Advances in WS-Transaction and WS-Coordination William Cox Ph

Advances in WS-Transaction and WS-Coordination William Cox, Ph. D. OASIS Symposium on Reliable Infrastructure New Orleans 26 April 2004 Cox OASIS Symposium 20040426

Outline • • Motivation and History The Specifications Evolution Specification Techniques Comparisons Standardization Issues Future Summary and References Cox OASIS Symposium 20040426 2

Disclaimer • All opinions are those of the individual author of this presentation, and do not necessarily reflect those of the companies or individuals who are the specification authors. • “My opinion, and welcome to it. ” - apologies to James Thurber Cox OASIS Symposium 20040426 3

Motivations • Support Business process, legacy integration • Designed from the ground up as composable Web services • Tailored to specific needs – WS-AT – tightly coupled, legacy integration, rollback semantics – WS-BA – loosely coupled, long running, compensation semantics – WS-C – Factoring of context management Cox OASIS Symposium 20040426 4

History • XA (X/Open) • OMG Object Transaction Service – And Extended Structures for OTS • XOCP, others • BTP (similar goals but more complex) • WS-CAF (overlapped completion of v 1. 1) Cox OASIS Symposium 20040426 5

Published Specifications • August 2002 Publications – WS-Coordination 1. 0 – WS-Transaction 1. 0 [WS-TX] • September 2003 Publications – WS-Coordination 1. 1 [WS-C] – WS-Atomic. Transaction [WS-AT] • January 2004 Publication – WS-Business. Activity [WS-BA] • Abbreviations – WS-Transaction [WS-TX] refers to WS-AT+WS-BA Cox OASIS Symposium 20040426 6

Specification Relationships v 1. 1 v 1. 0 WSAtomic. Transaction WSBusiness. Activity WS-Transaction WS-Coordination WS-Addressing Cox OASIS Symposium 20040426 7

Structural Evolution v 1. 0 -v 1. 1 • WS-Atomic. Transaction and WS-Business. Activity are now separate specifications – Were subparts of WS-TX 1. 0 • Use of WS-Addressing Endpoint Reference’s opaque Reference. Properties throughout • Editorial and readability improvements • Separate publication of WS-AT and WS-BA Cox OASIS Symposium 20040426 8

Technical Evolution v 1. 0 -v 1. 1 • General – Adopted opaque Endpoint Reference from WS-Addressing • v 1. 0 “roll your own” contributed to WS-Addressing requirements – Updated and enhanced security considerations, policy • WS-AT – Renamed to Volatile 2 PC, Durable 2 PC – Complete state tables • WS-BA – Named more consistently • Business. Activity. With. Coordinator. Completion • Business. Activity. With. Participant. Completion – Renamed some states – Complete state tables Cox OASIS Symposium 20040426 9

Specification Techniques • State reduction through simplification – Factored WS-Coordination – Didn’t try to view state of entire interaction • Only the coordinator and participant separate views • Some additional care for consistency designed in – Acknowledge then ignore “state smear” • Broad applicability for WS-Coordination – WS-AT, WS-BA, other coordinations Cox OASIS Symposium 20040426 10

Some Comparisons • WS-C/WS-TX – WS-Coordination specified as simple algorithm – WS-AT has 7 states – WS-BA has 8/9 states • BTP has 28 Superior, 36 Inferior states – But includes ~ WS-C x WS-BA states in one machine Cox OASIS Symposium 20040426 11

Some Comparisons (continued) • WS-CAF—Bookkeeping difficult – Builds on context mgt protocol WS-CTX, as does WS-TX – Atomic has 8 states and 14 messages – LRA has many sub-protocols (total of 40 messages) Cox OASIS Symposium 20040426 12

Another Comparison • Pages of specification – BTP: 188 pages – WS-CAF base docs 240 pages – WS-Coordination+WS-AT+WS-BA 59 pages • Does reflect time needed to read and understand Cox OASIS Symposium 20040426 13

Standardization Issues • Use of WS-Addressing requires standardization of at least Endpoint Reference – This is also an issue for the new WS-Resource Framework and WS -Notification TC base documents • Factoring useful if not overdone – WS-TX/WS-C factoring seems about right • Specify, demonstrate interoperability, iterate – Focus on interoperable implementations important – When and in which cycle? – More mature specs into standardization process vs buy-in Cox OASIS Symposium 20040426 14

The Future • Author companies have committed to submitting to a standards organization • Feedback meeting March 2004 – See references • Comment license required – So can maintain royalty-free approach to these specs • Interoperability event in planning Cox OASIS Symposium 20040426 15

Summary • WS-Transaction and WS-Coordination simple enough, rich enough • Composable web services target level • Specifications at the right level – Reasonable number of states – Reasonable number of protocols – Comparatively lower complexity than competing specs • Progressing to interoperability testing and submission to a standards organization Cox OASIS Symposium 20040426 16

References • • • WS-Coordination WS-Atomic. Transaction WS-Business. Activity WS-Addressing IBM Links http: //www-106. ibm. com/developerworks/views/webservices/standards. jsp Alphabetization problems--some under “WS-”, some under “Web Services” • Microsoft Links http: //msdn. microsoft. com/library/default. asp? url=/library/en-us/dnglobspec/html/wsatspecindex. asp • BEA Links http: //dev 2 dev. bea. com/technologies/webservices/standards. jsp Interoperability and Feedback http: //www-106. ibm. com/developerworks/offers/WS-Specworkshops/ws-tx 200402 post. html http: //msdn. microsoft. com/webservices/community/workshops/transactionws 032004. aspx Cox OASIS Symposium 20040426 17

References (continued) • WS-CAF (Arjuna, Fujitsu, Iona, Oracle, Sun) July 2003, OASIS TC – http: //www. oasis-open. org/committees/tc_home. php? wg_abbrev=ws-caf • BTP OASIS TC http: //www. oasis-open. org/committees/tc_home. php? wg_abbrev=business-transaction – BTP 1. 0 http: //www. oasis-open. org/committees/download. php/1184/2002 -06 -03. BTP_cttee_spec_1. 0. pdf – BTP Primer http: //www. oasis-open. org/committees/download. php/2077/BTP_Primer_v 1. 0. 20020605. pdf Cox OASIS Symposium 20040426 18