Information processing systems — Fibre Distributed Data Interface (FDDI) — Part 2: Token Ring Media Access Control (MAC)

Describes the Media Access Control (MAC), the lower sublayer of the Data Link Layer (DLL), for Fibre Distributed Data Interface (FDDI). Intended for use in a high-performance multistation network with the protocol designed to be effective at 100 Mbit/s using a Token ring architecture and fibre optics as transmission medium over distance of several kilometers in extent. References: ISO 8802-2; 8802-5; 9314-1; 9314-3.

Systèmes de traitement de l'information — Interface de données distribuées sur fibre (FDDI) — Partie 2: Mécanisme d'accès au support de l'anneau à jeton (MAC)

General Information

Status
Published
Publication Date
17-May-1989
Current Stage
9093 - International Standard confirmed
Completion Date
13-Jul-2018
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ISO 9314-2:1989 - Information processing systems -- Fibre Distributed Data Interface (FDDI)
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INTERNATIONAL
IS0
STANDARD
9314-2
First edition
1989-05-01
Information processing systems - Fibre
Distributed Data Interface (FDDI) -
Part 2 :
Token Ring Media Access Control (MAC)
S ystemes de traitemen t de l’information - lntetiace de don&es distribu&es SW
fibre (FDDII -
Partie 2 : Mkcanisme d’accks au support de l’anneau ;i jeton (MAC)
Reference number
IS0 9314-Z : 1989 (E)

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IS0 9314-2 : 1989 (E)
Contents
Page
Foreword. iv
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
1 Scope. 1
2 Normative references . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
3 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
4 Conventions and abbreviations. . . . . . . . . . . . . . . . . . . . . 4
4.1 Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.2 Ab breviations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
6 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6 Services. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
6.1 MAC-to-LLC services. . . . . . . . . . . . . . . . . . . . . . . . 7
6.2 PHY-to-MAC services . . . . . . . . . . . . . . . . . . . . . . 11
6.3 MAC-to-SMT services . . . . . . . . . . . . . . . . . . . . . . 13
7 Facilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
7.1 Symbol set. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
7.2 Protocol Data Units . . . . . . . . . . . . . . . . . . . . . . . . 23
7.3 Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
7.4 Timers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
7.6 Frame counts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
0 IS0 1989
All rights reserved. No part of this publication may be reproduced or utilized in any form or by any
means, electronic or mechanical, including photocopying and microfilm, without permission in
writing from the publisher.
International Organization for Standardization
Case postale 56 l CH-1211 Geneve 20 l Switzerland
Printed in Switzerland
ii

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IS0 9314-2 : 1989 (E)
8 Operation. . 35
8.1 Overview. . 35
8.2 Structure . 40
8.3 Receiver . 41
8.4 Transmitter . 48
Tables
43
Table 1 Interpretation of FC field .
Figures
6
Figure 1 Token ring configuration example .
57
Figure 2 MAC receiver state diagram .
59
Figure 3 MAC transmitter state diagram .
Annexes
Annex A Addressing hierarchical structuring
........ 61
for locally-administered addresses.
61
A.1 General structure. .
A.2 Group addressing modes. . . . . . . . . . . . . . . . . . 62
Annex B Frame Check Sequence. . 63
63
B.l Description .
64
B.2 Generation of the FCS .
64
B.3 Checking the FCS. .
65
B.4 Implementation. .
65
B.5 Related standards. .
Figure B.l FCS implementation example . 66
. . .
III

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IS0 9314-2 : 1989 (E)
Foreword
IS0 (the International Organization for Standardization) is a worldwide federation of
national standards bodies (IS0 member bodies). The work of preparing International
Standards is normally carried out through IS0 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, govern-
mental and non-governmental, in liaison with ISO, also take part in the work.
Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the IS0 Council. They are approved in accordance with IS0 procedures requiring at
least 75 % approval by the member bodies voting.
International Standard IS0 9314-2 was prepared by Technical Committee ISO/TC 97,
lnforma tion processing systems.
IS0 9314 consists of the following parts, under the general title information processing
systems - Fibre Distributed Data Interface (FDDI) -
-
Part 1: Token Ring Physical Layer Protocol (PHY)
-
Part 2: Token Ring Media Access Control (MAC)
-
Part 3 : Token Ring Physical Layer, Medium Dependent (PMD)
iv

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IS0 9314-2 : 1989 (E)
Introduction
This part of IS0 9314 on the FDDI media access control is
intended for use in a high-performance multistation network.
This
protocol is designed to be effective at 100 Mbit/s using a Token
ring architecture and fibre optics as the transmission medium
over distances of several kilometres in extent.
V

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INTERNATIONAL STANDARD IS0 9314-2 : 1989 (E)
Information processing systems - Fibre Distributed Data
Interface (FDDI) -
Part 2:
Token Ring Media Access Control (MAC)
1 scope
This part of IS0 9314 specifies the Media Access Control (MAC), the lower sublayer of the
Data Link Layer (DLL), for Fibre Distributed Data Interface (FDDI).
FDDI provides a high-bandwidth (100 Mbit/s), general-purpose interconnection among computers
and peripheral equipment using fibre optics as the transmission medium in a ring configuration.
FDDI can be configured to support a sustained transfer rate of approximately 80 Mbit/s (10
Mbyte/s). It may not meet the response time requirements of all unbuffered high speed
devices. FDDI establishes the connection among many stations distributed over distances of
several kilometres in extent. Default values for the FDDI were calculated to accommodate
rings of up to 1 000 physical links and a total fibre path length of 200 km (typically
100 km of dual fibre cable).
corresponding to 500 stations and
FDDI consists of
(a) A Physical Layer (PL), which provides the medium, connectors, optical bypassing, and
driver/receiver requirements. PL also defines encode/decode and clock requirements as
required for framing the data for transmission on the medium or to the higher layers of
the FDDI. For purposes of this part of 9314, references to the PL are made in terms of
the Physical Layer entity designated PHY.
(b) A Data Link Layer (DLL), which is divided into two sublayers:
(1) A Media Access Control (MAC) which provides fair and deterministic access to
and generation and verification of frame check
the medium, address recognition,
sequences. Its primary function is the delivery of frames, including frame insertion,
repetition, and removal. The definition of MAC is contained in this part of IS0 9314.
(2) A Logical Link Control (LLC) which provides a common protocol to provide the
required data assurance services between MAC and the Network Layer.
(c) A Station Management (SMT)‘) which provides the control necessary at the station
level to manage the processes under way in the various FDDI layers such that a station
SMT provides services such as control of station
may work co-operatively on a ring.
initialization, configuration fault isolation and recovery, and scheduling
management,
procedures.
l) SMT will form the subject of a future part of IS0 9314.

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IS0 9314-2 : 1989 (E)
The MAC definition contained herein is designed to be as independent as possible from bo’
Concepts employed in IS0 8802-5, dealir
the physical medium and the speed of operation.
with Token Ring MAC operation have been modified to accommodate the higher FDDI speed
while retaining a similar set of services and facilities.
IS0 9314 specifies the interfaces, functions, and operations necessary to ensure interoperabilii
between conforming FDDI implementations. This part of IS0 9314 provides a function
description. Conforming implementations may employ any design technique that does nc
violate interoperability.
2 Normative references
The following standards contain provisions which, through reference in this text, constitui
provisions of this part of IS0 9314. At the time of publication, the editions indicated we1
valid. All standards are subject to revision, and parties to agreements based on this part (
IS0 9314 are encouraged to investigate the possibility of applying the most recent editions (
Members of IEC and IS0 maintain registers of currently val
the standards listed below.
International Standards.
---A Information processing systems - Local Area Networks - Part 2: Logic
IS0 8802-2:
Link Control (LLC). ’
---A Information processing systems - Local Area Networks - Part 5: Tokr
IS0 8802-5:
Ring Access Methob and Physical Layer specification.
IS0 9314-1: 1989, lnforma tion processing systems - Fibre Distributed Data Interface (FDDI)
Part t Token Ring Physical Layer Protocol (PHY).
IS0 9314-3: ---A Information processing systems - Fib/e Distributed Data Interface (FDDI)
Part 3: Token Rini Physical Layer, Medium Dependent (PMD).
3 Definitions
For the purposes of this part of IS0 9314, the following definitions apply:
3.1 asynchronous: A class of data transmission service whereby all requests for servic
contend for a pool of dynamically allocated ring bandwidth and response time.
The act of removing a Token from the ring for the purpose of Fran
3.2 capture:
transmission.
A process whereby one or more stations bid for the right to initialize tl
3.3 claim token:
ring.
3.4 entity: An active functional agent within an Open System Interconnection (OSI) layer
sublayer, including both operational and management functions.
3.5 flbre optics: The technology whereby optical signals from light-generating transmitters a
propagated through optical fibre waveguides to light-detecting receivers.
‘1 To be published.

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IS0 9314-2 : 1989 (E)
3.8 frame: A PDU transmitted between co-operating MAC entities on a ring, consisting of a
variable number of octets and control symbols.
3.7 Media Access Control (MAC): The Data Link Layer responsible for scheduling and routing
data transmissions on a shared medium Local Area Network (e.g., an FDDI ring).
3.8 nonrestrlcted token: A Token denoting the normal mode of asynchronous bandwidth
allocation, wherein the available bandwidth is time-sliced among all requesters.
3.9 octet: A data unit composed of eight ordered bits (a pair of data symbols).
3.10 Physlcal (PHY): The Physical Layer responsible for delivering a symbol stream produced
by an upstream MAC Transmitter to the logically adjacent downstream MAC Receiver in an
FDDI ring.
3.11 physical connection: The full-duplex physical layer association between adjacent physical
layer entities (in concentrators, repeaters, or stations) in an FDDI ring.
3.12 prlmltlve: An element of the service interface presented by an entity.
3.13 Protocol Data Unlt (PDU): The unit of data transfer between communicating peer layer
entities. It may contain control information, address information, data (e.g., an SDU from a
The FDDI MAC PDUs are Tokens and
higher layer entity), or any combination of the three.
Frames.
3.14 receive: The action of a station in accepting a Token, Frame, or other symbol sequence
from the incoming medium.
3.15 repeat: The action of a station in receiving a Token or Frame from the adjacent
upstream station and simultaneously sending it to the adjacent downstream station. The FDDI
MAC may repeat received PDUs (Tokens and Frames), but does not repeat the received
symbol stream between PDUs. While repeating a Frame, MAC may copy the data contents
and modify the control indicators as appropriate.
3.16 restricted token: A Token denoting a special mode of asynchronous bandwidth allocation,
wherein the bandwidth available for the asynchronous class of service is dedicated to a single
extended dialogue between specific requesters.
3.17 ring: Two or more stations connected by a physical medium wherein information is
passed sequentially between active stations, each station in turn examining or copying and
repeating the information, finally returning it to the originating station.
3.18 Service Data Unit (SDU): The unit of data transfer between a service user and a
service provider.
3.19 services: A set of functions provided by one OSI layer sublayer entity, for use by a
higher layer or sublayer entity or by management entities.
3.20 station:
An addressable logical and physical attachment in a ring, capable of transmitting,
receiving, and repeating information.
An FDDI station has one or more PHY entities, one or
more MAC entities, and one SMT entity.
3.21 Station Management (WIT): The supervisory entity within an FDDI station that monitors
and controls the various FDDI entities including PMD, MAC, and PHY.

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IS0 9314-2 : 1989 (E)
3.22 symbol: The smallest signalling element used by MAC, i.e., the PHY SDU. The symt:
set consists of 16 data symbols and 8 control symbols. Each symbol maps to a speci
sequence of five code bits as transmitted by the Physical Layer.
A class of data transmission service whereby each requester
3.23 synchronous:
preallocated a maximum band’width and guaranteed a response time not to exceed a speci
delay.
3.24 token: -An explicit indication of the right to transmit on a shared medium. On a Tok
Ring, the Token circulates sequentially through the stations in the ring. At any time, it may
held by zero or one station. FDDI uses two classes of Tokens: restricted and nonrestrictec
3.26 transmit:
The action of a station in generating a Token, Frame, or other symt
sequence and placing it on the outgoing medium.
4 Conventions and abbreviations
4.1 Conventions
The terms SMT, MAC, LLC, and PHY, when used without modifiers, refer specifically to t
local entities. The term LLC unless otherwise qualified refers to any local user of MAC da
services, other than SMT, including IS0 8802-2.
Low lines (e.g., requested-service-class) are used as a convenience to mark the name
signals, functions, etc., that might otherwise be misinterpreted as independent individual words
they were to appear in text.
The use of a period (e.g., MA,UNITDATA.request) is equivalent to the use of low lines exce
that a period is used as an aid to distinguish modifier words appended to an antecede
expression.
4.1.1 Addressing
my short address (MSA): %-bit Individual Address of this station (0 = Null).
(MLA): 48-bit Individual Address of this station (0 = Null). If a stati
my long address
does not implement 48-bit addressing then MLA-0.
short addresses: Set of l&bit station Addresses including MSA if not Null, the 16-l
Broadcast Address (all ones), and any other 16-bit Group Addresses recognized by this static
long addresses: Set of 48-bit Station Addresses including MLA if not Null, the 48-l
Broadcast Address (all ones), and any other 48-bit Group Addresses recognized by tl
station.
If a station does not implement 48-bit addressing, then MIA = 0.
When claiming the Token (i.e., the transmitter is in Claim Token state), if the station transml
with 16-bit addressing, then MLA = 0; conversely, if the station transmits with 48-l
addressing, then MSA = 0.

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IS0 9314-2 : 1989 (E)
4.1.2 Timing values and timers:
All timing values are expressed as the unsigned twos complements of the target, or remaining,
time in octets, i.e., the numerically greater magnitude represents the shortest time remaining.
This definition is for reference purposes only and does not prescribe the implementation,
These timing
except where these timing values appear in Protocol Data Units on the ring.
values are not ail used simultaneously in the state machines; consequently, the implementation
need not materialize- them when they are not needed.
For the purpose of the description contained in this part of IS0 9314, ail timers are assumed
to be initialized with the unsigned twos complement of the target, or remaining, time in octets.
Timers are further assumed to count upward if enabled, expiring when an overflow occurs. Ail
These conventions are only
timer comparisons are expressed on the basis of elapsed time.
for the convenience of documenting this part of IS0 9314 and do not prescribe implementation.
4.2 Abbreviations
Error-Ct Count of reportable frame errors
Frame-Ct Count of ail frames received
TRT expirations (Token Lateness)
Late-Ct Count of
LostSt Count of PDUs detected as lost
Destination Address match in last received frame
A-Flag Indicates
C-Flag indicates successful copying of last received frame
E-Flag Indicates error detected in last received frame
H-Flag indicates Higher Source Address received
L-Flag indicates Lower Source Address received
M-Flag indicates My Source Address received
N-Flag indicates next station addressing
the Token-class of the last valid Token received was restricted
R-Flag Indicates
Maximum signal acquisition time
A-Max
Maximum ring latency time
D-Max
Maximum frame time
F-Max
station physical insertion time
I-Max Maximum
Transmitter Frame set-up time
L-Max Maximum
number of MAC entities allowed on the ring
M-Max Maximum
S-Min Minimum safety timing allowance
T-Bid-Rc Bidding TTRT received by this station in Claim Frames
T-Bid-TX Bidding TTRT transmitted in this station’s Claim Frames
TVini t Ring initialization time
T-Max Maximum TTRT to be supported by this station
T-Min Minimum TTRT to be supported by this station
Negotiated TTRT during Claim process (in receiver)
T-W
Operative TTRT for this station (in transmitter)
T-Opr
T-Pri Set of n priority Token rotation time thresholds
T,Pri( n) Element n of the set T-Pri
T-React Worst Case time to react to a station insertion or removal
Requested TTRT for this station’s synchronous traffic
T-Req
T-Resp Worst case time to recover a Token
THT Token-Holding Timer
TRT Token-Rotation Timer
TTRT Target Token Rotation Time
TVX Valid-Transmission Timer

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IS0 9314-2 : 1989 (E)
6 General description
A Token ring consists of a set of stations serially connected by a transmission medium
form a closed loop (see figure 1). information is transmitted sequentially, as a stream
symbols, from one active station to the next. Each station generally regenerates and repe
each symbol and serves as the means for attaching one or more devices to the ring for
purpose of communicating with other devices on the ring. A given station (the one that
access to the medium) transmits information on to the ring, where the information circula
from one station to the next.
The addressed destination station(s) copies the information a’
Finally, the station that transmitted the information effectively removes it from
passes.
ring.
A B
a b
R
++
-Physical Medium
A,B,C,D,E,F,G, . . . N - Ring Stations
a,b,c,d,e,f,g . . . n - Bypass Function
Ail stations are active except B (b illustrated in bypass mode)
Figure 1 -
Token ring configuration example
A station gains the right to transmit its information on to the medium when it detects a To:
passing on the medium. The Token is a control signal comprised of a unique symbol sequel
that circulates on the medium following each information transmission.
Any station, UI
detection of a Token, may capture the Token by removing it from the ring. The station n
then transmit one or more frames of information. At the completion of its informa’
transmission, the station issues a new Token, which provides other stations the opportunity
gain access to the ring.
A Token-holding timer, or equivalent means, limits the length of time a station may
(occupy) the medium before passing the Token.

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IS0 9314-2 : 1989 (E)
Multiple levels of priority are available for independent and dynamic assignment depending upon
The classes of service may be synchronous (typically
the relative class of service required.
used for applications such as real-time voice), asynchronous (typically used for interactive
applications), or immediate (used for extraordinary applications such as ring recovery). The
allocation of ring bandwidth occurs by mutual agreement among users of the ring.
Error detection and recovery mechanisms are provided to restore ring operation ih the event
that transmission errors or medium transients (e.g., those resulting from station insertion or
removal) cause the -access method to deviate from normal operation. Detection and recovery
for these cases utilizes a recovery function that is distributed among the stations attached to
the ring.
The media access method as specified herein is not intended to place constraints on the
logical link control or higher level protocols employed to effect data transfer.
6 Services
This clause specifies the services provided by MAC and the services required by MAC. The
intent is to allow higher-level protocol(s) (e.g., IS0 8802-2) to operate correctly with this MAC.
How many of the services described in this clause are chosen for a given implementation is
up to that implementer; however, a set of MAC services shall be supplied sufficient to satisfy
the higher level protocol(s) being used. The services as defined herein do not imply any
particular implementation, or any interface. Services described are
(a) MAC services provided to the local LLC entity, or other MAC users (indicated by
MA- prefix).
(b) Services required from the local PHY entity by MAC (indicated by PH- prefix).
(c) MAC services provided to the local SMT entity (indicated by SMJA- prefix).
6.1 MAC-to-LLC services
This subclause specifies the services provided by the Medium Access Control (MAC) to allow
the local LLC entity to exchange LLC service data units with peer LLC entities. These
services are also used for implementer frames. The following primitives are defined:
MA,UNiTDATA.request
MAJJNiTDATA.indication
MAJJNITDATA-STATUS.indication
MA,TOKEN.request
The description of each primitive includes a description of the information that is passed
between the LLC and MAC entities.
6.1.1 MAJJNiTDATA.request
This primitive defines the transfer of one or more Service Data Units (SDUs) from a local LLC
entity to a single peer LLC entity, or to multiple peer LLC entities in the case of group
addresses.

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IS0 9314-2 : 1989 (E)
6.1.1.1 Semantics of the primitive
MA,UNiTDATA.request
1
FC-value (I),
destination-address (I),
M-SW (I),
requested-service-class (I),
stream (I),
FLvalue (2),
destination-address (2),
LSDU (21,
requested-service-class (2),
stream (2),
.
I-C-value (n),
destination-address (n),
M-SW (n),
requested-service-class (n),
stream (n),
Token-class
1
Each set of FC-value, destination-address, MBSDU, requested-service-class and strea
parameters specifies one frame for transmission and is referred to as a subrequest.
The FC-value parameter supplies the Frame Control ( FC) field to be transmitted as part 4
the frame.
an individual or a group MAC addres
The destination,-address parameter may specify either
It shall contain sufficient information to create the DA (Destination Address) field that
Address length is determined by the L bit of the associate
included in the frame by MAC.
FC-value parameter (see 7.3.3).
Each M-SDU parameter specifies an LLC service data unit as received at the MAC interfac
to be transmitted by MAC. There is sufficient information associated with the MBSDU fc
MAC to determine the length of the service data unit. Associated with each MBSDU is
requested-service-class parameter.
Requested-service-class may be either Synchronous or Asynchronous. if asynchronous, tt
requested-Token-class and the priority level may optionally be specified.
Stream is a parameter that, if set, shall cause multiple MBSDUs to be transmitted as a rest
of the MAJJNiTDATA.request. Stream, when reset, indicates that this MBSDU is the last or
associated with this MA,UNiTDATA.request. The frames shall be transmitted in the ordc
presented by this primitive regardless of the associated requested-service-class. if TF
(Token-Rotation Timer) has expired (Late-Ct not= 0) or if a frame is encountered that cannc
be transmitted because of its associated requested-service-class and the current value (
THT (Token-Holding Timer), then transmission is terminated and a Token is issued as define
by the Token-class parameter. A MAJJNITDATA-STATUS.indication is subsequently returns
to LLC. if the transmission-status is successful, MAC may initiate transmission of tt
remaining frames on the next permitted access opportunity or, alternatively, MAC may requil
reissuance of a new MAJNiTDATA.request.

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IS0 9314-2 : 1989 (E)
Token-class specifies the class of Token that MAC shall issue following transmission of the
associated SDUs (i.e., at the end of the request), if no other request is pending that can be
r
honoured. With requests for synchronous service the Token-class shall be the Token-class
that was captured; with requests for asynchronous service it may be either restricted or
nonrestricted. If no SDUs were specified by the MAJJNiTDATA.request, then MAC shall
immediately issue the requested class of Token.
6.1.1.2 When generated
This primitive is generated by the local LLC entity whenever data is to be transferred to a
This may be in response to a
peer LLC entity or entities or a Token is to be generated.
request from higher layers of protocol or from data generated internally to LLC.
6.1.1.3 Effect of receipt
The receipt of this primitive shall cause MAC to append ail MAC-specific fields, including DA,
SA (Source Address), and any fields that are unique to the medium access method, and pass
the properly formed frames to the lower layers of protocol for transfer to peer MAC entity or
entities.
- This primitive is the normal means of requesting the transfer of data. The capture of
NOTE
a Token is implicit in this primitive and therefore it is not necessary to issue an
MA-TOKEN.request primitive in conjunction with it.
6.1.2 MAJJNiTDATA.indication
This primitive defines the transfer of data from MAC to the local LLC entity.
6.1.2.1 Semantics of the primitive
MA,UNiTDATA.indication
(
FC-value,
destination-address,
source-address,
MBSDU,
reception-status
1
The FC-value parameter specifies the value of the frame’s FC (Frame Control) field. The
destination-address parameter may be either an individual or a group address as specified by
the DA field of the incoming frame. The source-address parameter is an individual address
as specified by the SA field of the incoming frame. The M-SDU parameter shall specify the
MAC service data unit as received by the local MAC entity.
The reception-status parameter indicates the success or failure of the incoming frame. it
consists of the following elements:
(a) Frame validity: FR,GOOD, FLBAD
If a FR-BAD is reported, the reason for the error shall also be reported. The reason shall
be one of the following:
(1) Invalid FCS: Calculated FCS (Frame Check Sequence) does not match the
received FCS

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IS0 9314-2 : 1989 (E)
(2) Length Error: The frame did not have a valid data length
(3) Internal Error: An internal error has occurred that prevents MAC fro
transferring to LLC a frame that has been acknowledged by the setting of the
(address recognized) and C (frame copied) indicators.
(b) Frame Status:
The received E (error detected), A, C, and, optionally, any other indicator values.
6.1.2.2 When generated
The MAJJNlTDATA.indication primitive shall be generated by MAC to indicate to the local LL
entity the arrival of an LLC frame addressed to this station.
6.1.2.3 Effect of receipt
The effect of receipt of this primitive by the LLC entity is not specified.
6.1.3 MAJJNITDATA-STATUS.lndlcatlon
This primitive shall provide an appropriate response to MAJNITDATA.request primitiv
signifying the success or failure of the request.
6.1.3.1 Semantics of the primitive
MAJNITDATA-STATUS.indication
(
number-of-SDUs,
transmission-status,
provided-service-class
1
The number-of-SDUs parameter reports the number of MBSDUs transmitted on a giw
access opportunity as a result of this request.
The transmission-status parameter shall be used to pass information back to the IOC
requesting LLC entity. It shall be used to indicate the success or fai ure of the previor
associated MA,UNITDATA.request. If the MA,UNITDATA.request primitive
specified more th;
one MBSDU, then the transmission-status parameter may apply to all of t re SDUs transmitte
indicating if all were acknowledged, via the A and C indicators, by a peer MAC entity. In th
case, the resolution of the transmission-status is implementer defined.
The provided-service-class parameter specifies the service class that VI as provided for tt
transfer.
6.1.3.2 When generated
This primitive shall be generated by MAC in response to an MAJJNITDATA.request primitic
from the local LLC entity.
6.1.3.3 Effect of receipt
The effect of receipt of this primitive by LLC
...

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