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ERP & Web Services - 2013S-. Clinton E. White, Jr Professor of Accounting & MIS College of B&E University of Delaware. ERP (a.k.a ES). ERP (Enterprise Resource Planning) What is the ultimate goal of an ERP? To model the entire business enterprise in software
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ERP & Web Services - 2013S- Clinton E. White, Jr Professor of Accounting & MIS College of B&E University of Delaware
ERP (a.k.a ES) • ERP (Enterprise Resource Planning) • What is the ultimate goal of an ERP? • To model the entire business enterprise in software • To process, integrate and make available every bit of information necessary to run the business • Why is it so difficult to accomplish? • Requires a long term commitment to remodeling your business in software • Changes will be significant • Resources will be stretched • Employees will be stressed • Risks are significant
ERP vs. Web Services • ERP • Is a tightly integrated system • Requires “deep linking” • Web Services • Are loosely coupled systems • Does not require deep linking
Web Services • What are Web services?
Today’s Quiz • What was the problem that XML originally sought to address?
Major Premises of WS • Web services are robust because they are simple and flexible (wrap-arounds): • Do not require “deep” linking • Loose coupling = Flexibility in complex environments • Based on a bottom-up, organic approach to IT that respects context • Based on second generation Web IT designed to automate connections
Solve the N-squared Problem • How would you explain the N-squared problem?
Connecting Software Apps • So how do you connect software applications over a network? • Old mental model: Mechanistic • New mental model: Flexiblity
The EDI Solution • We have been connecting business applications for years with EDI: • What’s the problem with EDI?
Business Value • What is the “different way” that Web services generate business value from IT?
Web Services • What are the basic principles?
Web Services Architecture • Foundation Standards & Protocols: • Standards: XML … WSDL … UDDI • Protocols: TCP/IP … HTTP … SOAP • The Service Grid: • A set of specialized utilities: reduces the complexity that participants must support & provides an opportunity for accelerated learning & improvements: • Shared utilities: • Security … 3rd party audit & assessment … Billing & pmt • Service management … managing resources • Resource knowledge management … finding & communicating • Transport management … routing & delivery
Web Services at Work WSDL wrapper WSDL wrapper Vendor Managed Hubs W S I Vendor Managed Hubs Amazon DBMS Other E-businesses XML data in a SOAP envelope W S I • WSDL – Web Services Description Language: • Describes how to interact with the Web service processes • Data types … Port types … Operations … Messages • SOAP – Simple Object Access Protocol: • A protocol for messaging & communication between software applications • Envelope … Body (XML message & data) • UDDI – Universal Description, Discovery & Integration • A directory of available Web services & details about how to access them … how to use the interface
Fed Ex My Business’ Shipping Software • XML • SOAP FedEx Compatible Solutions • Offer FedEx Services within your own software apps • FedEx provides the interface to process your data & provide other services
PayPal.com My Small E-Business • XML • SOAP PayPal.com • Process an order • Customer gets ready to check out • Processes the payment by CC or account • Returns a completed payment record • Keeps all payment info in my account • Process the completed payment, record the sale, & ship the item
SOAP • What is SOAP?
SOAP • <?xml version="1.0"?>< soap:Envelopexmlns:soap="http://www.w3.org/2001/12/soap-envelope"soap:encodingStyle="http://www.w3.org/2001/12/soap-encoding"> < soap:Header> ... < /soap:Header> < soap:Body> ... <soap:Fault> ... </soap:Fault> < /soap:Body>< /soap:Envelope>
SOAP request • POST /InStock HTTP/1.1Host: www.example.orgContent-Type: application/soap+xml; charset=utf-8Content-Length: nnn< ?xml version="1.0"?>< soap:Envelopexmlns:soap="http://www.w3.org/2001/12/soap-envelope"soap:encodingStyle="http://www.w3.org/2001/12/soap-encoding"> <soap:Bodyxmlns:m="http://www.example.org/stock"> <m:GetStockPrice> <m:StockName>IBM</m:StockName> </m:GetStockPrice> </soap:Body>< /soap:Envelope>
SOAP response • HTTP/1.1 200 OKContent-Type: application/soap+xml; charset=utf-8Content-Length: nnn< ?xml version="1.0"?>< soap:Envelopexmlns:soap="http://www.w3.org/2001/12/soap-envelope"soap:encodingStyle="http://www.w3.org/2001/12/soap-encoding"> <soap:Bodyxmlns:m="http://www.example.org/stock"> <m:GetStockPriceResponse> <m:Price>34.5</m:Price> </m:GetStockPriceResponse> </soap:Body>< /soap:Envelope>
WSDL • What is WSDL?
WSDL • <message name="getTermRequest"><part name="term" type="xs:string"/>< /message>< message name="getTermResponse"><part name="value" type="xs:string"/>< /message>< portType name="glossaryTerms"><operation name="getTerm"><input message="getTermRequest"/><output message="getTermResponse"/></operation>< /portType>
UDDI • What is UDDI?
UDDI • Discovering and connecting to Web services: • A cross-industry effort driven by all major platform and software developers • Microsoft, IBM and SAP ran a proof of concept business registry for 5 years then handed it over to OASIS (2005) • Now included in many software packages • Not as popular as originally hoped • Many private UDDI registraries
Amazon EC2 • What is Amazon’s Elastic Compute Cloud?
Web Services at Dell • The Dell supply chain: • Assembly plants, vendor-managed hubs, & suppliers • Assembly plants each with their own legacy IS • Assembly plants rely on vendor-managed hubs for inventory which rely on suppliers • Each had to maintain sufficient inventory buffers • Vendor-managed hubs shipped using weekly demand schedules • Dell had a 5-day ship-to target while its suppliers had fulfillment lead-times of up to 45-days • The problem: How to effectively coordinate with its supply chain partners & their information systems
Web Services at Dell • Initial adoption of WS: • Issued manufacturing schedules to assembly plants through their extranet every 2-hours • Interacted directly with inventory mgmt. systems at vendor-managed hubs with instructions to arrange delivery of components to specific loading docks • Results:
Web Services at Dell • Even better supply chains: • Developed an “event management” system to monitor supplier conditions • Automated inquiries & responses are triggered by specific events which lead to adaptation of the supply chain activities • Results:
Lessons • Lessons from Dell’s “pragmatic adoption” path:
Web Services Resources • X Methods: • http://www.xmethods.net/ • WebServices.org • http://www.webservices.org/ • Web Services Journal • http://www.sys-con.com/webservices/