All web-based resources are routed through the proxy, with minor exceptions. For example, SciFinder, a specialized chemical research database for which users must create an account for access, is not authenticated through the proxy.
The proxy requires no action on the user's part, except to start your search from the library's website and to log in using your NetID and password. It requires no special software, accounts or updating on the user's machine.
A VPN no longer offers any enhanced benefit for accessing library resources. However, it may help troubleshoot access issues when using library databases off campus.