Volt (V) A unit of electromotive force, It is the difference of potential required to make a current of one ampere through a resistance of one ohm.
Voltage The term most often used (in place of electromotive force, potential, potential difference or voltage drop) to designate electrical pressure that exists between two points and is capable of producing between the two points.
Voltage drop Voltage loss experience by electric circuit due to two principal factors: (1) wire size and (2) length of wire runs.
Volt/amp (VA) rating The product of rated input voltage multiplied by the rated current. This establishes "apparent energy" available accomplish work.
Virtual Private Network (VPN) : A restricted-use, logical (i.e., artificial or simulated) computer network that is constructed from the system resources of a relatively public, physical (i.e., real) network (such as the Internet), often by using encryption (located at hosts or gateways), and often by tunneling links of the virtual network across the real network. For example, if a corporation has LANs at several different sites, each connected to the Internet by a firewall, the corporation could create a VPN by (a) using encrypted tunnels to connect from firewall to firewall across the Internet and (b) not allowing any other traffic through the firewalls. A VPN is generally less expensive to build and operate than a dedicated real network, because the virtual network shares the cost of system resources with other users of the real network.
Virus : A hidden, self-replicating section of computer software, usually malicious logic, that propagates by infecting - i.e., inserting a copy of itself into and becoming part of - another program. A virus cannot run by itself; it requires that its host program be run to make the virus active.
Voice Firewall : A physical discontinuity in a voice network that monitors, alerts and controls inbound and outbound voice network activity based on user-defined call admission control (CAC) policies, voice application layer security threats or unauthorized service use violations.
Voice Intrusion Prevention System (IPS) : Voice IPS is a security management system for voice networks which monitors voice traffic for multiple calling patterns or attack/abuse signatures to proactively detect and prevent toll fraud, Denial of Service, telecom attacks, service abuse, and other anomalous activity.