(U) HTTPS – HTTP traffic secured inside an SSL/TLS session, indicated by the https:// URL, commonly using TCP port 443
(U) IPSEC -- IPSec, or IP Security, is the Internet Engineering Task Force (IETF) standard for layer 3 real-time communication security. IPSec allows two hosts (or two gateways) to establish a secure connection, sometimes called a tunnel. All traffic is protected at the network layer.
(U) SSH – Secure Shell. A common protocol used for secure remote computer access
(U) SSL – Secure Sockets Layer. Commonly used to provide secure network communication. Widely used on the internet to provide secure web browsing, webmail, instant messaging, electronic commerce, etc.
(U) TLS – Transport Layer Security. The follow-on to SSL, SSLv3 and TLSv1.0 are nearly identical.
(U) VoIP – Voice over Internet Protocol. A general term for the using IP networks to make voice phone calls. The application layer protocol can be standards-based (e.g., H.323, SIP), or proprietary (e.g., Skype).
(U) VPN – Virtual Private Network. A private network that makes use of the public telecommunications infrastructure, maintaining privacy via the use of a tunneling protocol and security procedures that typically include encryption. Common protocols include IPSEC and PPTP.