Exchange 2013 Server Role Architecture

The Past: Exchange 2007 and Exchange 2010

In 2005, we set out developing Exchange 2007. During the preliminary planning of Exchange 2007, we realized that the server architecture model had to evolve to deal with hardware constraints, like CPU, that existed at the time and would exist for a good portion of the lifecycle of the product. The architectural change resulted in five server roles, three of which were core to the product:

1. Edge Transport for routing and anti-malware from the edge of the organization
2. Hub Transport for internal routing and policy enforcement
3. Mailbox for storage of data
4. Client Access for client connectivity and web services
5. Unified Messaging for voice mail and voice access

Figure 1: Server role architecture in Exchange 2007 & Exchange 2010

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