If my understanding is correct, in Exchange 2010 clients Outlook clients used to connect to the CAS using MAPI (which used TCP) which is also referred to as RPC over TCP.
In Exchange 2013, clients must connect to the CAS using RPC over HTTPS.
What I don't understand is how MAPI fits into this. Is this effectively MAPI over HTTPS? What is the correlation between MAPI and RPC?