moda-ml, an interoperability framework for the textile ...

MODA-ML, AN INTEROPERABILITY FRAMEWORK FOR THE TEXTILE-CLOTHING SECTOR Nicola Gessa, Fabio Vitali Dept. of Computer Science - University of Bologna

Guido Cucchiara SOI, Gruppo Progema, Torino, Italy

Piero De Sabbata, Massimiliano Fraulini, Massimo Marzocchi ENEA, Bologna, Italy

Thomas Imolesi FTI – Forum Tecnologia dell’Informazione – Laboratorio XML, Bologna, Italy

Luca Mainetti Dept. of Electronics and Information – Politecnico di Milano, Italy

ABSTRACT The MODA-ML project aims to enhance the interoperability between enterprises in the Textile/Clothing sector defining a common interchange language based on a set of XML business components and on a framework to exchange business documents related to production processes. The message switching system is built on a peer-to-peer architecture and is based for the transport specification on the ebXML standards. In order to enforce this architecture a set of tools has been developed to face the security and the maintenance of the system, and to encourage the diffusion of MODA-ML framework. Some considerations on the first phase of the experimentation conducted by a group of leading Italian T/C enterprises are presented at the end of the paper. KEYWORDS Interoperability, XML, ebXML, e-business, MODA-M L

1. INTRODUCTION The business processes are constantly moving toward integration with the modern informatic systems and in the new related communication mechanisms. While internal business processes are already wide supported by the tools provided by the information technology, processes that require contributes from different enterprises are still greatly entrusted to human personnel. In a scenario of global competition a more efficient interoperability among the various actors involved in a specific production process can be fundamental for the survival of the enterprises especially when the production processes are strongly conditioned from every particular contribute coming from each firm. This is the case of the Textile/Clothing sector: it is made of a heterogeneous set of small-medium enterprises, all co-operating to the overall result, each of them takes care of a single aspect of the production process. Usually this co-operation is rules with the exchange of specific documents.

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International Conference WWW/Internet 2003

In [12] is outlined the semantic aspect of the interoperability problem: to make an interoperability solution really useful a common exchange language must be defined on which the business message can be expressed in: this paper pointed out XML as the basic solution for structuring the information to be exchanged. The MODA-ML project (Middleware tOols and Documents to enhAnce the Textile/Clothing supply chain through xML) was born to build an architecture to provide an interoperability framework among the enterprises in the T/C sector and aims at contributing to establish an European standard for the sector. This project stems from the collaboration between a number of research organisations, among which Politecnico di Milano, ENEA, Domina, Gruppo SOI, Institut Francais Textil Habilliment (IFTH) and a group of leading Italian Textile/Clothing manufacturers. It is supported by the Fifth Framework programme of the European Commission within the IST (Information Society Technology) initiative (more information can be found in http://www.moda-ml.org). The MODA-ML project ended in April 2003. The main aim of the project was reached within the allotted timeframe: an architecture and a set of co-operating software modules that allow different enterprises to exchange messages related to their production process. In section 3 of this paper, we outline the basic structures of the proposed fra mework. Starting from the EDI experience, MODA-ML project is based on the definition of a vocabulary of XML business components and of a set of public, modular document types built out of those components, and on a message switching architecture for the documents delivery. Activities in the project, as described in section 4, are continuing even after its official end: we are currently working on aspects of dictionary maintenance, security and a partner simulator for testing purposes. Besides the implementations, a constant collaboration has been set up with important firms of the Textile/Clothing sector; they have been involved in various phases of the project development, from the requirements collection to the testing of the implemented software. This experimentation is still in course and it is being retargeted to a larger set of enterprises. A few experiences will be summarised in section 5. Section 6 contains some conclusions and pointers for future activities.

2. A VIEW ON SOME INTEROPERABILITY ASPECTS At the start of the MODA_ML project in 2000, there was very limited experience of automating B2B processes. Most of the innovation was aimed at automating internal business processes. In many cases, even this was usually only within individual departments, leaving inter-organisational processes to manual or at best semi-automatic management systems. The only existing interoperability solutions were based on EDIFACT technology, and EDITEX, a subset tailored for the Textile/Clothing supply chain. The inflexibility of these standards means that implemented solutions could not be easily adapted to the specific needs of organisations. Whatever the adopted approach, the aspects to consider in order to design a new architecture must include: • The requirements expressed by the enterprises, which the solutions refer to. • The enterprise informatization levels and the technologies adopted for the internal data management. • The number of reference standards to be considered, both finalised and in development. • Any possible interaction with other solutions as proposed by others. The methods used to face and solve each of these points could determine the success or the failure of the proposed solution. In the following we discuss more thoroughly such considerations. Any new interoperability architecture must by definition, work with existing internal enterprise information systems. Usually for economic and practical reasons, there is little willingness to change these because of the implications this has to redefine all the stages of the production process. Moreover a successful solution requires consensus from the whole community, which requires that it must work within the restraints of the ICT, economic and human resources available to all of these enterprises. Any widely used specification defined from relevant standardisation bodies must be considered during the design phase. Such specifications cover both the communication protocols on the Internet, the mean of exchange used for message exchanges among firms (for example SOAP on ebXML) and the languages available for creating documents and messages (for example XML). It is excessive to propose a completely new protocol interchange or to introduce a new standard.

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Being open-source and free is a good starting point to encourage the adoption of a solution, especially when targeting the SME and their technology providers that usually have not any resources available; flexibility is another aspect to consider in order to win support from ERP systems, legacy systems and SME. The MODA-ML project tries to address these issues. Differently from centralised architectures such as those found in ASPs (Application Service Providers) that provide services from a central system, the MODAML architecture deals with a peer to peer architecture; in this way each firm can communicate directly with its correspondents in the supply chain using simple software modules and a transport interface, without passing from any other intermediary. The only central point of reference is a repository that is used to maintain the document templates that can be adopted during the interchange processes.

3. THE MAIN OUTCOMES OF THE MODA-ML PROJECT The project guidelines are: • XML technologies for defining semantic infrastructure of message based data exchange; • ebXML and SOAP to allow document interchange in an e-business scenario. • Very low technological entry threshold to install and run the tools needed in the framework. The first output of the MODA-ML project was the creation of a vocabulary of XML business components and a modular set of public document types to support the information exchange in the supply chain: XML is used to create a sector-specific language, based upon the know-how of EDITEX [2] experience. The resulting documents inherit many XML characteristics: they are human readable, easily customisable, adaptable and expandable. Human readability is important when these kinds of documents are not automatically generated but are edited or checked by human personnel; since this is a common case in small firms, this aspect facilitates spreading of electronic data management in the business process. The second output was the design of a middleware architecture based on ebXML messaging service specifications and SOAP protocol for a message switching system; this architecture relies on simple software module to send, receive, validate and manage the messages. An ordinary mail service and a plain data base management systems (such as MS Access) are the only fundamental software tools needed for exchanging MODA-ML messages. In figure 1 is showed the structure of the MODA-ML architecture. Validation Schema

Company information system

XML

FAX

MSH

Digital certificate Collaboration protocol Agreement

Company A

MSH

E-Mail client

Validation Schema

XML

Check digital certificate

Printer

Browser

Company Information System

Company B

Figure 1. The proposed architecture from MODA-ML project

3.1 The MODA-ML Document Factory The first step in the development of MODA-ML project was to write a dictionary of XML business components and to define a set of document types built upon those components. XML components and document definition arise from the know-how produced from EDIFACT/EDITEXT technology and exploiting the innovative XML characteristics like human readability, flexibility and content structuring. The documents are meant to be exchanged in the communications of enterprises within the T/C supply chain. The set of MODA-ML messages is composed of fourteen documents concerning the Textile SupplierClothing Manufacturer ring. Some of these documents are listed in Table 1. Some components of these

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documents are specialised for particular needs, but many components are shared by all the documents. Each component of the dictionary represents in fact a well-defined concept that can be specified in the messages. This organization of the dictionary makes it possible to perform the necessary distinction between the syntactical model, the semantic model and the transport model of the messages being exchanged. Table 1. Some of the MODA-ML document types Document name Catalogue Textile product data Articles pre-selection Fabric order Order response Order change Order status report

Description The list of products offered for sale The technical characteristics and properties of the fabric article The anticipation of articles included in the Clothing Manufacturer's collection The order placed by the Clothing Manufacturer The response provided by the Fabric Supplier The order change initiated by the Clothing Manufacturer The status of the fabric order reported by the Supplier

Direction Textile→Clothing Textile→Clothing Textile←Clothing Textile←Clothing Textile→Clothing Textile←Clothing Textile→Clothing

The components, thus, represent a set of common “semantic blocks” that, once defined, can be used in different circumstances with always the same meaning. The creation process of a new document type includes: • The selection of a set of semantic blocks that define the concepts the document type must represent • The assembly of these blocks and the definition of rules and constraints to express the interrelations existing among the concepts they represent. Using this approach it becomes fundamental to correctly identify the semantic blocks related to the role of the document in the process, whereby the document specifications are then consequently defined. The effective implementation of the vocabulary is done using a database application that provides a sophisticated description of the defined basic components. This database collects any information on the semantic blocks needed to build the document types. Such information include the name of the XML element, its description and the associated proprieties such as data format, length, range of permitted values and so on. The vocabulary further specifies a root element for every document type and all the relations existing among the elements such as sequence, cardinality and so on. A simple application will then re-create the complete set of rules (an XML Schema) for each document type by starting from the root element and following the defined relations. MODA-ML also provides a set of XSLT stylesheets to create HTML pages off the XML instances so that the document content can be visualised in a readable manner even if using a simple Web browser. The Vocabulary represents the core of the management of every aspect related to the MODA-ML document types, schemas and instances. We call this approach the XML document factory.

3.2 A message switching system for business documents exchange Once the structure of the vocabulary is defined, the next steps consists in the implementation of a communication system to exchange MODA -ML documents between the enterprises of the Textile/Clothing sector and a set of tools to help the enterprise integrate the MODA-ML exchange mechanism to their internal processes. These tools are collectively called the message switching system. The message switching system defines a transport protocol based on ebXML messaging service specifications; ebXML (Electronic Business using XML) [7] is a set of specifications from UN/CEFACT and OASIS that defines a collaboration framework over the Internet to enhance interoperability between enterprises. The main aim of ebXML is to support two different aspects of the interoperability processes: • The semantic definition of the documents: ebXML proposes a set of “core components” used to define the semantic value of a document. Differently from the EDI framework, ebXML emphasises the importance of these components on the entire document structure, and this aspect gives ebXML more flexibility with respect to EDI.

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Several technical specifications on the communication protocol: MODA-ML follows ebXML transport specifications Since the Textile/Clothing sector is composed of various kinds of enterprises, each characterised by a different level of technological sophistication in their information systems, it becomes fundamental to create simple software modules that can be made publicly available, providing an easy and low-cost integration with complex legacy information systems within skilled companies. The main component of the MODA-ML message switching system is the Message Service Handler (MSH), that acts as an email client for the transport of the MODA-ML documents: it takes care to validate MODA-ML documents and to send and receive them over the Internet using SMTP as its transport protocol. In figure 2 is showed the MSH interface that appears like a common email client.

Type Date

Sender

Status: Valid,,Signed, …

Status: Sent,Ack received… Figure 2. The Message Service Handler interface

4. ADDITIONAL ACTIVITIES IN THE MODA-ML PROJECT Besides basic aspects of document structuring and message exchanging, recent activities in the MODA-ML project were performed in a number of areas including: • Security aspects for authentication and non-repudiation of MODA-ML messages • Integration of user guides and XML Schema as automatically generated products of the MODA-ML vocabulary • A virtual enterprise simulator for testing new MODA-ML implementations

4.1 Security module Business transactions need to be confidential and require a certain level of security. Given the economic relevance of these transactions, it is necessary to provide enterprises with techniques to protect them against ICT related threats. However, guaranteeing legal aspects of the transactions is fundamental to develop a service that can gain the confidence of the community. The security module must provide a set of functionalities to guarantee: • Confidentiality: any unauthorized access to the message content must be prevented. • Integrity: the receiver should always be able to verify the message integrity and point out alterations in the data. • Authentication: the receiver must be guaranteed of the identity of the message sender.

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Non-repudiation: the receivers must be guaranteed that the senders will never be able to successfully disown any message they sent. Such requirements can be achieved using cryptography and digital signature, for instance based on asymmetric -key algorithms and digital certificates emitted by a trusted Certification Authority. The basic MODA-ML message switching board does not provide the necessary security guarantees: for this purpose a software module has been developed that implements some security aspects and that can be easily and efficiently integrated within the main modules of MSH. The mechanism adopted to guarantee confidentiality, integrity, authentication and non-repudiation of a conforming MODA-ML message are based on XML–Signature [6] and XML– Encryption [6], two W3C standards that allow respectively to sign an XML document with a digital signature and to encrypt an XML document or fragment with an electronic key: both standards are fully compliant with the ebXML digital signature and greatly simplify interoperability with other frameworks that adopt ebXML specifications. The current 1.1.8 version of the MODA-ML security library implements the XML Signature protocol, while XML Encryption will be available in future versions. The MODA-ML security library is a dynamic library (dll) based on the standard cryptographical algorithms of the MS-Windows library. This library allows documents to be signed with a X509 digital certificate. The contents of the document are thus guaranteed to have been sent from the owner of the certificate and to have been received without modification. The adoption of MS-Windows library allows the free module of MODA-ML to support encryption and digital signature without cost on any Windows XP/2000 workstation. The security module integration was released to external MODA-ML users in May 2003. MODA–ML specifications also comprise capabilities of requiring acknowledgement messages in order to inform the sender that his/her message has been received and to implement the non-repudiation aspects of the communication mechanism. The Message Service Handler uses five security levels, each corresponding to a different combination of exclusive or combined use of cryptography, signature and non-repudiation: 1. Forwarding messages with digital signature. 2. Forwarding encrypted messages. 3. Forwarding encrypted and signed messages. 4. Forwarding messages and acknowledgements with digital signature. 5. Forwarding encrypted and signed messages and acknowledgements. In order to achieve a complete interoperability among all the subjects, the security features of the MSH can be used even by applications that do not directly implement security features.

4.2 Dictionary maintenance E-business processes are prone to continuous changes because of new collaboration relationships, new legal dispositions, new standards adopted in specific production sectors. Document type definitions change consequently, and it becomes necessary to rearrange the structure of the messages in order to follow the new situation. Certainly this could not be a simple task, especially considered the different requirements rising from every situation. Also a minimum change in particular specification can require much time in new verifications of the correctness of the new necessary schemas and to test their integrity. But we can minimise these costs using a set of tools for the automatic maintenance of some aspects of the documents. Since all the documents used in the MODA-ML message switching system are composed starting from a set of defined elements registered in a database, we could think to manage the operations associated with the changing of a process specifications starting from the implicit definition held in the DB. But this is not enough: we know than not only computer systems have to be updated, but also human personnel should be clearly informed and instructed about the new specifications adopted and about the new usage of the documents. And also this could produce the rewriting of hundreds of documentation pages. These two really practical aspects in the manage of a system have been faced implementing a web service that provides a set of tools to automatically generate the document schemas and complete user guides starting from the implicit definitions included in the DB. These tools are: • An automatic generator of XML Schemas for every MODA–ML document that could be exchanged. • An automatic generator of User Guides that explains in details every aspect related to the usage of MODA–ML documents.

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An on-line dictionary to allow accurate researches on elements, contents and definitions contained in the dictionary. MODA-ML staff and the pilot users can generate the XML schema and the user guide on every message also in course of definition; generating XML schemas or user guides produces documents that can be immediately downloaded. A generic user that wants information about the messages usage can only download all the developed versions of the schemas and the users guides. These operations are all ASP applications executable from web (www.moda-ml.net/moda-ml/repository/guide).

4.3 A virtual partner simulator for testing purpose One of the main hindrances in proposing a new solution is represented by the different attitudes in using and adopting them by the enterprises. “Why should I change my production processes?”, “Which are the real advantages that I can take introducing such new method in my firm?”; these are some of typical questions to whom we must respond to convince of the benefits of a new technological solution. In order to face practically these kinds of questions, MODA-VIP (MODA-ML compliant Virtual Interoperability Partner) application has been developed (in the framework of the TEXSPIN project) to implements a virtual enterprise simulator. The target of MODA-VIP is to allow a potential user of the framework proposed by the MODA-ML project to approach it. The basic functions of the simulator are available for everyone, without the requirement of any experience with the XML language. So it is possible, for anyone who never used documents for the e-business, to begin knowing its advantages and functionality following a guided path through them. For more complex functions of the simulator, a basic knowledge of the MODA-ML project and XML language is required. The simulator consists in two main components: • A web site containing all the information needed to use it, as how-to and a guided-tour. • A web service, which is the simulator engine. Its task is to receive and produce exchange messages.

5. THE EXPERIMENTATION PHASE During the project the pilot users have begun to experience the project results; the first phase involved them in the documents validation and in analysis of their capabilities to fit information flows that were already managed via phone or fax. After the positive conclusion of the validation they have begun to insert the XML documents in the real workflow with their customers and suppliers. For the experimentation purpose each pilot user experienced a different approach to integrate the flow of XML documents in their company information systems: ad hoc development of the information systems, Oracle modules to manage XML, generalised XML to DBMS mapper, etc. It must be taken into account that each company information system is the result of many person-years of development and customisation to the specific industrial organisation and decisional hierarchy. The introduction of the MODA-ML framework has suggested further evolution of the internal information systems, with the aim to offer automatic support to the workflow and adding new services to the customers (previously not supported as order advancement status communication, map defects auto-certification). The second important result has been that, for the industries, the adoption of the data exchange framework has been very inexpensive for the industry. For example, in a company that had already an ERP system (supporting the decisional flow of purchase order receiving and order response sending), the additional cost to connect each new type of XML document (purchase order, order response, despatch advise, etc) has been estimated in about half person-day after the first one. In general sending new documents towards the partners has resulted much more simple than receiving documents. Meanwhile companies that were not able to completely support the flow of the documents, are considering the opportunity to enhance their systems while the XML documents can be exchanged between the offices via e-mail (being them already in digital format and being accessible via any Web browser). This means that the results of the project have been able to open new opportunities for the technology suppliers, offering solutions for resources and suppliers management being perceived as ‘another competitor’ for them.

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Furthermore the project results have been able to attract other firms than the pilot users and some experience has begun between pilot users and other partners, while a consortium of about 70 firms of the textile district of Biella has chosen to adopt the frameworks for their exchanges. The main benefits for the companies are the availability of simple entry point tools and the fact that their partners (customers or suppliers) can participate with very poor investments; for example a pilot users sends every night ‘order advancement status’ XML documents to over 150 customers only exploiting the email services; this means that they are able to view the status as a ‘fax’ without any investment, but, if they will invest, they will be able to assume the XML documents as an input for their planning tools. But the most important result obtained by the MODA-ML project is the role inside the CEN/ISSS TEXSPIN workshop. This workshop, promoted by Euratex and supported by CEN/ISSS (the department devoted to ICT standards within the European Commitee for Standardisation, CEN), aims "to provide the Textile/Clothing sector with an open pre-normative platform for electronic data interchange based on XML documents" and represents a starting point for the future developments of standards for this sector.

6. CONCLUSIONS The MODA-ML experience has not only been studied for future applications, but begins to find practical applications in some subsectors of the Textile/Clothing supply chain: MODA-ML has been developed involving enterprises of the T/C sector in order to have a reasonable feedback from practical situations. The involvement of Italian and European industry trading associations (Sistema Moda Italia, Associazione Tessile Italiana and Euratex) is a confirmation of the interest that the approach of Moda-ML has aroused. Using XML technologies not only has made possible to involve small and medium enterprises with different technological levels, and to integrate MODA-ML with more sophisticated information systems, but it also has shown and suggested to the firms that XML can be used to efficiently restructure their internal business processes. Finally, from a technological point of view, the project has demonstrated the feasibility of the construction of an open community of firms that can co-operate without a proprietary approach and has demonstrated a path to the diffusion of standardised approaches for both large and very small enterprises on the same technological framework.

REFERENCES [1] EDIFACT: http://www.unece.org/cefact/ [2] EDITEX: http://www.editexfrance.org/index_fr.htm [3] XML: http://www.w3.org/XML [4] XML Schema: http://www.w3.org/XML/Schema [5] XML: http://www.w3.org/Encryption [6] XML: http://www.w3.org/Signature [7] ebXML: http://www.ebxml.org/ [8] SOAP: http://www.w3.org/2002/ws [9] P. Censoni, P. De Sabbata, G. Cucchiara, F. Vitali, L. Mainetti, T. Imolesi, MODA-ML, a vertical framework for the Textile-Clothing sector based on XML an SOAP, Challenges and Achievements in Ebusiness and E-work, B. Stanford-Smith et al. (Eds.), IOS Press, 2002 [10] TEXSPIN: http://www.atc.gr/texspin [11] CEN/ISSS: http://www.cenorm.be/isss [12] W. Hasselbring, Hans Weigand, Languages for electronic business communication: state of art, http://infolab.kub.nl/pub/itrs/itrs009.pdf

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