The Exchange Developer Roadmap has been discussed by more authoritative sources before leading up to the release of Exchange 2010. I’d like to revisit this roadmap and take it from where Jason left off, going forward into Exchange Online in Office 365. For enterprise customers this is important to understand – if you are upgrading from Exchange 2003 to 2010 or Online then many applications that touch Exchange today will require an upgrade to the “modern” Exchange APIs. For an ISV looking at these API sets will help you understand what APIs you need to leverage to support the versions of Exchange you’re targeting.
When I talk about this roadmap or evolution of Exchange development, I typically do so by grouping the APIs in six categories:
Let’s take a high-level walk through these groups from Exchange 2003 to Exchange 2010 and see how the APIs evolve over time and how they are different between on-premises and online…
Exchange Online (BPOS):
Exchange Online (Office 365):
I’ll get into more detail about this evolution with a discussion of online service descriptions in the coming weeks. I’ll also talk about how the features and APIs available in each version affect product planning for ISVs that want to support Exchange Online as well as Exchange on-premises.