DnsMuxTM is a computer networking device manufactured by CAI Networks, Inc. Its function is to dynamically respond to DNS questions with the IP address of one of several geographically disparate web servers in a logical cluster that will provide the best performance for each user. DnsMux makes such performance decisions based on the relative loading of available web servers in the cluster and/or the geographical proximity of web servers to the user's determined geographical location.
DnsMux is able to not only target users to the appropriate web server hosting site based on geographical distance (proximity), it is also able to target users based on content-based preferences (affinity). For examples, users located in parts of the world that speak a particular language can be automatically targeted to web servers that host content in those users' language.
DnsMux provides geographically based fault tolerance/failover and load balancing by allowing any of several geographically disparate hosting sites to stand in for each other. DnsMux automatically performs a regular health-check on each web server in a cluster to determine both availability and performance characteristics. DnsMux is able to automatically make proximity-based targeting decisions, while affinity-based decisions require configuration.
DnsMux can be used in combination with CAI Networks' WebMux network appliance to provide both geographically based and LAN-based load balancing and fault tolerance.