Web Services CS651/551 Federated Trust Systems Alfred C. Weaver

Web Services CS651/551 Federated Trust Systems Alfred C. Weaver

History Structured programming Object-oriented programming Distributed computing Electronic data interchange World Wide Web Web services

Who Was First? What company first proposed the web services concept? Hewlett-Packard's e-Speak in 1999 was an enabler for e-services Microsoft introduced the name "web services" in June 2000 MS "bet the company" on its web services strategy now every major vendor is a player

Open, Standard Technologies XML – tagging data such that it can be exchanged between applications and platforms SOAP – messaging protocol for transporting information and instructions between applications (uses XML)

Open, Standard Technologies WSDL – a standard method of describing web services and their specific capabilities (XML) UDDI – defines XML-based rules for building directories in which companies advertise themselves and their web services

Advantages Open, text-based standards Modular approach Inexpensive to implement (relatively) Reduce the cost of enterprise application integration Incremental implementation

Real Web Services UC-Berkeley Unified Communications Technical Project unify email, voice, and fax into in-boxes accessible from cell phones, PDAs, or email clients Eastman Chemical Company distributors access chemical catalog in real-time and push info to customers

Real Web Services Accenture Live Information Models stock traders access real-time information from a single terminal Dollar Rent-a-Car Southwest Airlines Southwest runs Unix Dollar runs MS Windows Dollar turned its system into a web service

More Examples Web service broker sites www.xmethods.net www.salcentral.com

Online Resources www.deitel.com www.w3.org web services, C# World Wide Web Consortium (W3C) recommendations, news, mission, FAQs www.w3.org/History.html history of computing and internet from 1945 to now

Online Resources www.webservices.org news, standards, vendors, platforms, products, applications, case studies, security mechanisms www.webservicesarchitect.com online journal for web service developers; tools, vendors, business models, additional resources

Online Resources www.ws-i.org web service interoperability organization (WS-I); promote interoperability among services created in different languages and platforms; white papers, news, FAQs

Online Resources www.xml.com/lpt/a/2002/02/06/ webservices.html "Web Service Pitfalls": limitations, unresolved security issues www.webservices.org/print.php? sid 201 "Web Services—A Reality Check": transactions, security, QoS

The Big Picture UDDI Registry WSDL Document Registry refers client to WSDL document WSDL provides data to interact with web service Client queries registry locate service Client to accesses WSDL document Web service returns SOAP-message response Client sends SOAP-message request Client Web Service Code

XML Developed from Standard Generalized Markup Method (SGML) XML widely supported by W3C Essential characteristic is the separation of content from presentation XML describes only data Any application that understands XML can exchange data

XML XML parser checks syntax If syntax is good the document is well-formed XML document can optionally reference a Document Type Definition (DTD), also called a Schema If an XML document adheres to the structure of the schema it is valid

SOAP SOAP enables between distributed systems SOAP message has three parts envelope – wraps entire message and contains header and body header – optional element with additional info such as security or routing body – application-specific data being commuicated

WSDL Web services are self-describing Description is written in WSDL, an XML-based language through which a web service conveys to applications the methods that the service provides and how those methods are accessed WSDL is meant to be read by applications (not humans)

UDDI UDDI defines an XML-based format that describes electronic capabilities and business processes Entries are stored in a UDDI registry UDDI Business Registry (UBR) "white pages" – contact info, description "yellow pages" – classification info, details "green pages" – technical data uddi.microsoft.com

OASIS Not competition to W3C Ensure that businesses acquire ebusiness tools that meet their needs United Nations Centre for Trade Facilitation and Electronic Business produced Electronic Business XML (ebXML)

More Info www.w3.org/2002/ws www.uddi.org explanation; business benefits www.oasis-open.org web services activity technical work and standards www.ebxml.org technology and business benefits

Web Services Security Architecture WS-Secure Conversation WS-Policy WS-Federation WS-Authorization WS-Trust WS-Privacy WS-Security SOAP

WS-Security Describes how to attach signature and encryption headers to SOAP messages; how to attach security tokens such as X.509 certificates and Kerberos tickets WS-Secure Conversation WS-Policy WS-Federation WS-Authorization WS-Trust WS-Privacy WS-Security SOAP

WS-Policy Describes the capabilities and constraints of the security and business policies on intermediaries and endpoints WS-Secure Conversation WS-Policy WS-Federation WS-Authorization WS-Trust WS-Privacy WS-Security SOAP

WS-Trust Framework for trust models that enables web services to interoperate securely. WS-Secure Conversation WS-Policy WS-Federation WS-Authorization WS-Trust WS-Privacy WS-Security SOAP

WS-Privacy Model for how web services and requesters state privacy preferences and organizational privacy practice statements WS-Secure Conversation WS-Policy WS-Federation WS-Authorization WS-Trust WS-Privacy WS-Security SOAP

WS-SecureConversation Manage and authenticate message exchanges between parties, including security context exchange and establishing and deriving session keys WS-Secure Conversation WS-Policy WS-Federation WS-Authorization WS-Trust WS-Privacy WS-Security SOAP

WS-Federation Manage and broker trust relationships in a heterogeneous federated environment, including support for federated identities WS-Secure Conversation WS-Policy WS-Federation WS-Authorization WS-Trust WS-Privacy WS-Security SOAP

WS-Authorization Manage authorization data and authorization policy. WS-Secure Conversation WS-Policy WS-Federation WS-Authorization WS-Trust WS-Privacy WS-Security SOAP