Choreography and Orchestration

... I thought, described the same concepts. Here is what people are talking about,

Orchestration always represents control from one party's perspective. This distinguishes it from choreography, which is more collaborative and allows each involved party to describe its part in the interaction.

In orchestration, there’s someone — the conductor — who tells everybody in the orchestra what to do and makes sure they all play in sync.

In choreography, every dancer follows a pre-defined plan — everyone independently of the others.

Orchestration defines procedure and Choreography defines protocol.

Orchestration is generally a full-on execution mechanism for recursive composition of services (aka WS-BPEL). Choreography describes the observable behavior that makes up a contract between a set of peers. It doesn’t say how it is to be achieved just what can be observed. Orchestration is much imperative and choreography declarative. They can work hand-in-hand.

What is the relationship between choreography and web services composition? ... A composite service is a system that arranges existing services in a workflow of some sort (or process if you want) and deploys this arrangement as a service of it’s own. The added value of this system therefore is a previously non-existing functional construct. The key point is that the composite service is indeed a composition and not a simple collection of existing services and that within the composition the service invocations must! be coordinated, e.g. through choreography where the control is centralized. So choreography is a mechanism for coordination (control) in a composite service.

What is Web Services Flow Language? WSFL supports two types of composition and choreography: Flow models: describes business processes; Global models: describe overall partner interactions. Flow models - Describe how to choreograph the functionality provided by a collection of Web services to achieve a particular business need Global models - Describe how a set of Web services interact with each other. ... it was mentioned somewhere that WSFL is superseded by BPEL.

WebService composition can be achieved view two patterns - hierarchical and peer-to-peer. Hierarchical interactions are often found in more stable, long-term relationships between partners, while peer-to-peer interactions reflect relationships that are often established dynamically on a per-instance basis...