IP address affinity is a technique used for load balancing in which requests from an individual IP address are always sent to the same web server. This ensures that users always get the same page no matter how many requests they make. This can be beneficial in certain scenarios, such as when personalization or session state information needs to be maintained between multiple sessions with the same user. By directing all traffic from an individual user to a single server, this information can be stored and easily accessed by that server on subsequent visits.   The way IP address affinity works is relatively straightforward. When a request comes in, the load balancer checks the requesting IP address against its list of known addresses and then directs the request accordingly.   If the requested IP address isn't already associated with any particular server, then the load balancer will select one randomly and assign it as that user's “affinity” server going forward, ensuring that their next visit will be sent directly to that server without further checking required. In addition, if an affinity server becomes unavailable or overwhelmed with traffic, then the load balancer can transparently reassign that user's requests to another available server without them having to do anything differently.