.6.2 DLL — Synchronous frame structure .38
8.7 DLL — Isochronous channel .38
8.7.1 DLL — General .38
8.7.2 DLL — Isochronous frame structure .38
8.8 DLL — Channel frame delay .39
9 DLL — Flow control.41
9.1 DLL — Pre-emptive acknowledge byte . .41
9.2 DLL — Early ending .41
9.3 DLL — Low-level retries .42
10 DLL — Arbitration .42
10.1 DLL — General .42
10.2 DLL — Load-adaptive arbitration .43
10.2.1 DLL — General .43
10.2.2 DLL — Downstream arbitration .46
10.2.3 DLL — Downstream or upstream arbitration .47
10.2.4 DLL — Conditional upstream arbitration .48
10.3 DLL — Round-robin arbitration .48
10.3.1 DLL — Basics .48
10.3.2 DLL — Ensuring round-robin transmit order .50
10.3.3 DLL — Examples .50
11 DLL — Addressing .51
11.1 DLL — General .51
11.2 DLL — 16-bit address types .52
11.2.1 DLL — General .52
11.2.2 DLL — Free-up address .52
11.2.3 DLL — Logical node address .52
11.2.4 DLL — Group address .52
11.2.5 DLL — Blocking broadcast address .53
11.2.6 DLL — Non-blocking broadcast address .54
11.2.7 DLL — Node position address .54
11.2.8 DLL — Debug address .54
iv © ISO 2020 – All rights reserved

11.3 DLL — 48-bit address types .55
12 DLL — Cyclic redundancy check (CRC) .55
12.1 DLL — General .55
12.2 DLL — 4-bit CRC .55
12.3 DLL — 16-bit CRC .56
12.4 DLL — 32-bit CRC .56
12.5 DLL — CRC usage . .56
12.6 DLL — CRC acknowledge .56
Annex A (normative) MOST network configurations .58
Annex B (normative) Frame indicators .65
Bibliography .68
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
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constitute an endorsement.
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expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 31,
Data communication.
A list of all parts in the ISO 21806 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
vi © ISO 2020 – All rights reserved

Introduction
The Media Oriented Systems Transport (MOST) communication technology was initially developed at
the end of the 1990s in order to support complex audio applications in cars. The MOST Cooperation was
founded in 1998 with the goal to develop and enable the technology for the automotive industry. Today,
1)
MOST enables the transport of high quality of service (QoS) audio and video together with packet data
and real-time control to support modern automotive multimedia and similar applications. MOST is a
function-oriented communication technology to network a variety of multimedia devices comprising
one or more MOST nodes.
Figure 1 shows a MOST network example.
Figure 1 — MOST network example
The MOST communication technology provides
— synchronous and isochronous streaming,
— small overhead for administrative communication control,
— a functional and hierarchical system model,
— API standardization through a function block (FBlock) framework,
— free partitioning of functionality to real devices,
— service discovery and notification, and
[4]
— flexibly scalable automotive-ready Ethernet communication according to ISO/IEC/IEEE 8802-3 .
MOST is a synchronous time-division-multiplexing (TDM) network that transports different data types
on separate channels at low latency. MOST supports different bit rates and physical layers. The network
clock is provided with a continuous data signal.
1) MOST® is the Registered Trademark of Microchip Technology Inc. This information is given for the convenience
of users of this document and does not constitute an endorsement by ISO.
Within the synchronous base data signal, the content of multiple streaming connections and control
data is transported. For streaming data connections, bandwidth is reserved to avoid interruptions,
collisions, or delays in the transport of the data stream.
MOST specifies mechanisms for sending anisochronous, packet-based data in addition to control data
and streaming data. The transmission of packet-based data is separated from the transmission of
control data and streaming data. None of them interfere with each other.
A MOST network consists of devices that are connected to one common control channel and packet
channel.
In summary, MOST is a network that has mechanisms to transport the various signals and data streams
that occur in multimedia and infotainment systems.
The ISO standards maintenance portal (https:// standards .iso .org/ iso/ ) provides references to MOST
specifications implemented in today's road vehicles because easy access via hyperlinks to these
specifications is necessary. It references documents that are normative or informative for the MOST
versions 4V0, 3V1, 3V0, and 2V5.
The ISO 21806 series has been established in order to specify requirements and recommendations
for implementing the MOST communication technology into multimedia devices and to provide
conformance test plans for implementing related test tools and test procedures.
To achieve this, the ISO 21806 series is based on the open systems interconnection (OSI) basic reference
[1] [2]
model in accordance with ISO/IEC 7498-1 and ISO/IEC 10731 , which structures communication
systems into seven layers as shown in Figure 2. Stream transmission applications use a direct stream
data interface (transparent) to the data link layer.
viii © ISO 2020 – All rights reserved

Figure 2 — The ISO 21806 series reference according to the OSI model
The International Organization for Standardization (ISO) draws attention to the fact that it is claimed
that compliance with this document may involve the use of a patent.
ISO takes no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has assured ISO that he/she is willing to negotiate licences under
reasonable and non-discriminatory terms and conditions with applicants throughout the world. In
this respect, the statement of the holder of this patent right is registered with ISO. Information may be
obtained from the patent database available at www .iso .org/ patents.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights other than those in the patent database. ISO shall not be held responsible for identifying
any or all such patent rights.
INTERNATIONAL STANDARD ISO 21806-6:2020(E)
Road vehicles — Media Oriented Systems Transport
(MOST) —
Part 6:
Data link layer
1 Scope
This document specifies technical requirements related to the MOST data link layer functionality.
A MOST network is comprised of two or more nodes connected through a physical layer. The data link
layer functionality is provided by each node. On each network, all nodes are synchronised and one node
provides the system clock. This node is the TimingMaster, while all other nodes are TimingSlaves. The
timing configuration of the node (TimingMaster or TimingSlave) determines the tasks that need to be
performed on the data link layer.
The data link layer specifies the following subjects:
— the service interface to the network layer;
— the network frame, its areas and indicators;
— the different network channels;
— the different flow control mechanisms;
— the load-adaptive arbitration and the round-robin arbitration;
— the different addressing options;
— the different cyclic redundancy checks, their usage and the CRC acknowledge;
— the frame indicators.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 21806-1, Road vehicles — Media Oriented Systems Transport (MOST) — Part 1: General information
and definitions
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 21806-1 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
diagnosis flag
flag that determines whether diagnosis is active
3.2
END
indicator for the end of a channel frame
3.3
Ethernet frame
frame according to ISO/IEC/IEEE 8802-3
3.4
isochronous frame
frame that consists of isochronous data
3.5
new allocation flag
flag that is set for newly allocated bytes
3.6
packet frame
frame that transports packet data with 16-bit addressing
3.7
PREAMBLE
indicator for the start of the network frame
3.8
protected system channel
channel that transports network status information
3.9
ring lock flag
flag that is set when the TimingMaster locks onto the incoming data stream
3.10
START
indicator for the start of a channel frame
3.11
static master flag
flag that determines whether the TimingMaster continuously sends network frames
3.12
synchronous frame
frame that is synchronous to the network clock and consists of unformatted data
3.13
timestamp channel
channel that is used to transport a CRC-protected timestamp
3.14
WAIT
indicator that is used for different purposes
2 © ISO 2020 – All rights reserved

4 Symbols and abbreviated terms
4.1 Symbols
<.> range of bits, e.g. bit 7 to bit 0: <7:0>
... and so on
--- empty cell/undefined
N packet bandwidth control
PBC
N maximum value of packet bandwidth control
PBC_max
N remaining number of source data bytes per frame
SDBPFREST
N total number of administrative bytes per frame
TNABPF
N total number of bytes per frame
TNBPF
N total number of source data bytes per frame
TNSDBPF
4.2 Abbreviated terms
alloc allocation
Arb[X] 8-bit arbitration value
ARBVAL arbitration value
CACK CRC acknowledge
CF channel frame
CL connection label
CPos calculated position of the END indicator
CRC cyclic redundancy check
DLL data link layer
LSb least significant bit
MOST Media Oriented Systems Transport
MSb most significant bit
NC node counter (used in tables and figures)
NF network frame (used in tables and figures)
NOFFAD number of frames for auto deblock
PACK pre-emptive acknowledge
PDU protocol data unit
SDBPF source data bytes per frame
SOAF start of allocation frame
TM TimingMaster (used in figures)
TS TimingSlave (used in figures)
5 Conventions
[2]
This document is based on OSI service conventions as specified in ISO/IEC 10731 .
6 DLL — Service interface to upper layers
6.1 DLL — Overview
The DLL service interface defines the abstract interface to the OSI transport layer and network layer
[3]
(see ISO 21806-4 ).
Figure 3 shows the service interface to upper layers.
Figure 3 — Service interface to upper layers
6.2 DLL — Data type definitions
REQ 2.1 Service interface – DLL – Data type definitions
The data types shall be in accordance to:
4 © ISO 2020 – All rights reserved

REQ 2.1 Service interface – DLL – Data type definitions
— Enum: 8-bit enumeration;
— Unsigned Byte: 8-bit unsigned numeric value;
— Unsigned Word: 16-bit unsigned numeric value;
— EUI-48: 48-bit address value;
— Byte Array: sequence of 8-bit aligned data.
6.3 DLL — Parameters
6.3.1 DLL — Parameters – DLL to TL/NL
6.3.1.1 DLL — Overview
Table 1 provides an overview of the parameters that are used in the specified service interface and
passed from DLL to TL/NL.
Table 1 — Parameters passed from DLL to TL/NL
Parameter Data type Description
Network_Event Enum {Unlock, Lock, Lock_
An event that is reported to TL/NL.
Flag,
Network_Change_Event,
Shutdown_Flag,
MOST_Output_Off,
Network_Activity}
Node_Position Unsigned Byte
Node counter
Maximum_Position Unsigned Byte
Visible nodes
Transmission_Status Enum {Success, Buffer_Full,
Transmission status that is reported back
CRC_Error, Wrong_Target}
to the sender.
6.3.1.2 DLL — Network_Event
The Network_Event lists events that are used to notify TL/NL about changes in the DLL, which require
no additional information.
REQ 2.2 Service interface – DLL – Parameters – DLL to TL/NL – DLL – Network_Event
The Network_Event parameter shall be of data type Enum and shall use the values defined in Table 2.
Table 2 — Network_Event values
Enum value Description
Unlock
Unlock event occurred
Lock
Lock reached
Lock_Flag
Lock flag detected
Network_Change_Event
The visible nodes value that is distributed by the TimingMaster has changed.
Consequently, a network change event (NCE) is generated.
Shutdown_Flag
Shutdown flag detected
Network_Activity_End
Network activity ended
Network_Activity
Network activity detected
6.3.1.3 DLL — Node_Position
REQ 2.3 Service interface – DLL – Parameters – DLL to TL/NL – DLL – Node_Position
The Node_Position parameter shall be of data type Unsigned Byte and shall contain the node counter (NC)
value of the respective node.
6.3.1.4 DLL — Maximum_Position
REQ 2.4 Service interface – DLL – Parameters – DLL to TL/NL – DLL – Maximum_Position
The Maximum_Position parameter shall be of data type Unsigned Byte and shall contain the valid number of
nodes visible in the MOST network.
6.3.1.5 DLL — Transmission_Status
The Transmission_Status lists the possible outcomes of a transmission.
REQ 2.5 Service interface – DLL – Parameters – DLL to TL/NL – DLL – Transmission_Status
The Transmission_Status values shall be of data type Enum and shall contain the value specified according to
Table 3.
Table 3 — Transmission_Status values
Enum value Description
Success
The node is ready to receive and a valid CRC is received.
Buffer_Full
The node is not ready to receive.
CRC_Error
Incorrect CRC received.
Wrong_Target
There is no such target. The PACK and CACK bytes remain unaltered.
6.3.2 DLL — Parameters – TL/NL to DLL
6.3.2.1 DLL — Overview
Table 4 provides an overview of the parameters that are used in the specified service interface and
passed from TL/NL to DLL.
Table 4 — Parameters passed from TL/NL to DLL
Parameter Data type Description
Network_Request
Enum { A request from TL/NL
cmd_Set_Shutdown_Flag,
cmd_Set_Lock_Flag,
cmd_Clear_Lock_Flag,
cmd_MOST_Output_Off,
cmd_MOST_Output_On,
cmd_Emergency_Shutdown,
cmd_Open_Bypass,
cmd_Static_Master,
cmd_Ring_Lock
}
Network_Startup_Type
Enum { Determines how a node starts up.
TimingMaster,
TimingSlave
}
Number_Of_Retries Unsigned Byte
The number of low-level retries to perform on a
control frame.
Priority Unsigned Byte
The priority for a control frame
6 © ISO 2020 – All rights reserved

Table 4 (continued)
Parameter Data type Description
Group_Address Unsigned Word
A group address
Node_Address Unsigned Word
A logical node address
EUI_48 EUI-48
A 48-bit address
Bandwidth Unsigned Word
Required bandwidth
6.3.2.2 DLL — Network_Request
The Network_Request lists actions that may be requested from the DLL. These requests require no
additional information.
REQ 2.6 Service interface – DLL – Parameters – TL/NL to DLL – DLL – Network_Request
The Network_Request values shall be of data type Enum and shall use the value specified according to Table 5.
Table 5 — Network_Request values
Enum value Description
cmd_Set_Shutdown_Flag
Setting the shutdown flag requested. By default, the shutdown flag is not set.
cmd_Set_Lock_Flag
Setting the lock flag requested. By default, the lock flag is cleared.
cmd_Clear_Lock_Flag
Clearing the lock flag requested. By default, the lock flag is cleared.
cmd_MOST_Output_Off
Switching off the MOST output requested. By default, the MOST output is off.
cmd_MOST_Output_On
Switching on the MOST output requested. By default, the MOST output is off.
cmd_Emergency_Shutdown
Emergency shutdown requested. By default, emergency shutdown is not
active.
cmd_Open_Bypass
Opening the bypass requested. By default, the bypass is closed.
cmd_Static_Master
Static master mode requested. By default, the TimingMaster is in standard
TimingMaster mode.
cmd_Ring_Lock
Ring lock requested. By default, the TimingMaster is not locked.
6.3.2.3 DLL — Network_Startup_Type
The Network_Startup_Type lists the two different startup types, which can be chosen for the node.
REQ 2.7 Service interface – DLL – Parameters – TL/NL to DLL – DLL – Network_Startup_Type
The Network_Startup_Type values shall be of data type Enum and shall use the value specified according to
Table 6.
Table 6 — Network_Startup_Type values
Enum value Description
TimingMaster
For startup, configure the node as TimingMaster.
TimingSlave
For startup, configure the node as TimingSlave.
6.3.2.4 DLL — Number_Of_Retries
REQ 2.8 Service interface – DLL – Parameters – TL/NL to DLL – DLL – Number_Of_Retries
The Number_Of_Retries parameter shall be of data type Unsigned Byte and shall use the maximum
permissible number of low-level retries for a particular transmission.
6.3.2.5 DLL — Waiting_Period
REQ 2.9 Service interface – DLL – Parameters – TL/NL to DLL – DLL – Waiting_Period
The Waiting_Period parameter shall be of data type Unsigned Byte and shall use the waiting period
between low-level retries for a particular transmission.
6.3.2.6 DLL — Priority
REQ 2.10 Service interface – DLL – Parameters – TL/NL to DLL – DLL – Priority
The Priority parameter shall be of data type Unsigned Byte and shall use the priority for a particular
transmission.
6.3.2.7 DLL — Group_Address
REQ 2.11 Service interface – DLL – Parameters – TL/NL to DLL – DLL – Group_Address
The Group_Address parameter shall be of data type Unsigned Word and shall use the group address of the node.
6.3.2.8 DLL — Node_Address
REQ 2.12 Service interface – DLL – Parameters – TL/NL to DLL – DLL – Node_Address
The Node_Address parameter shall be of data type Unsigned Word and shall use the logical node address.
6.3.2.9 DLL — EUI_48
REQ 2.13 Service interface – DLL – Parameters – TL/NL to DLL – DLL – EUI_48
The EUI_48 parameter shall be of data type EUI-48 and shall use the MAC address of the node.
6.3.2.10 DLL — Bandwidth
REQ 2.14 Service interface – DLL – Parameters – TL/NL to DLL – DLL – Bandwidth
The Bandwidth parameter shall be of data type Unsigned Word and shall use the value to request the
allocation of the corresponding number of bytes in the network frame.
6.3.3 DLL — Parameters – DLL to TL/NL and TL/NL to DLL
6.3.3.1 DLL — Overview
Table 7 provides an overview of the parameters that are used in the specified service interface for both
directions.
Table 7 — Parameters used both ways
Parameter Data type Description
Media_Interface_ID Unsigned Word
An identifier for media data output or input
Length Unsigned Word
Length of the data field that is used in the same service
interface.
Data Byte Array
A data field, whose length is determined by the Length
parameter.
Session_ID Unsigned Word
A session identifier to correlate confirmations to send
operations.
Target_Address Unsigned Word
A 16-bit target address
Source_Address Unsigned Word
A 16-bit source address
8 © ISO 2020 – All rights reserved

Table 7 (continued)
Parameter Data type Description
Destination_MAC_Address EUI-48
A 48-bit target address
Source_MAC_Address EUI-48
A 48-bit source address
6.3.3.2 DLL — Media_Interface_ID
REQ 2.15 Service interface – DLL – Parameters – DLL to TL/NL and TL/NL to DLL – DLL –
Media_Interface_ID
The Media_Interface_ID parameter shall be of data type Unsigned Word and shall be used to
unambiguously identify a media interface as source or target of streaming data.
6.3.3.3 DLL — Length
REQ 2.16 Service interface – DLL – Parameters – DLL to TL/NL and TL/NL to DLL – DLL – Length
The Length parameter shall be of data type Unsigned Word and shall be used to provide the size of the data
field that is used in the same service interface.
6.3.3.4 DLL — Data
REQ 2.17 Service interface – DLL – Parameters – DLL to TL/NL and TL/NL to DLL – DLL – Data
The Data parameter shall be of data type Byte Array and shall be used as a wrapper for payload that requires
no interpretation in the context of the service interface that contains it.
6.3.3.5 DLL — Session_ID
REQ 2.18 Service interface – DLL – Parameters – DLL to TL/NL and TL/NL to DLL – DLL –
Session_ID
The Session_ID parameter shall be of data type Unsigned Word and shall be used to unambiguously identify
an instance of a control frame that is passed down. The session ID is used when determining the outcome of a
transmission attempt.
6.3.3.6 DLL — Target_Address
REQ 2.19 Service interface – DLL – Parameters – DLL to TL/NL and TL/NL to DLL – DLL –
Target_Address
The Target_Address parameter shall be of data type Unsigned Word and shall be used to fill the target ad-
dress field for 16-bit addressing for control data and packet data.
6.3.3.7 DLL — Source_Address
REQ 2.20 Service interface – DLL – Parameters – DLL to TL/NL and TL/NL to DLL – DLL –
Source_Address
The Source_Address parameter shall be of data type Unsigned Word and shall be used to fill the source
address field for 16-bit addressing for control data and packet data.
6.3.3.8 DLL — Destination_MAC_Address
REQ 2.21 Service interface – DLL – Parameters – DLL to TL/NL and TL/NL to DLL – DLL –
Destination_MAC_Address
The Destination_MAC_Address parameter shall be of data type EUI-48 and shall be used to fill the
destination address field for 48-bit addressing.
6.3.3.9 DLL — Source_MAC_Address
REQ 2.22 Service interface – DLL – Parameters – DLL to TL/NL and
...