Understanding the Client Access Server Role
Applies to: Exchange Server 2010 Topic Last Modified: 2009-05-18
In Microsoft Exchange 2010, there are five server roles you can install and then configure on a computer that's running Windows Server 2003. This topic provides an overview of the Client Access server role. The Client Access server role supports the Outlook Web App and Microsoft Exchange ActiveSync client applications and the Post Office Protocol version 3 (POP3) and Internet Message Access Protocol version 4rev1 (IMAP4) protocols. The Client Access server role also supports services, such as the Autodiscover service and Web services.
The Client Access server role accepts connections to your Exchange 2010 server from many different clients. Software clients such as Microsoft Outlook Express and Eudora use POP3 or IMAP4 connections to communicate with the Exchange server. Hardware clients, such as mobile phones, use ActiveSync, POP3, or IMAP4 to communicate with the Exchange server. The Client Access server role is required in every Exchange 2010 organization.
Outlook Web App in Exchange 2010 lets you access your e-mail from any Web browser. Outlook Web App is redesigned in Exchange 2010 to enhance the user experience and productivity in many ways. New features, such as smart meeting booking, Microsoft Windows SharePoint Services and Universal Naming Convention (UNC) file share integration, and improvements in reminders and the address book, give you a rich user experience from any computer that has a Web browser. There are two versions of Outlook Web App included in Exchange 2010: the full-featured Premium Outlook Web App client and the new Outlook Web App Light client. Outlook Web App Light is designed to optimize your Outlook Web App experience for mobile phones and slower connections.
For more information about Outlook Web App, see the following topics:
Exchange ActiveSync lets you synchronize data between your mobile phone and Exchange 2010. You can synchronize e-mail, contacts, calendar information, and tasks. Devices that run Windows Mobile software, including Windows Mobile Pocket for Pocket PC 2002, Windows Mobile for Pocket PC 2003, Windows Mobile 5.0 and Windows Mobile 6, are all supported.
If you use a device that has either Windows Mobile 5.0 with the Messaging Security and Feature Pack (MSFP) installed or Windows Mobile 6, your mobile phone will support Direct Push. Direct Push is a technology that's built into Exchange ActiveSync that keeps a mobile device continuously synchronized with an Exchange mailbox.
For more information about Exchange ActiveSync, see the following topics:
Besides supporting MAPI and HTTP clients, Exchange 2010 supports POP3 and IMAP4 clients. By default, POP3 and IMAP4 are installed when you install the Client Access server role. However, the services needed to support POP3 and IMAP4 are disabled. To use POP3 and IMAP4, you must start the POP3 and IMAP4 services.
For more information about POP3 and IMAP4, see the following topics: