CHAPTER 3 EDI standards - UN/EDIFACT
3.1 The need for EDI standards
Just as voice communications requires a common set of rules which everyone
understands and uses to communicate with each other, the use of EDI requires
a common set of standards to be accepted for communication.
The transmission syntax defines the rules for transmitting information
between computers; the data element specifies the meaning, codes and computer
format of the information to be exchanged and the message specifies the
data elements contained in the document to be interchanged. These compare
closely with grammar, vocabulary, abbreviations and sentences that we use
in verbal communication.
3.2 History of EDI standards
In the early days of EDI, electronic messages formats were designed to
meet the needs of individual organizations. The companies connect their
computers together based on proprietary standards. It was not long before
these companies realized the limitations of such proprietary standards.
They saw the need to communicate not only with their trading partners but
with other players within the industry.
Industry standards were then developed to meet the needs of wider communities
of interest. For example, standards, such as ODETTE (Organization for Data
Exchange by Teletransmission in Europe), were developed specifically for
all players in the automobile industry, TradaNet standards catered to the
retail industry in the United Kingdom of Great Britain and Northern Ireland.
Even with industry standards in place, organizations involved in cross-
industry trading still faced a number of barriers, and consequently the
need for national standards became apparent. Two national standards emerged.
They were the ANSI ASC X12 (American Standards Institute Accredited Standards
Committee) in North America and GTDI (Guidelines for Trade Data Interchange)
in Europe.
Although these different national standards generally meet the domestic
needs, they nevertheless were creating difficulties for international transactions.
Trying to resolve this barrier for international communication, several
countries brought this problem to the attention of the United Nations Working
Party on the Facilitation of Trade Procedures (UN/ECE/WP.4), a committee
responsible for streamlining procedures and developing standard documentation.
September 1985 saw the bringing together of the GTDI and ANSI X12 standards.
The UN-JEDI (Joint Electronic Data Interchange) group was formed to develop
an international standard. This co-operation led to the birth of UN/EDIFACT
(or the United Nations/EDI for Administration, Commerce and Trade).
3.3 The UN/EDIFACT standard
3.3.1 The concept of EDIFACT revolves around a single international standard
flexible enough to meet the needs of government and private industry. UN/EDIFACT
is fast gaining recognition and acceptance as the global EDI standard.
EDIFACT defines the syntax rules for the transmission of messages and can
be used across industries, across country boundaries and for both government
and private sectors. EDIFACT is fast gaining popularity in the United States
of America, Europe, Australia, New Zealand and Asia.
EDIFACT covers standardization in five main areas:
(a) The syntax rules;
(b) The data elements;
(c) The segments;
(d) The messages;
(e) The codes.
3.3.2 Syntax rules
The syntax rules are rules governing the structure of an interchange and
its functional groups, messages, segments and data elements. The rules
apply only to data to be interchanged. It is independent of the type of
computers, applications, communications protocols and interchange media
to be used.
The UN/EDIFACT syntax was recognized by the International Organization
for Standarization (ISO) and the Economic Commission for Europe (ECE).
3.3.3 Data elements
Data element is the very basic building block which equates to a word or
a group of words in a sentence. It is the smallest unit of information
within a message. It can be identified by the unique four-digit identification
tag, data element name, data description and representation.
3.3.4 Segment
Segment is the immediate unit of information in a message which equates
to sentences in a passage. A segment consists of a pre-defined set of functionally
related data elements which are defined by their sequential positions within
a set. Each segment is identified by a three-alphabetical segment tag.
3.3.5 Messages
Messages are composed of logically grouped segments required for the type
of message transaction covered. Messages are equivalent to documents. For
example, an invoice in EDI form would be known as the Invoice message. Messages
can be defined by a message specification which is uniquely identified by
the message type and message version number.
3.3.6 Codes
Codes are used as abbreviations. The UN/EDIFACT codes are built upon
the existing ISO codes, such as country codes, location codes, codes for
modes of transport, codes for units of measurements, codes for container
movements, codes for package names and codes for incoterms.
3.4 Benefits of UN/EDIFACT
The benefits of UN/EDIFACT are many:
(a) EDIFACT is a fusion of European and American national standards. Generally,
EDIFACT retains the essence of the two national standards characterized
by its flexibility and efficiency while not compromising its functionality;
(b) EDIFACT is flexible enough to be used across industries and across boundaries
for both government and private sectors in a wide range of EDI applications;
(c) EDIFACT is also supported by a set of rigorous messages design procedures,
thus ensuring that EDIFACT messages which are endorsed by the United Nations
conform fully to the standard and hence are internationally functional.
The essence of a good standard does not lie only in its flexibility, efficiency
and functionality. Its acceptance is of paramount importance. EDIFACT
is fast gaining popularity not only in the United States and Europe, but
also in Australia, China, India, Japan, Malaysia, New Zealand, Republic
of Korea, Singapore, as well as in many developing countries in the Asia
and Pacific region. EDIFACT is the prevailing global EDI standard.
3.5 Organizational structure of UN/EDIFACT
With the birth of UN/EDIFACT, the Economic Commission for Europe (ECE)
was appointed to administer the standard. Two groups of experts under the
ECE Working Party 4 (WP4) emerged. Group of Experts 1 (or more commonly
known as GE.1) oversees data element and automatic data interchange developments;
and Group of Experts 2 (GE.2) deals with procedures and documentation.
For the international development of EDIFACT standards, the GE.1 appoints
individuals called rapporteurs to set up appropriate machinery and facilities
to develop EDIFACT standards in the respective regions. These UN/EDIFACT
rapporteurs are nominated by their respective Governments and appointed
by WP.4. Rapporteurs are appointed to co-ordinate regional activities in
the areas of message development, technical assessment as well as promotion
and documentation.
The first rapporteurs were appointed for North America, Western Europe
and Eastern Europe in 1987. ECE appointed UN/EDIFACT rapporteurs for Australia/New
Zealand and Japan/Singapore in 1991 and the African rapporteur was appointed
in 1993.
Regional EDIFACT Boards (for example, Asia EDIFACT Board, Australia/New
Zealand EDIFACT Board) are appointed locally to support the rapporteurs
in the execution of their responsibilities. Their constitution is not regulated
by WP.4 which allows for regional differences in geography, language and
political environment.
In summary, the organization structure of UN/EDIFACT is as depicted in
the diagram below:
3.6 UN/EDIFACT messages
A message, a structured set of data values relating to a business function,
is a collection of sequenced segments within a defined section. United
Nations Standard Messages, the product of the UN/EDIFACT development process,
are collections of data values conveying general business functions, applicable
to all needs (multisectoral).
UN/EDIFACT classifies messages in three categories:
Status 0
This is a message which is still at draft form, submitted to ECE/WP.4 for
information only.
Status 1
This is message which has been approved by ECE/WP4 for formal trial.
Status 2
This is a recommended draft that has been approved by WP.4 as a formal
recommendation. Messages in this category are known as United Nations Standard
Messages (or in short UNSMs).
Within each document status 0-2, there may be many revisions.
3.7 UN/EDIFACT publications
3.7.1 International publications
The set of UN/EDIFACT documentation is published and maintained by ECE/WP.4
and the International Organization for Standardization (ISO).
This documentation forms a set of internationally agreed standards, directories
and guidelines for the electronic interchange of structured data, and in
particular, data relating to trade in goods and services, between computerized
information systems.
Within the context of UN/EDIFACT, the major relevant documents are :
(a) Guidelines & Rules;
(b) ISO 9735 Syntax Rules;
(c) The UN/EDIFACT Syntax Implementation Guidelines;
(d) The UN/EDIFACT Message Design Guidelines;
(e) UNTDID (The United Nations Trade Data Interchange Directory)
for status 2 messages which includes:
(i) EDMD - the EDIFACT message directory
(ii) EDSD - the EDIFACT segments directory
(iii) EDCD - the EDIFACT composite data element directory
(iv) EDED - the EDIFACT data element directory
(v) EDCL - the EDIFACT code list directory
(f) UN/EDIFACT Working Directory Set (for status 1 messages).
UN/EDIFACT directories are published twice a year by the United Nations
and are distributed through the regional EDIFACT Boards and local EDIFACT
Committees. Any parties interested in obtaining copies of the documents
are advised to contact their local EDIFACT Committee or the regional EDIFACT
Board.
3.7.2 Country-level publications
UN/EDIFACT participating countries also publish country directories based
on the particular country's need such as the language and level of technical
development.
For example, in China, a Chinese version of the directory sets was developed
to cater to the needs of the local message designers. In the Republic of
Korea, a Korean version of the directory was developed. In Singapore, the
SGD (Singapore EDIFACT Directories) was developed, in which new or amended
segments, data elements and codes for local EDI systems form part of the
directory sets.
3.8 The Asia EDIFACT Board
3.8.1 Mission of the Board
The Asia EDIFACT Board, or ASEB in short, was formed with the mission to
guide, stimulate and promote the development and use of the UN/EDIFACT standards
in its member countries or economies.
ASEB is the representative body taking care of all EDIFACT matters in this
region.
3.8.2 Members of ASEB
Over the last five years, the Board has been greatly expanded. It now
has ten participating countries :
Country
Member since
Represented by
1
Japan
August 1990
Japan EDIFACT Committee
2
Singapore
August 1990
Singapore EDI Committee
3
Republic of Korea
April 1991
Korea EDIFACT Committee
4
Taiwan
province of China
September 1991
Taipei EDIFACT Committee
5
China
September 1991
China EDIFACT Committee
6
Malaysia
May 1992
Malaysia EDIFACT Committee
7
India
August 1992
India Ministry of Commerce
8
Thailand
February 1994
Thailand EDI Council
9
Philippines
November 1994
Philippines EDIFACT Committee
10
Sri Lanka
November 1994
Sri Lanka Export Devlopment Board
In addition, Hong Kong has been participating in ASEB meetings and activities
since 1990 as "observer" economy.
The contact point for each member/observer country/economy of ASEB is attached
as Annex I of this document.
3.8.3 ASEB organization structure
The ASEB organization structure is as follows:
3.8.4 ASEB Joint Working Groups
Joint working groups are established under ASEB to promote the sharing
of information and expertise among member countries and to represent the
joint interests of the Asian countries at United Nations meetings.
A total of nine joint working groups have been established under ASEB :
(1) Education and awareness joint working group (AS AEG)
The AS AEG was set up to promote and encourage the use of EDI and EDIFACT
in Asia by assisting ASEB to organize and develop relevant educational and
promotional programmes.
(2) Technical assessment joint working group (AS TAG)
The AS TAG was set up as the technical consulting group to support ASEB
on the technical aspects of EDIFACT messages development and to assess messages
developed by the various working groups for structure and syntax conformance.
(3) Security joint working group (AS SWG)
The mission of the AS SWG is to serve as a task force for the development
and promotion of UN/EDIFACT security within and among member countries/economies.
(4) Financial joint working group (AS FWG)
The mission of the AS FWG is to stimulate the joint application of EDI
and EDIFACT among the banks in the member countries.
(5) Sea Transport joint working group (AS TWG - sea)
The mission of the AS TWG (sea) is to stimulate the joint application of
EDI and EDIFACT in the maritime transport sectors of the member countries.
(6) Air Transport joint working group (AS TWG - air)
The mission of the AS TWG (air) is to stimulate the joint application of
EDI and EDIFACT in the air transport sectors of the member countries.
(7) Customs joint working group (AS CWG)
The AS CWG focuses on the electronic communication requirements between
the trading community and the customs/trade departments in the various member
countries.
(8) Purchasing joint working (Retail/Distribution) (AS PWG)
The AS PWG (Retail/distribution) looks into developing and promoting the
use of UN/EDIFACT messages for the retail/distribution sector.
(9) Purchasing joint working (Electronics & Computer Group) (AS ECG)
The AS ECG is set up to develop and maintain a set of standard messages
to facilitate EDI in the electronics manufacturing sector.
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