UDP

ALSO CALLED: Internet Key Exchange, User Datagram Protocol, UDP Port 500, UDP 500, UDP/500, IKE (Internet Key Exchange), Datagram Protocol
DEFINITION: Simple Traversal of UDP through NAT (STUN) is a protocol that governs the exchange of data over a User Datagram Protocol (UDP) connection by communications devices operating behind a Network Address Translator (NAT) or firewall. The main objective of STUN is to overcome some of the problems associated with the lack of standardized behaviors in NATs. STUN works with a variety of NATs and application  … 
Definition continues below.

UDP DEFINITION (continued): …  programs. However, STUN does not allow incoming UDP packets through symmetric NATs and cannot be used to obtain an Internet Protocol address (IP address) to communicate with a peer behind the same NAT.A NAT translates an IP address used within a network to a different IP address within another network. This enhances security because each outgoing or incoming request must go through a translation process that offers the opportunity for authentication. The use of a NAT can also minimize the number of global IP addresses that an enterprise requires. A firewall is a set of programs, located at a gateway … 
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