A2A

Application 2 Application Services

Application 2 Application Services
Application 2 Application Services is services which orchestrates services from several applications, typically asynchronous and workflow-backed. I.e. a Auction type request against a set of suppliers or an booking/order/delivery process.

Suggestion for a more presise definition
An A2A service is a service which is responsible for collaboration between several human or automated actors.

Characteristics

Two types:

Process Services

Services orchestrated to produce real business value
Workflow-oriented processes
Orchestrated functionality from several services
ACS/CS services as Business/Domain Objects
External applications for sub-processes & tasks
Long running processes
Should not have any long-running transactions
Could (should) have cache (state full)

Application Integration Service Endpoints

Services which integrate and map against external application endpoints
Should (internally) provide for SLA and contractual requirements (via cache, rebind, fail-over and such)
Works as an external data anti-corruption layer for external application endpoints to reduce dependencies and facilitate evolve ability

Patterns for Application 2 Application Services

Application 2 Application Services

Technology/Implementation strategy (Java)

Technology, implementation and products

Pick your favorite JEE/ESB/SOA platform vendor
- Sun, IBM, Oracle
Choose your favorite open source ESB/SOA platform
- OpenESB or another Open Source JBI container
- write a simple admin framework (upgrade tool support)

Technology/Implementation strategy (.NET)