What are VPN Tunnels?

UCI has two types of VPN tunnels, a "split" tunnel and a "full" tunnel. 

Split Tunnel
The "split" tunnel only sends traffic destined for UCI over the VPN connection.  All other traffic goes through your normal cable modem/dsl connection.  

Use the "split" tunnel for connections to and from UCI only. If you are using online Library resources, use the "full" tunnel.

It allows you to talk directly to the Internet, but when your machine "talks" to UCI network addresses the traffic is put through the established VPN tunnel to the UCI VPN node, where it is decrypted and given a UCInet network address.

This is useful for people who need access to things at UCI which require a UCInet IP address (such as connecting to a system that restricts access to UCI hosts only), or to use services which are blocked for security reasons at the campus firewall (such as NetBIOS ports, used in mounting shared drives and other ports used by Microsoft Windows). Only traffic to/from UCI is sent through the VPN connection, so if you were to access Yahoo, it would go through your regular network connection (cable modem, dsl, etc).

Full Tunnel
The "full" tunnel sends all your internet traffic through the VPN connection, and then out to the internet through UCI's connection.

The "full" tunnel is useful for people who need to access sites off-campus that need a UCI IP address to allow access to a resource. The UCI Library has links to resources such as these. If you wanted to access the Oxford English Dictionary (OED), you can't get to it with a split tunnel because it's off campus and your off-campus packets aren't network address translated to UCI addresses. By using the "full" tunnel, this problem is circumvented. However, note that *all* your traffic is sent through the VPN connection and then out UCI's internet connection.

You should use the "full" tunnel VPN connection with care since heavy use can cause an increase in UCI's internet connection costs, and is likely slower than the split tunnel method.