U

UDP (User Datagram Protocol), 57-59, 62, 66

Unicast addressing, 81

Uniform Resource Locator (URL), 66

UNIX/LINUX, 6, 102, 160, 311, 453

Unknown network, 289

Unshielded Twisted-Pair (UTP) cabling, 199

Untrusted network, 289

User Datagram Protocol (UDP), 294

User-based security, 244, 246, 248-49