V

value

A configuration setting that corresponds to a key used in an answer file.

virtual DOS machine (NTVDM)

A special application environment that a newer operating system creates to simulate the environment that a DOS application expects.

virtual local area networks (VLANs)

Logical subnets that are formed using switches and provide flexibility in network design and management.

virtual private network (VPN)

A connection to an existing network from a remote location through private or public IP networks using encapsulated packets that are encrypted and difficult to decrypt by unauthorized users. These are often used to improve security and avoid long-distance charges.

virus

A piece of self-replicating code attached to some other piece of code. This code can be harmless or harmful, depending on what the developer wrote the code to do. The virus code searches users' files for an uninfected executable program for which the user has security write privileges. The virus infects the file by putting a piece of code in the selected program file. When a program infected with a virus is executed, the virus immediately takes command, finding and infecting other programs and files.

VLAN membership

The assignment of port to a specific VLAN when using port-based VLANs.

volume

An area of space on one disk or multiple disks that can be used to store data. Volumes can contain multiple partitions.