Microsoft Exchange Server Architecture and Core Roles
Microsoft Exchange Server Fundamentals
Microsoft Exchange Server is calendaring software, a mail server, and a contact manager developed by Microsoft. It is a server program that runs on Windows Server and is part of the Microsoft Servers line of products.
Key Features and Functionality
Advantages of Using Exchange Server
- Incoming Mail and Sent Items are always available on multiple computers and/or Webmail (mail is synced between the mail server and client).
- Supported by most current mobile devices.
- Calendar and Contacts are synced as well.
Limitations
- Not all computer mail clients support MS Exchange Mode.
- Unless configured otherwise, offline consultation is not available.
Understanding Exchange Server Roles
MS Exchange includes numerous roles for creating an Exchange organization. Previous versions of Exchange had all of the functionality in a single role. This did not hold well for scalability. The functionality was split in order to place individual functions on different servers if required. This allowed Exchange to scale from small to large environments.
There are 5 roles necessary for creating an Exchange organization:
- Mailbox Server Role
- Client Access Server Role (CAS)
- Hub Transport Server Role (Bridgehead)
- Edge Transport Server Role (Gateway)
- Unified Messaging Server Role
Mailbox Server Role
The Mailbox Server Role may be combined with the Client Access Server and/or Hub Transport roles in Exchange Server 2010, regardless of whether or not the mailbox server participates in a Database Availability Group. Mailbox is a good name for the core Exchange server; it stores all the email.
Client Access Server Role (CAS)
The CAS is one of five server roles in Exchange 2010. The Client Access Server (CAS) is a server role that handles all client connections to Exchange Server 2010. The CAS supports all client connections to Exchange Server from Microsoft Outlook and Outlook Web App, as well as ActiveSync applications. The CAS also provides access to data in Exchange calendars. It must be installed in every Exchange Server organization and on every Active Directory (AD) site that has the Exchange Mailbox Server Role installed.
Hub Transport Server Role
The Hub Transport server transfers messages between mailboxes. The Hub Transport Server Role handles all email flow inside the organization, applies journaling policies, and delivers messages to the recipient’s mailbox. The Hub server must be deployed in every Active Directory site that contains other Exchange Server 2007 roles. The Hub Transport Server Role stores all its configuration information in Active Directory. This information includes transport rules settings, journal rule settings, and connector configurations.
Benefits of Microsoft Exchange
With Exchange, users can access their mailboxes from wherever they go, with full support for Outlook, a premium web browser-based experience, and access from a wide range of mobile devices. Key benefits include:
- Storage Options: More storage options make it possible to offer users low-cost, large mailboxes so they can access all their essential information in one place.
- Calendar Sharing: Allows users to share free/busy information with colleagues, even if they work at another company.
- Compliance and Discovery: Email archiving, eDiscovery Search, retention policies, and legal hold help you preserve and discover data.
- Security: Security policies let you create approved mobile device lists, enforce PIN lock, and remotely wipe data from lost phones.
- Deployment Flexibility: Choice of deployment options including Exchange Server on-premises, Exchange Online in the cloud, and hybrid deployment options.