Potential customers shopping for products or researching a company will move on to another site to get what they are looking for if they are faced with sub-par performance or missing content. Any down time or less than optimal response to customers or potential customers has a negative impact on the bottom line. Clearly, businesses that want to maximize their return on investments made to capture Internet traffic and properly service Intranet users must design their sites to provide both scalability and high availability. In this paper, we'll discuss the distinction between load balancing and high availability and introduce the notion of quality of service based availability. In order to provide guaranteed availability, a solution must provide both high availability and load balancing.
Load balancing is a crucial component of building scalable systems.
High availability guarantees that end users always receive the quality of service desired. Without first determining availability, load balancing alone is of limited value. The first solutions that have come to market to address these issues don't solve both problems completely. Most solutions provide rudimentary load balancing in order to address the issue of scalability and provide some degree of increased availability. However, they are not capable of performing thorough availability analysis before deciding where to send traffic which results in poor customer service.