· Exchange 2013 SP1 will add Windows Server 2012 R2 as a supported operating system for Exchange Server 2013 with SP1;
· Support for S/MIME in OWA will be brought back in SP1. With SP1 customers will have S/MIME support across Outlook, Exchange ActiveSync clients, and OWA;
· The Edge Transport server role for Exchange Server 2013 will be available with SP1.
· Fixes and Improvements. SP1 will include fixes and improvements in several areas. SP1 is the first service pack issued in the new Exchange Server cumulative update release model - thus SP1 is essentially CU4. The installation of SP1 will follow the same process as the prior Exchange 2013 CU releases. SP1 will include all fixes included in previously released cumulative updates for Exchange 2013.
· MapiHttp is the new communication mechanism added to later builds of Microsoft Exchange Server 2013 and Microsoft Outlook 2013. The plan is to add the functionality to Microsoft Outlook 2010 in a future build. You may also see the new MapiHttp feature referred to internally as the Exchange HTTP Transport or by the internal code name Alchemy. The new MapiHttp transport protocol replaces the older RPC/HTTP (RPC over HTTPS) protocol. This is in an effort to improve the reliability and stability of the Outlook/Exchange connection by removing the dependency on the Microsoft Remote Procedure Call (RPC) communication mechanism;
· DLP Policy Tip support in OWA.