Remote GUI logins can be a useful tool for enabling users to run complex GUI programs remotely and even for system administration. Windows benefits the most from remote GUI system administration, because text-mode Linux tools are usually sufficient. Two tools are particularly important in cross-platform remote GUI logins: X and VNC. X is Linux's native GUI tool and is a very useful way to access a Linux system from another Linux system or from a Windows system. VNC is a cross-platform tool that can enable Linux or Windows clients to access either Linux or Windows servers. (Other operating systems are also supported.) One problem with both X and VNC is that they don't encrypt data by default, with the exception of VNC passwords. One way around this limitation is to employ SSH as a tunneling protocol. This process works most easily with X, but, with a bit of effort, it can also be used with VNC.