EN 29314-1:1993
(Main)Information processing systems - Fibre Distributed Data Interface (FDDI) - Part 1: Token Ring Physical Layer Protocol (PHY) (ISO 9314-1:1989)
Information processing systems - Fibre Distributed Data Interface (FDDI) - Part 1: Token Ring Physical Layer Protocol (PHY) (ISO 9314-1:1989)
Informationsverarbeitungssysteme - Verteilte Datenschnittstelle mit Lichtwellenleitern (FFDI) - Teil 1: Protokoll für die Bitübertragungsschicht (PHY) (ISO 9314-1:1989)
Systèmes de traitements de l'information - Interface de données distribuées sur fibre (FDDI) - Partie 1: Protocole de la couche physique de l'anneau à jeton (ISO 9314-1:1989)
Information processing systems - Fibre Distributed Data Interface (FDDI) - Part 1: Token Ring Physical Layer Protocol (PHY) (ISO 9314-1:1989)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 29314-1:1997
01-december-1997
Information processing systems - Fibre Distributed Data Interface (FDDI) - Part 1:
Token Ring Physical Layer Protocol (PHY) (ISO 9314-1:1989)
Information processing systems - Fibre Distributed Data Interface (FDDI) - Part 1: Token
Ring Physical Layer Protocol (PHY) (ISO 9314-1:1989)
Informationsverarbeitungssysteme - Verteilte Datenschnittstelle mit Lichtwellenleitern
(FFDI) - Teil 1: Protokoll für die Bitübertragungsschicht (PHY) (ISO 9314-1:1989)
Systemes de traitements de l'information - Interface de données distribuées sur fibre
(FDDI) - Partie 1: Protocole de la couche physique de l'anneau a jeton (ISO 9314-
1:1989)
Ta slovenski standard je istoveten z: EN 29314-1:1993
ICS:
35.100.10 )L]LþQLVORM Physical layer
35.200 Vmesniška in povezovalna Interface and interconnection
oprema equipment
SIST EN 29314-1:1997 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 29314-1:1997
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SIST EN 29314-1:1997
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SIST EN 29314-1:1997
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SIST EN 29314-1:1997
INTERNATIONAL
IS0
STANDARD
9314-I
First edition
1989-04- 15
Information processing systems - Fibre
Distributed Data Interface (FDDI) -
Part 1 :
Token Ring Physical Layer Protocol (PHY)
S ystkmes de traitemen t de l’informa tion -
Interface de don&es distribuees sur
fibre (FDDl) -
Partie I : Protocole de la couche physique de l’anneau ;i jeton
Reference number
IS0 9314-1 : 1989 (E)
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SIST EN 29314-1:1997
ISO9314=1:1989(E)
Contents
Page
iv
..............................................................
Foreword
V
............................................................
Introduction
I
1 Scope .
2
.................................................
2 Normative references
2
..........................................................
3 Definitions
4
........................................
4 Conventions and abbreviations.
4
4.1 Conven~ons .
4
..................................................
4.2 Abbreviations.
4
..................................................
5 General description.
5
..........................................................
6 Services.
........................................... 6
6.1 PHY-to-MAC services.
9
............................................
PHY-to-PMD services
6.2
II
............................................
6.3 PHY-to-SMT services
14
7 Facilities .
14
7.1 Coding .
14
7.2 Symbolset .
I6
7.3 Linestates .
I8
8 Operation .
I8
................................................
8.1 Coding overview
............................................. I9
8.2 General organization
............................................. 23
8.3 Smoothing Function
@ 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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.................................................... 26
8.4 Repeat Filter
27
8.5 Ringlatency .
?a bles
7
Table I Symbol coding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figures
............................ 5
Figure I FDDI physical connection example.
............. 29
Figure 2 An example of a FDDI PHY functional block diagram
Figure 3 Smoother state diagram. . 30
.................................... 31
Figure 4 Repeat filter state diagram
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SIST EN 29314-1:1997
ISO9314=1:1989(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. IS0
collaborates closely with the International Electrotechnical Commission (IEC) on all
matters of electrotechnical standardization.
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-l 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 7 : Token Ring Physical Layer Protocol (PHY)
- Part 2: Token Ring Media Access Control (MAC)
- Part 3: Token Ring Physical Layer, Medium Dependent (PMD)
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ISO9314-1 A989 (E)
Introduction
This part of IS0 9314 on the FDDI physical layer protocol 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 kilometers in extent.
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SIST EN 29314-1:1997
IS0 9314-l : 1989 (E)
INTERNATIONAL STANDARD
Information processing systems - Fibre Distributed Data
Interface (FDDI) -
Part 1 I
Token Ring Physical Layer Protocol (PHY)
1 scope
This part of IS0 9314 specifies the Physical Layer Protocol (PHY), the upper sublayer of the
Physical Layer, for Fibre Distributed Data Interface (FDDI).
FDDI provides a high-bandwidth (100 Mbit/s), general-purpose interconnection among computers
FDDI can be
and peripheral equipment using fibre optics as the transmission medium.
configured to support a sustained transfer rate of approximately 80 Mbit/s (10 Mbyte/s). It
FDDI
may not meet the response time requirements of all unbuffered high-speed devices.
establishes connections among many stations distributed over distances of several kilometers in
extent. Default values for FDDI were calculated on the basis of 1 000 physical links and a
total fibre path length of 200 km (typically corresponding to 500 stations and 100 km of dual
fibre cable).
FDDI consists of:
(a) A Physical Layer (PL), which is divided into two sublayers:
(1) A Physical Medium Dependent (PMD), which provides the digital baseband
point-to-point Communication between stations in the FDDI network. The PMD
provides all services necessary to transport a suitably coded digital bit stream from
station to station. The PMD defines and characterizes the fibre-optic drivers and
receivers, medium-dependent code requirements, cables, connectors, power budgets,
optical bypass provisions, and physical-hardware-related characteristics. It specifies
the point of interconnectability for conforming FDDI attachments.
(2) A Physical Layer Protocol (PHY), which provides connection between the PMD
and the Data Link Layer.
PHY establishes clock synchronization with the upstream
code-bit data stream and decodes this incoming code-bit stream into an equivalent
symbol stream for use by the higher layers. PHY provides encoding and decoding
between data and control indicator symbols and code bits, medium conditioning and
initializing, the synchronization of incoming and outgoing code-bit clocks, and the
delineation of octet boundaries as required for the transmission of information to or
from higher layers. Information to be transmitted on the interface medium is encoded
by the PHY into a grouped transmission code. The definition of PHY is contained in
this part of IS0 9314.
(b) A Data Link Layer (DLL), which controls the accessing of the medium and the
generation and verification of frame check sequences to ensure the proper delivery of
valid data to the higher layers. DLL also concerns itself with the generation and
recognition of device addresses and the peer-to-peer associations within the FDDI
network. For the purpose of the PHY definition contained in this part of IS0 9314,
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IS0 9314-1 : 1989 (E)
references to DLL are made in terms of the Media Access Control (MAC) entity, which is
the lowest sublayer of DLL.
(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
work cooperatively on a ring. SMT provides services such as control of
may
configuration management, fault isolation and recovery, and scheduling procedures.
The definition of PHY as contained in this part of IS0 9314 is designed to be as independent
as possible from the actual physical medium.
IS0 9314 specifies the interfaces, functions, and operations necessary to ensure interoperability
between conforming FDDI implementations. This part of IS0 9314 is a functional description.
Conforming implementations employ any design technique that does not violate
may
interoperability.
2 Normative references
which, through reference in this text, constitute
The following standards contain provisions
provisions of this part of IS0 9314. At the time of publication, the editions indicated were
valid.
All standards are subject to revision, and parties to agreements based on this part of
IS0 9314 are encouraged to investigate the possibility of applying the most recent editions of
the standards listed below. Members of IEC and IS0 maintain registers of currently valid
International Standards.
- Fibre Distributed Data Interface (FDDI) -
IS0 9314-2: 1989, lnforma tion processing systems
Part 2: Token Ring Media Access Control (MAC).
IS0 9314-3: -9--*I, lnforma tion processing systems - Fibre Distributed Data Interface (FDDI) -
Part 3: Token Ring Physical Layer, Medium Dependent (PMD).
3 Definitions
For the purposes of this part of IS0 9314, the following definitions apply:
3.1 code bit: The smallest signalling element used by the Physical Layer for transmission on
the medium.
3.2 code group: The specific sequence of five code bits representing a DLL symbol.
3.3 concentrator: A node on the FDDI ring, which in turn provides connections for additional
conforming FDDI stations so that they may communicate with other attachments to the FDDI
ring. A concentrator has two Physical Layer entities and may or may not have one or more
Data Link Layer entities.
3.4 Connection Management (WIT): That portion of the Station Management (SMT) function
removal, and connection of PHY and MAC entities within a
that controls network insertion,
station.
‘) SMT will form the subject of a future part of IS0 9314.
2, To be published.
2
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3.5 entity: An active element within an Open System Interconnection (OSI) layer, or sublayer;
or SMT, in a specific station.
3.6 flbre optics: A technology whereby signals are transmitted over an optical waveguide
medium through the use of light-generating transmitters and light-detecting receivers.
3.7 frame: A Protocol Data Unit transmitted between cooperating MAC entities on a ring,
consisting of a variable number of octets.
3.8 nonreturn to zero (NRZ): A technique in which a polarity level high, or low, represents a
logical '1' (one), or ‘0’ (zero).
3.9 nonreturn to zero Invert on ones (NRZI): A technique in which a polarity transition
represents a logical ‘1’ (one). The absence of a polarity transition denotes a logical ‘0’ (zero).
3.10 physical connection: The full-duplex physical layer association between adjacent PHY
entities (in concentrators, repeaters, or stations) in an FDDI ring, i.e., a pair of Physical Links.
3.11 physical link: The simplex path (via PMD and attached medium) from the transmit function
of one PHY entity to the receive function of an adjacent PHY entity (in concentrators,
repeaters, or stations) in an FDDI ring.
3.12 primitive: An element of the services provided by one entity to another.
3.13 Protocol Data Unit (PDU): Info lmation delivered as a unit between peer entities that may
contain control information, address information and data (e.g., an Service Data Unit from a
higher layer).
3.14 receive: The action of a stati{ frame, token, or control sequence from
on of accepting a
the medium.
3.15 repeat: The act of a station in receiving a code-bit stream (e.g., frame or token) from an
The station repeating the
upstream station and placing it on the medium to the next station.
code-bit stream examines it and may copy it into a buffer and modify control indicators as
appropriate.
3.16 ring: Two or more stations in which information is passed sequentially between active
stations, each station in turn examining or copying the information, finally returning it to the
originating station.
3.17 Service Data Unit (SDU): The unit of data transfer between a service user and a service
provider.
3.18 services: The services provided by one entity to a higher entity or to SMT
i
3.19 station: An addressable logical and physical node on a ring capable of transmitting,
repeating, and receiving information.
3.20 Station Management (SMT): The entity within a station on the ring that monitors station
activity and exercises overall appropriate control of station activity.
3.21 symbol: The smallest signalling element used by the Data Link Layer (DLL). The symbol
set consists of 16 data symbols and 8 control symbols. Each symbol corresponds to a
specific sequence of code bits (code group) to be transmitted by the Physical Layer.
3
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ISO9314-1 : 1989 0
3.22 transmit: The action of a station that consists of generating a frame, token, or control
sequence, and placing it on the medium to the next station.
4 Conventions and abbreviations
4.1 Conventions
The terms SMT, MAC, PMD and PHY, when used without modifiers, refer specifically to the
local entities.
Low lines (e.g., control-action) are used as a convenience to mark the name of signals,
rerwise be misinterpreted as independent individual words
functions, or the like, which might otb
if they were to appear in text.
The use of a period (e.g., PHJNI’ TDATA.request) is equivalent to the use of a low line
except that a period is used as an aid to distinguish modifier words appended to an
antecedent expression.
4.2 Abbreviations
ALS Active-Line-state
HLS Halt-Line-state
ILS Idle-Line-state
MLS Master-Line-state
NLS Noise-Line-state
Quiet-Line-state
QLS
NRZ Non Return to Zero
NRZI Non Return to Zero, Invert on Ones
PI Primary Input
PO Primary Output
RCRCLK Receiver Recovery Clock
SI Secondary Input
so Secondary Output
Hi,Ct Current Smoother extension (in symbols) at 14-symbol threshold
LoJt Current Smoother extension (in symbols) at 120symbol threshold
Out-ct Number of symbols output in current Smoother state
T-Flag Indicates current frame can not be stripped
D-Max Maximum ring latency
Hi-Max Maximum smoothing capacity (in symbols) at 14-symbol threshold
Lo-Max Maximum smoothing capacity (in symbols) at 12-symbol threshold
P-Max Maximum number of Physical Layer entities
SD-Max Maximum starting delimiter delay contribution
SD-Min Minimum starting delimiter delay
6 General description
A ring network consists of a set of stations logically connected as a serial string of stations
Information is transmitted sequentially, as a
and transmission media to form a closed loop.
from one active station to the next. Each station
stream of suitably encoded symbols,
generally regenerates and repeats each symbol and serves as the means for attaching one or
more devices to the network for the purpose of communicating with other devices on the
network.
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ISO9314-1:1989(E)
The basic building block of an FDDI network is a Physical Connection as shown in figure 1. A
Physical Connection in the FDDI ring consists of the Physical Layers of two stations that are
A Primary
connected over the transmission medium by a Primary Link and a Secondary Link.
link consists of an output, called Primary Out (PO), of a Physical layer, communicating over a
Primary medium to the input, called Primary In (PI), of a second Physical Layer. The
Secondary link consists of the output, called Secondary Out (SO), of the second Physical
Layer communicating over a Secondary medium to the input, called Secondary In (SI), of the
first Physical Layer. Physical Connections may be subsequently logically connected within
nodes, via attached MACs or other means, to create the network.
SMT
An FDDI network consists of a theoretically unlimited number of connected stations.
and the correct internal station
establishes the physical connections between stations,
The method of actual physical
configuration, to create an FDDI network of logical rings.
attachment of stations to the FDDI network will vary and is dependent on specific application
requirements. The function of each station is implementer defined and is determined by the
specific application or site requirements.
Physical Connection
------------------I-- ------------I-------
PHJJNITDATAJndication
PHJJNITDATA.request PO; Primary Link 1 PI -
t i
/-
I I /-
PHJNITDATA.rndrcatron ~ ’ ’ l 1 PHY kl i Secondary Link iSO PHY LPHJJNlTDATA.request
1 I
I
Station #M i Station #N
----------------I----w- -J
= Primary Out PI = Primary In
PO
SI = Secondary In so = Secondary Out
Figure 1 - FDDI physical connection example
6 Services
This clause specifies the services provided by PHY. The services as defined in this clause
’ do not imply any particular implementation or any interface. Services described are:
(a) PHY services provided to the local MAC entity (indicated by PH- prefix)
rices required from the local PMD ent ty by PHY (indicated by PM- prefix)
(b) Serv
(c) PHY services provided to the local SMT entity (indicated by SM-PH- prefix)
Figure 2 shows the block diagram organization
of the FDDI Physical layer including the
separate functions, related signals and interfaces that it contains. The interfaces and signals
between the Physical Layer, the data link layer and Station Management are intended to be
logical rather than physical. Any other set of signals that causes the same physical behaviour
of the protocol is equally valid.
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IS0 9314-1 : 1989 0
6.1 PHY-to-MAC services
This subclause specifies the services supplied by PHY to allow the local MAC entity to
exchange PDUs with peer entities. Additional detail is provided in IS0 9314-2 on FDDI MAC
conditions that generate these primitives and MAC actions upon receipt of
concerning
PHY-generated primitives. The following primitives are defined:
PH-UNITDATA.request
PH-UNITDATA.indication
PH-UNlTDATA,STATUS.indication
PH-INVALID.indication
All primitives described in this clause are mandatory.
The description of each primitive includes a description of the information that shall be passed
between MAC and PHY.
each PH-UNITDATA.indication causes exactly one
These services shall be ‘synchronous’, e.g.,
Depending upon the current internal configuration of the station, the
PH-UNITDATA.request.
Although
PH-UNITDATArequest may be returned to the same PHY, or to a different PHY.
these services are primarily intended as a PHY-to-MAC interface, they also serve as a
PHY-to-PHY interface when repeating on a logical ring with no intervening MAC. In this case
the function of the Repeat Filter (see 8.4) is required somewhere in the repeat path within the
physical layer.
6.1.1 PH-UNITDATA.request
This primitive defines the transfer of data from MAC to PHY.
6.1.1.1 Semantics of the primitive
PH-UNITDATA.request
(
PH-Request (symbol)
1
The symbol specified by PH-Request (symbol) shall be one of the following:
J, K, T, R, S, I, n, H and optionally Q or V, where n is any of the sixteen data symbols
specified in Table 1.
6.1.1.2 When generated
MAC sends PHY one PH,lJNITDATA.request for each PH-UNITDATA.indication received from
PHY.
6.1.1.3 Effect of receipt
Upon receipt of this primitive the PHY entity shall encode and transmit the symbol. When the
PHY entity is ready to accept another PH-UNITDATArequest, it shall return to MAC a
PH-UNITDATA-STATUS.indication.
NOTE - The transmission of Q, H, or V does not occur on a PHJNITDATA.request from MAC.
However, when repeating in the physical layer, a PHJNITDATA.request of H is possible (and Q
or V in implementations in which the Repeat Filter function is located after the
PHJNITDATA.request interface).
6
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Symbol coding
Table 1 -
Assignment
Decimal Code Symbol
Group
Line State Symbols
00 00000 QUIET
Q
31 11111 I IDLE
04 00100 H HALT
Starting Delimiter
24 3 1st. of Sequential SD Pair
11000
17 10001 K 2nd. of Sequential SD Pair
Data Symbols
Hex Binary
0 0000
30 11110 0
09 1 1 0001
01001
20 10100 2 2 0010
21 10101 3 3 0011
10 01010 4 4 0100
5 0101
11 01011 5
14 01110 6 6 0110
15 01111 7 7 0111
18 10010 8 8 1000
19 10011 9 9 1001
A 1010
22 10110 A
1011
23 10111 B B
26 C C 1100
11010
27 D D 1101
11011
28 11100 E E 1110
29 11101 F F 1111
Ending Delimiter
13 01101 Used to Terminate the Data Stream
Control lndica tors
07
00111 Denoting Logical ZERO (Reset)
25 11001 Denoting Logical ONE (Set)
Invalid Code Assignments
01 00001 U or H These code patterns shall not be
02 U or H
00010 transmitted because they violate
03 00011 U consecutive code-bit zeros or duty
05 00101 U cycle requirements. Codes 01, 02, 08
06 00110 U and 16 shall however be interpreted
08 01000 U or H as Halt when received.
12 01100 U
16 10000 U or H
(12345) = sequential order of code-bit transmission.
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6.1.2 PHJJNITDATAJndication
This primitive defines the transfer of data from PHY to MAC.
6.1.2.1 Semantics of the primitive
PH-UNITDATA.indication
(
PH-Indication (symbol)
1
The symbol specified by PH-Indication (symbol) shall be one of the following: J, K, T, R, S, I,
n, H and optionally Q or V, where n is any of the sixteen data symbols specified in Table 1.
The indication of Q or V is not required in implementations where the Repeat Filter function is
located prior to the PH-UNITDATA.indication interface.
6.1.2.2 When generated
PHY shall send MAC a PH-UNITDATA.indication every time it decodes a symbol received from
PMD. This indication is sent once every symbol period.
6.1.2.3 Effect of receipt
MAC accepts a symbol from PHY, processes it, and
Upon the receipt of this primitive,
generates a corresponding PH-UNITDATA.request to PHY; also conveying the resulting output
symbol.
6.1.3 PH,UNITDATA,STATUS.indication’)
This primitive has local significance and shall provide an appropriate response to the
of a symbol specified by the
PH-UNITDATA.request primitive signifying the acceptance
PH-UNITDATA.request and willingness to accept another symbol.
6.1.3.1 Semantics of the primitive
PI-i-UNITDATA,STATUS.indication (
transmission-status
1
The transmission-status parameter shall be used to signify the transmission completion status.
6.1.3.2 When generated
in response to every
MAC PH-UNlTDATA,STATUS.indication
PHY shall send
The purpose of the PH-UNITDATA,STATUS.indication is to
PH-UNITDATA.request received.
synchronize the MAC data output with the data rate of the medium.
6.1.3.3 Effect of receipt
The effect of receipt of this primitive by MAC is not specified.
I) This primitive is not used by IS0 9314-Z on FDDI MAC.
8
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6.1.4 PHJNVALIDJndicatlon
This primitive is generated by PHY and asserted to MAC to indicate that the symbol stream
has been detected as invalid.
6.1.4.1 Semantics of the primitive
PHJNVALID.indication
(
PHJnvalid
1
The PH-Invalid parameter shall indicate that the symbol stream is invalid.
6.1.4.2 When generated
PHY shall generate this primitive whenever it detects a Quiet, Halt, Master, or
Noise-Line-State. In addition, PHY shall generate this primitive for input error conditions
detected by PHY (such as Elasticity Buffer errors) if the implementation does not report them
as Violation symbols in the PHJNITDATA.indication symbol stream.
6.1.4.3 Effect of receipt
The effect of receipt of this primitive by MAC is not specified.
6.2 PHY-to-PMD services
This subclause specifies the services provided at the interface between the PHY and the PMD
entities of the Physical layer, to allow PHY to exchange an NRZI code-bit stream with peer
Additional detail is provided in PMD concerning conditions that generate these
PHY entities.
primitives and PMD actions upon receipt of PHY-generated primitives.
The following primitives are defined:
PMJJNITDATA.request
PMJNITDATA.indication
PM-SIGNAL.indication
The description of each primitive includes a description of the information that is passed
between the PHY and PMD entities.
The implementation of the PHY to PMD interface is not specified. However, an exemplary
implementation of this interface is provided as an annex to IS0 9314-3.
6.2.1 PM,UNITDATA.request
This primitive defines the transfer of NRZI data from PHY to PMD.
6.2.1.1 Semantics of the primitive
PM,UNITDATA.request
(
PM-Request (NRZI code)
1
The data conveyed by PM-Request shall be a continuous NRZI code (i.e., each polarity
change in PM-Request signifies a NRZI code “one’).
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6.2.1.2 When generated
PHY continuously sends PMD the current NRZI code polarity.
6.2.1.3 Effect of receipt
The effect of receipt of this primitive by PMD is not specified.
6.2.2 PMJJNITDATA.indication
This primitive defines the transfer of NRZI data from PMD to PHY.
6.2.2.1 Semantics of the primitive
PM,UNITDATA.indication
(
PM-Indication (NRZI code)
1
The data conveyed by PM-Indication shall be a continuous NRZI code (i.e., each polarity
change in PM-Indication signifies a NRZI code ‘one’).
6.2.2.2 When generated
PMD continuously sends PHY the current NRZI code polarity.
6.2.2.3 Effect of receipt
In normal non-Loopback mode, PM-Indication is continuously sampled by the clock recovery
and Receive Function of PHY.
6.2.3 PM,SIGNAL.indication
This primitive is generated by PMD and asserted to PHY to indicate a change in the status of
the optical signal level being received by PMD.
6.2.3.1 Semantics of the primitive
PM,SIGNAL.indication
(
Signal,Detect(status)
1
The Signal-Detect(status) parameter shall indicate whether the inbound optical signal level is
= on) or below (status = off) the optical signal detection threshold of the
above (status
optical receiver in PMD.
6.2.3.2 When generated
PMD generates this primitive whenever it detects a change in the status of Signal-Detect.
6.2.3.3 Effect of receipt
= off, to enter Quiet-Line-State, and
The effect of receipt of this primitive is, when status
on, to enable detection of other line states.
when status =
10
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6.3 PHY-to-SMT services
The services supplied by the PHY allow the local SMT entity to control the operation of PHY.
The PHY shall perform the requested SMT services preemptively over any requested MAC
Additional detail is provided in SMT concerning conditions that generate these
services.
primitives and SMT actions upon receipt of PHY-generated primitives. The following primitives
are defined:
SM,PH-LINE-STATE.request
SM-PH-STATUS.indication
SM,PH-CONTROL.request
The description of each primitive
All primitives described in this subclause are mandatory.
includes a description of the information that is passed between PHY and SMT.
6.3.1 SM-PH-LINE-STATE.request
This primitive is generated by SMT to request PHY to send a stream of symbols.
6.3.1.1 Semantics of the primitive
SM,PH,Line-Staterequest
(
Line-State-action
1
The line-state-action parameter shall be one of the following:
TRANSMIT-QUIET. When this action is requested, PHY shall send a continuous stream of Quiet
symbols to PM
...
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