EZProxy is a proxy server used for accessing library recourses online. A proxy server is a server that acts as a middleman to serve between a client and another server - in this case online Library resources.
CUNE library resources are available while on the campus network, so for students to access resources off-campus, they authenticate to this on-campus proxy server, which accesses library resources for them.
This server is accessed automatically when trying to access library resources off-campus; students or employees simply sign in with their CUNE username and password and continue with their research. EZProxy is bypassed when connecting to said resources while on the campus network, as you can connect to those services directly.