4) Module 3: Rapid Delivery Technologies for EA

Lecture 3 introduces the concepts of XML. It describes XML as an Extensible Markup Language for any written language. It introduces the definition of XML elements, attributes, entities and namespaces. It has been a World Wide Web Consortium {W3C} standard from February 1998. While HTML uses standard fixed tags, XML allows any tag to be defined as metadata tags that surround the actual data. Many examples are provided.

Lecture 4 describes the XML Document Type Declaration (DTD) specification for XML elements (which are the metadata tags). 

Lecture 5 defines attribute names, which follow the element name, separated by at least one space and followed by an equal sign, with the attribute data surrounded by single or double quotes.

Lecture 6 continues the definition of XML attributes. It introduces the concepts of Attribute Types where Type ID is a primary key which is typically is a surrogate key. There can only be one ID key. Attribute Type IDREF is a foreign key, of which there maybe be many. Attribute Type ENTITY is used by XML but is analogous to a macro name. It has no relationship to the term ENTITY used in data modeling, which is the logical representation of a physical table in a database.

Lecture 7 discusses the concept of Namespaces, where an element name is unique within an XML document but the same metatags can be used by other documents. XML Namespaces define a Namespace prefix that makes the Namespace:element name universal. Standard DTDs are introduced as well as Repositories, such as XML.org, ebXML.org, BizTalk.org, UDDI.org and ebXML for EDI.

XML Schema Definition (XSD) is introduced that has more extensive data definition rules than DTDs: many more data types; cardinality; data validation etc.

Lecture 8 introduces the concepts of XSL as a programming language for display formatting, written in XML to demonstrate that any language can be defined in XML as a command, where a processor has been written that understands the logic behind that command and executes the appropriate process logic interpretively. This principle is used by an XSL processor for XSL, while a BPEL Processor is used to execute XML-based BPEL code (see Section 6).

An HTML example is used to demonstrate a table in a web page and XSL is then used to form the same table in XSL in a web page. The XSL command <for-each> is used for loop control in XSL, with examples to illustrate.

Lecture 9 uses another HTML example of a book list table, using an XML stylesheet to show how XML can be converted to HTML using a <for-each> loop to dynamically create each row of the HTML table.

Lecture 10 uses another example of a stock portfolio in a table to illustrate sorting on stock price using the <order-by> XSL command. Examples illustrate the use of the Conditional <xsl:if> and <xsl:choose> XSL commands. A final example shows how the earlier table of book titles can be represented as data in XML and (using an XSL Stylesheet) can be converted by XSL for display as an HTML table using the <for-each> XSL command for loop control. This example also illustrates the use of the XSL <choose> command.

Lecture 11 illustrates the default stylesheet used by Internet Explorer 5.0 or higher where the XSL stylesheet command is commented out. The HTML table used in Lecture 10 is then used again with the XSL <choose> command to illustrate additional formatting with loop control.

Lecture 12 discusses the growth of Trading Communities and also Business to Business (B2B) Messaging concepts. It considers the problems of using HTML web pages as messages in a Browser to connect enterprising and contrasts with the use of XML messages to connect those enterprises. The problems discussed in Lecture 1 of different terminology and message formats arise.

XML is not a complete answer: it still needs transformation between those terminology and message format differences. These problems are overcome by industry standards of terminology and message formats in Industry Markup Languages, with XML Transformation (XMLT) products used to make the necessary changes. The other problem of guaranteed XML document delivery across the internet is discussed. The solution is to use common formats for electronic envelopes containing XML messages together with reliable web-based document delivery systems.

Lecture 13 first discusses Commerce One which allows Buyers and Suppliers to transact business with each other using different envelope formats and XML message formats, with Commerce One converting automatically between these different formats.

The problem with Buyers and Suppliers finding each other across the internet is discussed and the principle of a single internet Repository that exists worldwide (like a single Yellow Pages Directory) is discussed.

Messaging and Architecture Standards, such as BizTalk Framework, RosettaNet, ebXML, SOAP, WSDL and UDDI are covered, together with Architecture and Discovery Standards, such as ebXML Architecture are introduced

Lecture 14 discusses the concepts of XML messages sent between Buyers and Suppliers.

Lecture 15 introduces webMethods Integration as the standard for EAI vendors who license the capability from webMethods to deliver XML envelopes and their XML messages reliably across the internet. It discusses the concepts of business integration and rapid business process implementation, with real-time monitoring and analysis. Examples of webMethods Business Integrator for Rapid Business Process Modeling are demonstrated.

Lecture 16 considers the implementation of business process logic and data mapping and discusses the concept of Business Process Monitoring in real-time. It then considers real-time data gathering and automatic transaction logging for historical metrics and trend analysis. 

Lecture 17 covers EAI messaging using Microsoft BizTalk Server that supports complex business process definition, automation and integration with document interchange and business-rules-based routing. BizTalk Server integrates loosely coupled, long-running business processes within and across enterprises. It can handle transactions that can run for weeks and months, not just minutes and hours. BizTalk Orchestration Designer, BizTalk Server Data Mapper, BizTalk Server Concurrent Processes and the BizTalk Project System are all discussed and illustrated. BizTalk uses its own graphical Orchestration Designer rather than using BPMN, but now automatically generates executable BPEL code rather than the previous proprietary XLANG code. It provides central maintenance of Business Rules, which means that business rules can be changed once in one place and automatically change those same business rules wherever they occur.

Lecture 18 discusses the BizTalk envelope message structure, with examples of sample BizTalk documents.

The lecture then introduces EAI messaging using ebXML. ebXML was a worldwide project from November 1999 through May 2001 to enable XML to be used in a consistent manner for the exchange of the electronic business data previously carried out by EDI. The operation of the ebXML Registry Operation at ebXML.org is discussed. The concept of XML message transactions between Buyers and Suppliers is discussed. 

Lecture 20 introduces Web Services Concepts and Protocol Standards, together with transaction recovery implications.

Previously, paper forms were used to communicate between Buyers and Suppliers, with the mail room opening paper envelopes, removing the paper Purchase Orders and Sales Orders and forwarding those documents to the appropriate Purchasing or Sales Departments for processing. That is, people were used as the business integrators. This introduced many document routing errors and data entry errors, with their consequent costs and time delays. Today, XML and Web services are used to reduce these costs and time delays.

This lecture also shows how Web Services can be used to provide a real-time integration solution for the data redundancy problems in many organizations.

Lecture 21 discusses a typical example of an on-line store using Web Services and SOAP messages, to communicate: with a Bank for credit card processing; with Supplier for outsourcing warehouse distribution; and with a Logistics Company for pickup from the Supplier and delivery to the Customer.

The operation of UDDL.org as a single worldwide Repository for Web Services between Buyers and Suppliers is discussed.

Lecture 22 discusses the evolution of the Web Services market through Phase 1 (from 1999-2001), Phase 2 (from 2002-2004) and Phase 3 (from 2005 and beyond). It discusses issues of: Quality of Service; Network Reliability and Security; and real-time messaging. Transaction Recovery and Billing Mechanisms are introduced. A number of Web Services Languages are discussed.

Lecture 23 discusses Web Services Transaction Recovery in detail using the example of the on-line store, the Bank, the Supplier and the Logistics Company discussed earlier in Lecture 21. It considers the problems of Transaction Recovery using both synchronous processing and asynchronous processing. 

Lecture 24 discusses a number of Web Services products and their strategies for Web Services, which include J2EE and .Net. The Microsoft.Net Framework is first discussed extensively: showing that many languages, such as Visual Basic (VB), C++, C# and others are compiled down to a Microsoft Intermediate Language (MSIL). This is then compiled on a Just-in-Time (JIT) basis to machine code depending on the hardware machine code to be executed. This JIT compilation concept is similar to that used for Java.

Lecture 25 discusses IBM J2EE Web Services Toolkit using the IBM WebSphere Application Server. Oracle J2EE Web Services are then discussed, together with Oracle J2EE JDeveloper Web Services Developer.

Lecture 26 discusses Web Services Security Message Protection for Data Integrity, Data Origin Authentication and Data Confidentiality. Data Confidentiality considers encrypting and decrypting data with examples of Symmetric Cryptography and Asymmetric Cryptography.

SOAP 1.0 was inconsistent across vendors. SOAP 1,1 incorporated some interoperability. A number of vendors established the Web Services Interoperability Group (WS-1). Web Services are now interoperable across all WS-I vendors.

The earlier example in Lecture 21 of Business Integration between enterprises now using XML SOAP Messages instead of paper forms is discussed, with Web Services enabling effective real-time integration of legacy databases to be realized. This is a strategy for the introduction of Web Services into an enterprise to achieve real-time integration of legacy databases.

At the end of Section 5 an article on Web Services Product Descriptions is inserted in the Course Handouts. This was downloaded from the internet using a link from Chapter 14 of the Reference Textbook. 

Lecture 27 discusses that Service Oriented Architecture (SOA) uses Web Services for XML messages and XML for executable languages, as discussed in Section 3 on XSL.

The differences between SOA and Event-Driven Architecture (EDA) are first discussed.

Lecture 28 covers Business Process Execution Language (BPEL) comprehensively, with examples of the XML-based commands used by BPEL, together with several examples using BPEL: for Financial Institution Loan Requests; and Airline, Hotel and Rental Car Bookings.

Lecture 29 covers Web Services Choreography Interface (WSCI – pronounced “whiskey”), which supports a message-flow-oriented architecture. It is not a “workflow description language”. WSCI was developed from the start to be Open Architecture as there was initial concern that Microsoft and IBM would make BPEL proprietary. However, BPEL is now also Open Architecture.

Lecture 30 introduces Business Process Modeling Language (BPML) and contrasts it with WCSI and BPEL. BPML was developed before BPEL and WCSI and so is a more comprehensive language as a result. These languages may all evolve over time into a single, powerful XML-based executable language that takes the best parts of each of these separate component languages. Commands by BPML are contrasted to those used by BPEL to show the similarities between both languages. Code examples in BPML are used to illustrate the language further.

Lecture 31 discusses Business Process Specification Schema (BPSS). This is used with ebXML and expresses in XML the commercial terms between Buyers and Suppliers, together with contractual performance response times. If a Supplier accepts a Purchase Order from a Customer, this acceptance is a binding legal agreement for the Supplier to deliver the requested Products or Services to the Customer at an agreed price and time. With this agreement, the Customer has also agreed to pay the Supplier (at the agreed price) following the requested delivery. Messages and interactions sent between these businesses constitute the binding legal agreement between both parties.

BPSS 1.0 was originally contemplated to generate executable code from UML. However, BPSS 2.0 recognized the inconsistency of UML and now considers using BPMN to generate executable BPEL code.

Lecture 32 briefly introduces the concepts of BPMN. A number of SOA products and vendors are then discussed, including: Microsoft; IBM; Software AG; webMethods (purchased in 2005 by Software AG); TIBCO; and Intalio.

Lecture 33 discusses SOA Governance, Enterprise Service Bus (ESB) and the latest developments in Business Process Management (BPM). These consider the differences between BPM 1.0 and BPM 2.0.

An article has been inserted at the end of Section 6 of the Course Handouts on SOA Product Descriptions and Vendor Strategies. This has been downloaded from the Internet using a link from Chapter 14 of the Reference Textbook.

Lecture 34 provides a more complete discussion of BPMN concepts.

Lecture 35 continues the more complete discussion of BPMN concepts, together with an introduction to a live BPMN Tutorial, demonstrating how to develop a Department of Motor Vehicles Driver’s License Examination Process Model diagram in BPMN. This tutorial shows how processes can be developed and changed rapidly, then generated automatically as executable code.

Lecture 37 continues the live BPMN Tutorial, demonstrating how to draw BPMN Flow Lines, Message Lines and Annotation Lines using Visible Analyst. It completes the BPMN Process Model diagram.

Lecture 37 continues the live BPMN Tutorial, demonstrating how to draw BPMN Flow Lines, Message Lines and Annotation Lines using Visible Analyst. It completes the BPMN Process Model diagram for the Department of Motor Vehicles Driver’s License Examination Process.

Lecture 38 continues the live BPMN Tutorial, discussing BPMN Repository Entries and BPMN Reports using Visible Analyst. A Summary of BPMN concludes Module 3.