Exchange 2000 Scalability and Availability Solutions

A primary goal for Exchange 2000 is to meet the massive scalability and reliability requirements of ISPs. Internet service providers (ISPs) require systems that can (a) scale to handle millions of users and (b) reduce downtime to an absolute minimum. Although past versions of Exchange were not up to these challenges, Exchange 2000 employs a variety of new or improved technologies-technologies that reside in Windows 2000, WWS, and Exchange 2000-to enable customers to construct a “virtual server” composed of multiple machines that appears to the user to be a single, very large, high-availability system.

The Exchange 2000 Virtual Server

An Exchange 2000 virtual server relies heavily on Windows 2000 technologies as well as changes to the Exchange IS to achieve its scalability and availability goals. (See the illustration “Exchange 2000 Scalability and Availability“) The technologies underlying a virtual server include the following:

• Network Load Balancing (NLB) in Windows 2000
• Offload