threat Anything you are trying to protect against.
top-level domain (TLD) name server A DNS server
that hosts the last portion of the hostname (such as .com,
.org, or .net).
Transmission Control Protocol (TCP) A
connection-oriented transport layer protocol.
Transmission Control Protocol/Internet
Protocol (TCP/IP) A network reference model based
on a layered approach.
Transport Layer Security (TLS) A widely adopted
security protocol designed to facilitate privacy and data
security for communications over the Internet.
U
Unified Communications Cisco equipment, software,
and services that combine multiple enterprise
communications channels, such as voice, video,
messaging, voicemail, and content sharing.
Unified Computing System (UCS) A Cisco compute
product.
unit test A type of test that is meant to ensure that
individual pieces of code are operating as they are
supposed to. A unit is the smallest testable part of any
software.
User Datagram Protocol (UDP) A connectionless
transport layer protocol.
V
variable-length subnet masking (VLSM) A way to
indicate how many bits in an IP address are dedicated to
the network ID and how many bits are dedicated to the
host ID.
Virtual Internet Routing Laboratory (VIRL) A
powerful Cisco network simulation platform that is
meant to be a flexible, all-in-one virtual networking lab.