IEC PAS 62412:2005

PUBLICLY
IEC
AVAILABLE
PAS 62412
SPECIFICATION
First edition
2005-08
Real-time Ethernet P-NET
on IP specification
Reference number
IEC/PAS 62412:2005(E)
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PUBLICLY
IEC
AVAILABLE
PAS 62412
SPECIFICATION
First edition
2005-08
Real-time Ethernet P-NET
on IP specification
 IEC 2005  Copyright - all rights reserved
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– 2 – PAS 62412 © IEC:2005 (E)

CONTENTS
FOREWORD.3

INTRODUCTION.4

1 Scope and object.5

2 Normative references .5

3 Conventions .5

4 61158-2 Physical Layer specification .6

4.1 OSI Data Link Layer .6
4.1.1 MAC sublayer .6
4.1.2 LLC sublayer .6
4.2 OSI Network layer .6
4.3 OSI Transport layer .6
5 61158-4 Data Link Layer protocol specification.7
5.1 Terms and definitions .7
5.1.1 P-NET-route .7
5.2 Additions to terms and definitions .7
5.2.1 IPNetTable .7
5.2.2 IPNetID.7
5.2.3 UDP port number .7
5.2.4 Nettype.7
5.2.5 IP Range net.7
5.2.6 UDP Range net.7
5.3 Type 4: Additional symbols and abbreviations .8
5.3.1 Constants, variables, counters and queues.8
5.4 Type 4: Data Link Protocol Definition .8
5.4.2 PhIDU structure and encoding.9
5.4.3 Frame check sequence .10
5.5 Additions to Frame check sequence .11
5.5.2 Common DLPDU structure, encoding and elements of procedure .11
5.6 Additions to P-NET-route field.11
5.7 DLPDU-specific structure, encoding and elements of procedure .13
5.7.2 Request P-NET-route generation.17

5.7.3 DL-route generation .18
6 61158-5 Application Layer service definition.20
7 Addressing conventions for P-NET on IP.25
8 Translation of P-NET address to IP address .27
9 Dynamic clients .28
10 Broadcast / Netcast .28
11 Package format .28

PAS 62412 © IEC:2005 (E) – 3 –

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
Real-time Ethernet P-NET on IP specification

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote

international co-operation on all questions concerning standardization in the electrical and electronic fields. To

this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,

Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
A PAS is a technical specification not fulfilling the requirements for a standard but made
available to the public.
IEC-PAS 62412 has been processed by subcommittee 65C: Digital communications, of IEC
technical committee 65: Industrial-process measurement and control.

The text of this PAS is based on the This PAS was approved for
following document: publication by the P-members of the
committee concerned as indicated in
the following document
Draft PAS Report on voting
65C/360/NP 65C/376/RVN
Following publication of this PAS, the technical committee or subcommittee concerned will
transform it into an International Standard.
It is intended that the content of this PAS will be incorporated in the future new edition of the
various parts of IEC 61158 series according to the structure of this series.
This PAS shall remain valid for an initial maximum period of three years starting from
2005-08. The validity may be extended for a single three-year period, following which it shall
be revised to become another type of normative document or shall be withdrawn.

– 4 – PAS 62412 © IEC:2005 (E)

INTRODUCTION
The P-NET on IP specification is designed for use in an IP-environment. P-NET on IP enables
use of P-NET (IEC 61158, type 4) real-time communication wrapped into UDP/IP packages.

P-NET packages can be routed through IP-networks in exactly the same way as they can be

routed through non-IP-networks. Routing can be through any type of P-NET network and in

any order.
Nodes on an IP-network are addressed with two P-NET Route elements, but this is entirely

handled by the IP-nodes. This means that any P-NET client (master) can access servers on
an IP-network without knowing anything about IP-addresses.

PAS 62412 © IEC:2005 (E) – 5 –

Real-time Ethernet P-NET on IP specification

1 Scope and object
This PAS consists of paragraphs that are meant to be additional to the definitions and

specifications, which are already found in the IEC 61158 series. Following each heading,

there will be a reference to which paragraph must be inserted or replaced within the relevant

IEC 61158 series.
After the modifications to IEC 61158 series a few descriptions explain how to perform address

conversions and handle dynamic clients.

NOTE These descriptions are more implementation specific and will not be included in the normative parts of the
new standard.
2 Normative references
The following referenced documents are indispensable for the application 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.

IEC 61158-2:2003, Digital data communications for measurement and control – Fieldbus for
use in industrial control systems – Part 2: Physical layer specification and service definition

IEC 61158-4:2003, Digital data communications for measurement and control – Fieldbus for
use in industrial control systems – Part 4: Data link protocol specification

ISO/IEC 8802-3, Information technology – Telecommunications and information exchange
between systems - Local and metropolitan area networks – Specific requirements – Part 3:
Carrier sense multiple access with collision detection (CSMA/CD) access method and
physical layer specifications
RFC 768 (UDP, User Datagram Protocol)

RFC 791 (IP, Internet Protocol)

3 Conventions
This PAS specifies paragraphs that shall either be replaced or added to the IEC 61158 series.
Paragraphs that shall be replaced are indicated with the paragraph number(s) in question as

reference and begin and end with the lines as shown:
----------------------------------- Replace begin --------------------------------
modified text
----------------------------------- Replace end --------------------------------
Paragraphs that shall be added are indicated with first paragraph number(s) to add a
...