IT Standards - Politics and Practicalities. Andrew Watson VP & Technical Director, OMG

Transcription

1 IT Standards - Politics and Practicalities Andrew Watson VP & Technical Director, OMG andrew@omg.org

2 Why Standards? Standardisation vital in modern IT - Once (c. 1960) everything could be bought from one source - Today manufacturers are mostly system integrators - Closed Powerbook G4 has Motorola CPU, Fujitsu RAM, Matshita CD/DVD, Hitachi hard disk, CSR Bluetooth, Broadcom g, V.24 modem by?, Ethernet chip by? - End-user also integrator (Ethernet, Nubus, PC-card, USB...) Standards define structure & behaviour of interfaces - Allow third parties to build systems - (Should) provide maximum latitude on implementation Standards in practice 2

3 Introducing OMG Computer industry forum for creating open integration standards - UML, SysML, BPMN and related modelling specifications - CORBA integration platform & many related specifications An industrial consortium with vendor and user members - Implementation must be available from OMG member Specifications freely available to all - Visit Decisions taken by members Standards in practice 3

4 88 Solutions Adaptive Adobe Alcatel Artisan BAE Systems BEA Systems Boeing Borland CA Capgemini Credit Suisse CSC Worldwide Membership Daimler Deere & Co. DoCoMo EBI EDS EFF Eurocontrol EuroSTEP Fujitsu GCHQ G. Dynamics Gnome Fndn. HDMA HP Hitachi IBM IDS Scheer IONA K dy Carter Lockheed Lombardi MEGA Mentor G ics MITRE Motorola NASA NEC NIST Nokia Northrop OIS Oracle OSD Penn Nat l Promia PrismTech Raytheon Red Hat Rockwell SAP SAS Institute Siemens Sparx Systms SWIFT Telelogic Thales Toshiba TCS Unisys US Nat. Arch. VHA VISA Standards in practice 4

5 Similar organisations (1) Internet Engineering Task Force (IETF) - Publishes RFCs (standards) for the internet - IPv4, IPv6, TCP, EGP, BGP, RIP, HTTP, SMTP, FTP... - Run by Internet Architecture Board (IAB) - Part of US Govt. until early 90s, now under Internet Society World Wide Web Consortium (W3C) - Makes recommendations (standards) for the web - HTML, CSS, XML, XML Schema, SOAP, SVG, XSLT international offices, founded by Tim Berners-Lee Standards in practice 5

6 Similar organisations (2) Organization for the Advancement of Structured Information Standards (OASIS) - Makes standards for information representation - DocBook, DITA, OpenDocument, DCML, LegalXML, BPEL... - Started as SGML Open in 93, became XML-focussed in 98 The Open Group - Owns UNIX trademark, does certification programmes - TOGAF, X Windows, Motif, POSIX, DCE, LDAP, - Merger of Open Software Foundation and X/Open in OSF set up in 1988 by Unix vendors, created OSF/1 Standards in practice 6

7 Similar organisations (3) ECMA International - Formerly European Computer Manufacturers Association - CD-ROM (became ISO 9660), C#, C++/CLI, ECMAScript (JavaScript), Microsoft Office Open XML - Sun submitted, and then withdrew Java - More than 2/3 of ECMA standards went on to become international standards A host of others, more or less specialised - IEEE, USB Implementers Forum, InterNational Committee on Information Technology Standards (INCITS) - SCSI... Standards in practice 7

8 De-jure standards Individual counties have national standards bodies - typically independent but recognised by government - British Standards Institute (BSI) - Deutsches Institut für Normung (DIN) - American National Standards Institute (ANSI) National bodies make own standards, represent their countries at international standards bodies: - International Organization for Standardization (ISO) - International Electrotechnical Commission (IEC) - International Telecommunications Union (ITU-T) Standards in practice 8

9 De-jure vs. de-facto De-jure standards carry weight - Governments & often demand de-jure stds compliance - Usually slow to create, lots of committee work De-facto standards are what everyone uses - MS Word format, x86 instruction set, VGA, PDF, Javascript - Usually initially owned by one company, sometimes handed over to (more-or-less) independent organisations Standards consortia seek a happy medium - Fast (-ish), widely accepted, but not owned by one company - Anti-trust issues Standards in practice 9

10 Intellectual Property & Politics Closed standards exist, but most prefer Open... - Freely obtain documentation (Buy? Sign licence?) - Freely implement (Patents? If so, licencing terms?) - Freely sell/give away implementations - Freely modify & circulate original standard (usually not) Publisher usually retains copyright on document - US DMCA made it possible to copyright abstract interface Patent licencing a minefield - Spectrum: unencumbered, free licence, RAND, all bets off - RAMBUS case Standards in practice 10

11 Standards for software design Software systems the most complex artifacts created by man - Temporal dependencies, discontinuous behaviour Software, like physical structures, needs blueprints - Abstract away detail to give the high-level view - Represent complex relationships for deep understanding - Represent static, dynamic and causal relationships Better design -> faster time-to-market, better quality, lower cost - The later you catch a bug, the more expensive it is Analysis and Design notations are the means to draw the plans Standards in practice 11

12 Design standards in practice - UML OO modelling languages (& books) multiplied in the early 90s - Wirfs-Brock (1990) - Coad/Yourdon (1991) - Booch at Rational (1994) - Rumbaugh s OMT at GE labs (1991, 1996) - Odell/Martin (1994) - Jacobson at Ericsson (1992, 1995) - Shlaer/Mellor recursive design (1997) By 1994 chaos ruled - Similar concepts, incompatible notations, few support tools Standards in practice 12

13 UML - unification Late 94: Rumbaugh joins Booch at Rational Early 95: Jacobson & Soley begin push for method standards - All major players represented at OMG meeting Jun Mary Loomis leads ADTF, chartered to deliver standard Late 95: Rumbaugh & Booch produce Unified Method Jacobson joins Rational - the Three Amigos 1996: OMG issues RFP, Amigos release Rational UML 0.9 & 0.91, establish UML Partners to work on UML 1.0 Jan. 97: OMG meeting in Tampa evaluates RFP submissions Standards in practice 13

14 UML standard - finale Jan. 97 submissions from: - Rational & partners (DEC, HP, IBM, MS, Oracle, Unisys, etc.) - IBM/Objectime, Platinum, Ptech, Taskon/Reich, Softeam All submitters agreed common approach during Nov. 97: UML 1.1 adopted by OMG Revisions under OMG process produce UML 1.2 (formatting cleanup), 1.3 (Mar 2000), 1.4 (Step 2001), 1.5 (Mar 2003) UML became ISO/IEC 19501:2005, Jan Standards in practice 14

15 UML today UML market grew at ~ 20% PA through the IT recession Over 2/3 of organisations now use UML (BZ research, Aug. 04) - 80% plan to use UML in future - Dozens of tools - Over 100 UML-related books - Training widely available - UML certification UML 2.0 published July 05, already widely used, on its way to ISO Standards in practice 15

16 Other OMG Modelling Standards Meta-Object Facility (MOF) - Foundation on which all OMG modelling specifications build XML Metadata Interchange (XMI) - Common standard for exchanging all MOF-based models Semantics of Business Vocabulary & Rules (SBVR) - For defining business terms and how they are related Business Process Modelling Notation (BPMN) - Published by BPMI in 2005 now merged into OMG Business Motivation Model (BMM), and others... Standards in practice 16

17 OMG metamodel and syntax families MOF Meta-meta model (Language) Model Exchange via XML Metadata Interchange (XMI) Common Warehouse Metamodel UML Metamodel Business Process Metamodel Business Rules Metamodel Organisation Structure Metamodel UML Visual syntax UML Activity syntax BPMN syntax Structured English Org charts (?) Standards in practice 17

18 OMG Meta-Object Facility (MOF) Standardised in parallel (and in cooperation) with UML Foundation for OMG repository (meta data) architecture - Model, design and implement metamodels - Provides IDL, Java mappings to automate generation of concrete interfaces for specific metamodels XMI provides for storage/interchange of MOF models via XML - Capable of being common exchange format for all OMG modelling specifications Standards in practice 18

19 Business Process Modelling Notation Business Process Modelling Initiative established August Objective: create an XML business process language for both modelling & executing business processes - Result: Business Process Modelling Language (BPML) - Outflanked by IBM, Microsoft, BEA merging their early XML BPLs as Business Process Execution Language (BPEL) Happily, BPMI also worked separately on a graphical Business Process Modelling Notation (BPMN) - Similar notational conventions to UML 2 activity diagram - Originally intended to map onto BPML - Now adapted to map onto very-similar BPEL4WS Standards in practice 19

20 Business Process Modelling Notation (cont.) V 1.0 published May Written by Steven White (IBM) & 28 authors from 24 orgs. Provides visual syntax for Business Processes understandable by both technical and business users - For modelling all business processes, not just automateable ones - End of Business Process Modelling wars in sight? - No metamodel, no standard exchange format specified -... now being rectified through OMG Business Process Definition metamodel process Standards in practice 20

21 BPMN example Supplier Financial Institution Sales Distribution Authorise credit card + Authorise payment Process order + Pack goods Ship goods Standards in practice 21

22 Semantics of Business Vocabulary & Rules MOF metamodel for vocabularies & rules describing business - Designed from the start to be used with MDA - As for BPMN, applies to whole business, not just IT Business rule: Rule that business can enact or revise - Based on first-order predicate logic, with limited extensions Also precise, non-normative human-readable text syntaxes - Structured English - RuleSpeak - Business Rule Solutions established notation Specification written in terms of itself (in Structured English) Standards in practice 22

23 Structural & Operative Rules Structural rules are definitions - how a business chooses to organise the things it deals with - A Car Hire Customer has at least one of the following: A Reservation An in-progress car hire A car hire completed within the last 5 years Operative Rules govern conduct of business activities -... and therefore can be violated by the people involved - A customer who appears drunk must not be given possession of a hire car Standards in practice 23

24 Example operative rules in Structured English It is obligatory that each rental car is owned by exactly one branch. Quantifier Fact type Object type Modality Object type Quantifier It is obligatory that at the actual return date/time of each in-country rental and each international inward rental the local area of the return branch of the rental owns the rented car of the rental. Standards in practice 24

25 Why standards consortia work Users like open standards - Avoids vendor lock-in - Externality An externality occurs when a decision causes costs or benefits to third party - I care what computer/dvd/digital music format you use So what motivates vendors to participate? - Cynical answer - in any market niche top supplier hates open standards, all others love them - Less cynical... all vendors are also customers - Creating standards in a market is not a zero-sum game Standards in practice 25

26 A non-zero-sum game Classic prisoner s dilemma Two prisoners held separately, police have insufficient evidence for conviction, so offer each the same deal - Testify against the other and the other remains silent > betrayer goes free and the silent accomplice gets 10 years - Both stay silent > both get 6 months for a minor charge - Both betray the other > each gets 5 years sentence Each must choose whether to talk or stay silent, neither knows what choice the other prisoner will make Dilemma: How should self-interested prisoners act? Standards in practice 26

27 Iterated prisoners dilemma Prisoners dilemma not a zero-sum game - If both cooperate, total punishment is minimised Iterated prisoners dilemma: played repeatedly against same opponents with memory of previous outcomes Robert Aumann showed rational players in indefinitely long games can sustain the cooperative outcome (1959 paper) Robert Axelrod ran iterated prisoners dilemma tournament between computer programs ( The Evolution of Cooperation ) - Greedy strategies did poorly, altruistic strategies did well, best was tit for tat Standards in practice 27

28 Evolution of cooperation OMG and similar standards consortia are closed communities - Same individuals often represent companies for years - Individuals sometimes move companies to stay involved! Cooperation evolves between individual representatives of competing companies Representatives who cheat tend to be excluded from working in the (self-organising) groups that create specifications As in iterated prisoners dilemma, attempts to cheat offer short-term reward, but long-term disadvantage Standards in practice 28

29 Summary Standards are essential in the IT business De-facto standards spring up quickly, usually single-vendor De-jure (international) standards often slow to make, sometimes very academic Industry standards consortia (like OMG) aim for happy medium Different meanings of Open Economics and game theory help explain why it works Standards in practice 29