1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 11783-4:2011Tractors and machinery foragriculture and forestry Serial control andcommunications data networkPart 4: Network layerBS ISO 11783-4:2011 BRITISH STANDARDNation
2、al forewordThis British Standard is the UK implementation of ISO 11783-4:2011.The UK participation in its preparation was entrusted to TechnicalCommittee AGE/6, Agricultural tractors and forestry machinery.A list of organizations represented on this committee can beobtained on request to its secreta
3、ry.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 66346 8ICS 35.240.99; 65.060.01Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was
4、 published under the authority of theStandards Policy and Strategy Committee on 31 December 2011.Amendments issued since publicationDate Text affectedBS ISO 11783-4:2011Reference numberISO 11783-4:2011(E)ISO 2011INTERNATIONAL STANDARD ISO11783-4Second edition2011-12-01Tractors and machinery for agri
5、culture and forestry Serial control and communications data network Part 4: Network layer Tracteurs et matriels agricoles et forestiers Rseaux de commande et de communication de donnes en srie Partie 4: Couche rseau BS ISO 11783-4:2011ISO 11783-4:2011(E) COPYRIGHT PROTECTED DOCUMENT ISO 2011 All rig
6、hts reserved. Unless otherwise specified, 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 either ISO at the address below or ISOs member body in the country of th
7、e requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2011 All rights reservedBS ISO 11783-4:2011ISO 11783-4:2011(E) ISO 2011 All rights reserved iiiContents Page Forewo
8、rd iv Introduction . v 1 Scope 1 2 Normative references 1 3 Terms and definitions . 2 4 Description . 2 4.1 Role of the network interconnection unit (NIU) 2 4.2 Role of the network layer 3 5 Requirements . 6 5.1 Network interconnection unit (NIU) . 6 5.2 Network topology 6 5.3 Network addressing 6 6
9、 Network interconnection unit functions . 7 6.1 Forwarding . 7 6.2 Filtering. 7 6.3 Address translation . 8 6.4 Message repackaging . 8 6.5 Network message 8 6.6 Database management . 10 6.7 Network topology information . 14 6.8 Network interconnection unit parametrics . 16 6.9 Forwarding destinatio
10、n-specific messages by establishing a connection . 22 7 Types of network interconnection units . 29 7.1 Repeater . 29 7.2 Bridge . 29 7.3 Router . 30 7.4 Gateway 30 7.5 Tractor ECU 31 Bibliography 32 BS ISO 11783-4:2011ISO 11783-4:2011(E) iv ISO 2011 All rights reservedForeword ISO (the Internationa
11、l 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 es
12、tablished 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 standardi
13、zation. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for vot
14、ing. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. ISO 11783-4 was prepared by Technical Committee ISO/TC 23, Tractors and machinery for agriculture and forestry, Subcommittee SC 19, Agricultural electronics. This second edition canc
15、els and replaces the first edition (ISO 11783-4:2001), which has been technically revised. ISO 11783 consists of the following parts, under the general title Tractors and machinery for agriculture and forestry Serial control and communications data network: Part 1: General standard for mobile data c
16、ommunication Part 2: Physical layer Part 3: Data link layer Part 4: Network layer Part 5: Network management Part 6: Virtual terminal Part 7: Implement messages application layer Part 8: Power train messages Part 9: Tractor ECU Part 10: Task controller and management information system data intercha
17、nge Part 11: Mobile data element dictionary Part 12: Diagnostics services Part 13: File server Part 14: Sequence control BS ISO 11783-4:2011ISO 11783-4:2011(E) ISO 2011 All rights reserved vIntroduction Parts 1 to 14 of ISO 11783 specify a communications system for agricultural equipment based on IS
18、O 11898-11and ISO 11898-22. SAE J 19393documents, on which parts of ISO 11783 are based, were developed jointly for use in truck and bus applications and for construction and agricultural applications. Joint documents were completed to allow electronic units that meet the truck and bus SAE J 1939 sp
19、ecifications to be used by agricultural and forestry equipment with minimal changes. This part of ISO 11783 is harmonized with SAE J 1939/314. General information on ISO 11783 is to be found in ISO 11783-1. The purpose of ISO 11783 is to provide an open interconnected system for on-board electronic
20、systems. It is intended to enable electronic control units (ECUs) to communicate with each other, providing a standardized system. The International Organization for Standardization (ISO) draws attention to the fact that it is claimed that compliance with this part of ISO 11783 may involve the use o
21、f a patent concerning the controller area network (CAN) protocol referred to throughout the document. ISO takes no position concerning the evidence, validity and scope of this patent. The holder of this patent right has assured ISO that he is willing to negotiate licences under reasonable and non-di
22、scriminatory 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: Robert Bosch GmbH Wernerstrasse 51 Postfach 30 02 20 D-70442 Stuttgart-Feuerbach Germany Attention is dr
23、awn to the possibility that some of the elements of this part of ISO 11783 may be the subject of patent rights other than those identified above. ISO shall not be held responsible for identifying any or all such patent rights. BS ISO 11783-4:2011BS ISO 11783-4:2011INTERNATIONAL STANDARD ISO 11783-4:
24、2011(E) ISO 2011 All rights reserved 1Tractors and machinery for agriculture and forestry Serial control and communications data network Part 4: Network layer 1 Scope ISO 11783 as a whole specifies a serial data network for control and communications on forestry or agricultural tractors and mounted,
25、 semi-mounted, towed or self-propelled implements. Its purpose is to standardize the method and format of transfer of data between sensor, actuators, control elements and information storage and display units, whether mounted on, or part of, the tractor or implement. This part of ISO 11783 describes
26、 the network layer, which defines the requirements and services needed for communication between control functions (CFs) in different segments of the ISO 11783 network. The various types of network interconnection units are defined in this part of ISO 11783. 2 Normative references The following refe
27、renced 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. ISO 11783-1, Tractors and machinery for agriculture and forestry Se
28、rial control and communications data network Part 1: General standard for mobile data communication ISO 11783-2, Tractors and machinery for agriculture and forestry Serial control and communications data network Part 2: Physical layer ISO 11783-3, Tractors and machinery for agriculture and forestry
29、Serial control and communications data network Part 3: Data link layer ISO 11783-5, Tractors and machinery for agriculture and forestry Serial control and communications data network Part 5: Network management ISO 11783-7, Tractors and machinery for agriculture and forestry Serial control and commun
30、ications data network Part 7: Implement messages application layer ISO 11783-9, Tractors and machinery for agriculture and forestry Serial control and communications data network Part 9: Tractor ECU BS ISO 11783-4:2011ISO 11783-4:2011(E) 2 ISO 2011 All rights reserved3 Terms and definitions For the
31、purposes of this document, the terms and definitions given in ISO 11783-1 and the following apply. 3.1 address space allowable range of addresses on a particular subnetwork NOTE When an NIU separates network segments, the same address can be used by CFs on each side of the NIU. 3.2 connection establ
32、ishment of dynamic virtual addresses in an NIU (network interconnection unit) for sending and receiving messages between CFs on different network segments that have different address spaces 3.3 network interconnection unit NIU electronic control unit (ECU) used for interconnecting networks or networ
33、k segments 3.4 port network segment interface to an NIU NOTE An NIU has two or more ports connected to different network segments. 3.5 port pair two ports of an NIU indicating the direction of data flow from one segment to another segment 3.6 transparent CF which provides services to another CF with
34、out it being aware of the source of these services NOTE The CFs need not be aware there is an NIU connecting the CFs together. 3.7 virtual CF apparent CF established by an NIU on one network segment using the same NAME of the actual CF on a different network segment 3.8 actual CF CF established dire
35、ctly by an ECU on the network segment 4 Description 4.1 Role of the network interconnection unit (NIU) 4.1.1 Message transfer 4.1.1.1 General When multiple segments exist in a network, the NIU provides the means of transferring messages from one segment to another. The unit transfers individual mess
36、age frames between two or more ports, of which there is one per segment. BS ISO 11783-4:2011ISO 11783-4:2011(E) ISO 2011 All rights reserved 34.1.1.2 Message-transfer tasks Depending on its type (see 4.2 and Clause 7), the NIU can perform one or more of the following message-transfer tasks: forwardi
37、ng (6.1); filtering (6.2); address translation (6.3); repackaging (6.4). 4.1.1.3 Main performance criteria There are three main performance criteria for determining the suitability of an NIU for a given application: a) maximum number of messages guaranteed to be forwarded per second: if this number
38、is exceeded due to average or peak bus loads, messages can be lost; b) maximum number of messages guaranteed to be filtered per second: if this number is exceeded due to the number of entries in the database, messages can be excessively delayed; c) maximum transit delay: this is used to determine th
39、e worst-case latency for a message transmitted by one CF and received by another CF on another bus segment. 4.1.2 Database management The NIU can also support bridge and database management (6.6), enabling access to, and configuration of, internal databases within the interconnection unit itself. EX
40、AMPLE Although a bridge separates two media segments and the message traffic on each, the network will still be considered a single network in terms of its address space and identifiers, as a result of the communication made possible by the interconnection unit. 4.1.3 Other network layer functions N
41、etwork interconnection units can perform other functions beyond those defined in this part of ISO 11783, as provided by the supplier or as dictated by the network configuration. ISO 11783-1 provides examples of these other functions. 4.2 Role of the network layer The main role of the network layer i
42、s management of the transfer of messages between segments. The network layer includes a number of different types of network interconnection units which, depending on the functions required, can provide these services: the repeater forwards the messages (7.1); the bridge (7.2) filters messages and m
43、anages the message-filter database; the router (7.3) uses address translation to enable a network segment to appear as a single CF to other parts of the network; the gateway (7.4) repackages parameters into different messages for easier transfer, reception and interpretation by CFs; BS ISO 11783-4:2
44、011ISO 11783-4:2011(E) 4 ISO 2011 All rights reserved a special network interconnection unit, the tractor ECU, connects the implement and tractor buses on a tractor or self-propelled implement (see Figure 1, 5.1.3 and ISO 11783-9). As well as these message-transfer functions, the network layer provi
45、des access to, and allows configuration of databases within, the NIU (4.1.2, 6.6 and ISO 11783-1). NOTE The NIU can also participate in the address-claim procedure on behalf of CFs in a subnetwork (ISO 11783-5). However, because the use of a router or gateway for interfacing with a proprietary subne
46、twork is application-dependent, these NIUs are not defined in ISO 11783. Specific implementations can be developed by the component manufacturer, subsystem supplier or the OEM (original equipment manufacturer). Figure 1 illustrates the topology of a typical network in agriculture and forestry that u
47、ses serial control and communications data NIUs. The maximum number of nodes per implement is specified in ISO 11783-2 and the maximum apparent number of CFs on a segment is limited by addressing as specified in ISO 11783-5. BS ISO 11783-4:2011ISO 11783-4:2011(E) ISO 2011 All rights reserved 5P1P2P1
48、P2P1P2 P3tractorenginetransmissionbrakeshitchcontrollernetworkinterconnectionunitnetworkinterconnectionunittractor ECUpower Inputtractor networkimplementnetworkimplementnetworkimplementnetworkimplementnetworkterminatorterminatorterminatorterminatorterminatorimplement busbreakawayconnector implement
49、busbreakaway connectorimplement busbreakaway connectorimplement busbreakaway connectordiagnosticconnectorbus extensionconnectorvirtualterminalmanagementcomputergateway task controllerECUECUECUECUECUECUECUECUECUECUECUlightingcontrollerimplement(rear mountedor towed) ISO 11783or other network ISO 11783or other network implement(front or sidemounted) other standardsnetworkimplement(rear mountedor towed) Figure 1 Typical ISO 11783 network BS ISO 11783-4:20
