Outlook Anywhere Scalability with Outlook 2007, Outlook 2003, and Exchange 2007
Outlook Anywhere scalability and client network traffic are two areas that generate many questions about the number of connections Outlook makes and sustains to an Exchange server. This area is frequently the subject of discussion when site consolidation is being discussed which also raises the issues of network costs and Transmission Control Protocol (TCP) connection limits. The TCP connection limitations are largely hit by hosting companies and large enterprise customers who force all MAPI connectivity through RPC over HTTP (RCP/HTTP). In the following sections we will cover each of these areas in detail to help show the behavior you can expect to see when using Outlook Anywhere in your Exchange 2007 deployment.
Outlook Anywhere Scalability with Outlook 2007, Outlook 2003, and Exchange 2007 whitepaper
Also check out the Client Network Traffic post on the Exchange Teams Blog