A persistent connection is understood to be a persistent, permanent connection. This connection type is of particular importance for the load balancing of webswitches.
With this connection type, the webswitch must use persistence to ensure that successive connections are routed to the same server of a server farm. There are various methods to ensure such a configuration, such as Secure Socket Layer( SSL) or session tracking by modifying cookies.
Persistent connections can also be established with TCP/ IP to increase data throughput. The SPDY protocol uses this technique to accelerate the calling of web pages.