NBA 600: Session 25 IT and the General Manager New Technologies: Web Services 22 April 2003 Daniel...
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Transcript of NBA 600: Session 25 IT and the General Manager New Technologies: Web Services 22 April 2003 Daniel...
NBA 600: Session 25IT and the General Manager
New Technologies: Web Services22 April 2003
Daniel Huttenlocher
2
IT and Your Business
What should a general manager today know about information technology?– IT investment has potential strategic as well as
operational value– The best IT investments improve products or
services not just reduce costs• Possible because of rapid IT improvements• Applies to both internal projects and purchases
– Proposed costs and benefits need to make business sense• Takes effort both by IT and business experts
3
What To Do
An IT-aware general manager should– Not necessarily be a technology expert
• If an expert, be sure to trust other experts and to make business not IT motivated decisions
– Actively look for areas where IT could improve products/services while lowering costs• Also respond to and evaluate proposals from
others that meet these criteria
– Develop good working relationships with trusted technology experts• Partners not support roles• Mutual education
4
Emerging Technologies
Investigate some new technologies– In context of making effective general
management decisions
Web services receiving a lot of attention over the past couple years– Many companies racing to deploy– Lots of acronyms: XML, SOAP, … – Software platforms such as J2EE and .net– Pre-existing Web services– Business risks and benefits– Deployment costs
5
What Web Services Are
Definition of a Web service– Paraphrased from W3C (w3.org)
• A software system, accessible via the Web, with interfaces described using XML, accessed by other software systems using XML-based messages conveyed by internet protocols
IP Network
Request
XML responseServiceProvider
ServiceRequestor
6
Web Site vs. Web Service
API (Application Programming Interface)– To be used by other software not a person– Separates the display/layout from content
• No need to change processing because layout changes!
HTML for expressing display of content whereas XML for content only
Network
HTTP request
HTML response
ServerClient
(Browser)
7
Business Case for Web Services
Makes your business information accessible for others to use on their sites– E.g., Fedex or UPS tracking information on e-
commerce Web site– Can be governed by terms of use and require
authentication/authorization• E.g., amazon.com only access their shipping info
Enable your customers to place orders from their systems– E.g., large (corporate) customers– Supply chain integration
8
Risks of Web Services
Making information accessible to those outside the firm– Careful consideration of what access to provide
and to/from whom– Appropriate authentication and authorization
policies and implementations
Maturity of underlying technology– Risks of failure or errors in what become
critical systems
Not acting and having your competitors provide better services
9
Some Web Services Offerings
10
Ebay Web Services
Automation of– Listing items– Monitoring auctions– Searching– Feedback
11
Not a Specific Technology
Web services simply refers to an architecture in which– Software systems communicate directly– Communication uses XML-based messages
over internet protocols• Can use regular HTTP (Web) server such as
Apache
Does not require– Use of higher level standards such as SOAP
and WSDL– Use of particular implementations such as J2EE
or .net
12
XML
Simple, extensible text format for exchange of data– Intended to enable good description of data– More of a framework than actual format
• Needs to have “tags” defined by a schema
Extremely valuable for replacing many non-standard data exchange formats– Standard “parsers” convert text to computer-
accessible format– A simple idea that can make data interchange
work better – but not rocket science
13
Basic XML Example
A simple personnel record, with name, address, employee number, salary– “Fields” must be defined in a schema
<employee><name><first>Jane</first><last>Doe</last></name><address><number>14</number><street>Main Street</street><city>Ithaca</city><state>NY</state><zip>14850</zip></address><id_number>142996</id_number><salary>72,000</salary></employee>
14
What XML Gets You
Great; both systems use XML format– Analogy: knowing the same language
(grammar, etc.) – saves a lot!
Still need to know how the systems communicate– E.g., using HTTP, SOAP over IIOP, etc.– Analogy: on the phone, internet, in person, etc.
Still need to know the vocabulary– Provided by Schema, but need to know how to
use the resulting data– Analogy: meaning of special-purpose terms
15
Full Web Services Architecture
IP Network
DiscoveryAgency
ServiceProvider
ServiceRequestor Interaction
(Using SOAP)
Publish(UDDI/WSDL)
Find(UDDI/WSDL)
16
Full Web Services Stack
Layers involved in full Web services architecture– Note the “business issues” from a general IT
architectural perspective
17
SOAP
An XML-based means of describing communication between systems– Works with various network protocols
• E.g., HTTP, SMTP, FTP, RMI/IIOP or proprietary messaging protocols such as MQSeries
– SOAP intended to standardize description of what is in a message sent between systems• Can simply use network protocols directly but
not “self describing”
– Hype often ahead of value with SOAP• More variation in data than in message format
so more important to use XML for data itself
18
WSDL/UDDI
XML-based means of describing and discovering Web services
Part of the Web services architecture is that there should be service directories– Services and descriptions can be looked up
• E.g., find me a package delivery service
– Description involves how to access service and what messages can be sent
Powerful vision, but still actively evolving– Today known which systems will interact with
one another – not highly dynamic
19
Web Services Software
Two application development frameworks make easier to deploy Web services– J2EE from Sun, based on Java
• Also supported by IBM, Oracle and BEA• Proprietary extensions from each vendor
– .net from Microsoft, based on CLR• CLR: common language runtime
Language independent but primarily new language C# and Visual Basic
• Wide adoption in Microsoft developer community
In practice, many are using both
20
Recent Study
Gartner survey from September ’02– 44 consulting and systems integration firms– Reported in Information Week, 2/5/03
Top 3 platforms targeting for Web services– 58% .net– 40% IBM WebSphere (J2EE)– 31% Oracle (J2EE)– Sun fourth place
Survey of 140 companies similar results– Smaller companies more likely to use .net– Larger more likely to use J2EE or both
21
What’s Meant by Web Services
Most companies still using Web services within the enterprise– Some starting to offer services to outsiders
• Beyond technology leaders like FedEx, Google, Amazon, Ebay
Generally using XML for inter-system communication over HTTP
Usage of SOAP and WSDL still low– In Feb. 2002 was “miniscule”– Currently around 20% report using at least one
22
Full Web Services Architecture
IP Network
DiscoveryAgency
ServiceProvider
ServiceRequestor Interaction
(Using SOAP)
Publish(Using WSDL)
Find(Using WSDL)
23
Today’s Web Services Architecture
IP Network
ServiceProvider
ServiceRequestor Interaction
(Using XML over HTTP)
24
Management Decisions
Vendors and platforms– Unix/Java or Microsoft shop (often both)
• J2EE or .net (or both)
– Currently using• Other trends driving these choices within firm
What are potential customers using and how much influence over their choices– Or compatibility across vendors
How far up the Web services stack– Is minimum for the business purpose– Is desirable for future compatibility