During the recent Microsoft Exchange Conference (MEC), Microsoft released their latest iteration of the Preferred Architecture (PA) for Exchange. The guiding principle behind the design is simplicity and it is highly influenced by Office 365.
The PA design assumes that customers have two data centres and that both will be used concurrently for client connections. The PA also assumes that clients are distributed between the two data centres or are connecting from external locations. If this is not the case, then customers would need to modify the design to fit their needs.
Although many customers will be designing from a different baseline, some of the recommendations will still apply so it’s worthwhile reading. The blog post from Microsoft on the new PA can be found at: http://blogs.technet.com/b/exchange/archive/2014/04/21/the-preferred-architecture.aspx