In the Application Usage and Risk Report, encrypted tunnel applications such as SSL and SSH were found in 100% and 89% of the organizations, respectively. Other examples such as TOR and Gbridge were also found, although not nearly as often. The common thread is that they all let users bask in the warmth of an encrypted tunnel, safe in the knowledge that their activity is hidden. These applications, along with external proxies are perfect examples of the extremes that are being used in the enterprise networks.
Source: https://threatpost.com/encrypted-tunnels-enable-users-circumvent-security-controls-060109/72742/