When working through the book "Implementing Domain Driven Design" by Vaughn Vernon, I have been unable to gain a good grasp on what a bounded context actually is.
The book defines a bounded context as "a conceptual boundary where a domain model is applicable. It provides Ubiquitous Language that is spoken by the team and expressed in its carefully designed software model" (the "Guide to this Book" prefacing section). This definition would make it sound as though a bounded context is the model and language of a subdomain, where that subdomain may happen to be the core domain (which seems like it ought to be referred to as a "core subdomain", but that is another discussion...). This still leaves some ambiguity as to what a bounded context provides. Is it a grouping of one or more subdomains? If only one subdomain corresponds to a bounded context, what is the bounded context actually telling us?
Chapter 3 of the same book, however, refers to the integration techniques between bounded contexts. This, however, would seem to imply that the bounded contexts are actually software systems or artefacts of some variety.
Martin Fowler briefly discusses the idea of a bounded context (http://martinfowler.com/bliki/BoundedContext.html), but does not really clarify the issue.
At the end of the day, what is a bounded context? Is it a grouping of subdomains? The model and language for a subdomain? The implementation of a subdomain? Without these answers, it seems rather difficult to understand how to decompose a real-life problem space into bounded contexts.