STUN stands for Simple Traversal of User Datagram Protocol (UDP) Through Network Address Translators (NATs). STUN operates together with several other systems that achieve NAT traversal including: TURN, ICE UpnP and Session Border controllers. The efforts these systems seek to allow relate to withdrawing the limitations a client needs to experience in order to investigate its environment, although by doing so the environment complexity is significantly increased.

The Signaling System 7 (SS7) network was designed as a management tool to automatically organize call routing by assessing at a fraction of the time it would take to achieve manually the most appropriate direction in which a call should be sent with the support of all telephony services including 800 numbers, call forwarding, caller ID and local number portability. The SS7 Protocol was adopted as a standard by ITU-T in 1981 in its ITU-T Q7XX-series.