Address Resolution Protocol (ARP)

An Internet protocol for resolving an IP address into a physical layer address (such as an Ethernet media access control address). See also Physical Layer, Internet Protocol.

Advanced Research Projects Agency Network (ARPANET)

Predecessor to the Internet that was developed by the Department of Defense in the late 1960s.

AppleTalk

The built-in (to firmware) suite of network protocols that Macintosh computers use. Windows NT Server uses AppleTalk to service Macintosh clients by simulating an Apple server. Sec also Macintosh, Network Protocol.

Administrators

Users who are part of the Administrators group. This group has the ultimate set of security permissions. See also Administrator Account, Permissions, Groups.

Encryption

The process of obscuring information by modifying it according to a mathematical function known only to the intended recipient. Encryption secures information being transmitted over non- secure or untrusted media. See also Security.

Home Directory

A directory that stores a user's personal files.

Directories

 In a file system, directories are containers that store files or other directories. Mass storage devices have a root directory that contains all other directories, thus creating a hierarchy of directories sometimes referred to as a directory tree. See also File, File System.

Bridge

A device that connects two networks of the same data link protocol by forwarding those packets destined for computers on the other side of the bridge. See also Router, Data Link Layer.

Bridge

A device that connects two networks of the same data link protocol by forwarding those packets destined for computers on the other side of the bridge. See also Router, Data Link Layer.

Compression

A space-optimization scheme that reduces the size (length) of a data set by exploiting the fact that most useful data contains a great deal of redundancy. Compression reduces redundancy by creating symbols smaller than the data they represent and an index that defines the value of the symbols for each compressed set of data.

Components

Interchangeable elements of a complex software or hardware system. See also Module.

Hardware Profile,

Used to manage portable computers that have different configurations based on their location.

Dynamic Host Configuration Protocol (DHCP)

A method of automatically assigning IP addresses to client computers on a network.

Groups

Security entities to which users can be assigned membership for the purpose of applying the broad set of group permissions to the user. By managing permissions for groups and assigning users to groups, rather than assigning permissions to users, security administrators con keep coherent control of very large security environments. See also Permissions, Accounts, Security Local Group, Global Group.

Disk Administrator

Graphical utility used to manage disks.

Bottlenecks

Components operating at their peak capacity that restrict the flow of information through a system. Used singularly, the term indicates the single most restrictive component in a system.

Hypertext Transfer Protocol (HTTP)

Hypertext transfer protocol is an Internet protocol that transfers HTML documents over the Internet and responds to context changes that happen when a user clicks a hypertext link. See also Hypertext Markup Language, World Wide Web

Fiber Distributed Data Interface (FDDI)

A data link layer that implements two counter- rotating token rings at 100 megabits per second. FDDI has been a popular standard for interconnecting campus and metropolitan area networks because it allows distant digital connections at high speed, but ATM is replacing FDDI in many sites. See also Asynchronous Transfer Mode, Data Link Layer.

Emergency Repair Disk

A floppy diskette created by the RDISK. EXE program that contains crit- ical Registry information about a Windows NT installation. With an emergency repair disk, a Windows NT installation can be salvaged using the restore option when re-installing from CD-ROM. See also Registry.

Control Panel

A software utility that controls the function of specific operating system services by allowing users to change default settings for the service to match their preferences. The Registry contains the Control Panel settings on a system and/or per user basis.

Firmware

Software stored permanently in nonvolatile memory and built into a computer to provide its BIOS and a bootstrap routine. Simple computers may have their entire operating system built into firmware. See also BIOS, Boot, Software.

Firmware

Software stored permanently in nonvolatile memory and built into a computer to provide its BIOS and a bootstrap routine. Simple computers may have their entire operating system built into firmware. See also BIOS, Boot, Software.

Accounts

Containers for security identifiers, passwords, permissions, group associations, and prefer- ences for each user of a system. The User Manager for Domains utility is used to administer accounts. Sec also Security identifier. Preferences, Permissions, Passwords, Groups.

Domain

In Microsoft networks a domain is an arrangement of client and server computers referenced by a specific name that share a single security permissions database. On the Internet a domain is a named collection of hosts and sub-domains, registered with a unique name by the InterNIC. See also Work- group, InterNlC.

Fax Modems

Special modems that include hardware to allow the transmission and reception of fac- similes. See also Modem, Exchange.

Browsing

The process of requesting the list of computers and services on a network from a browser.

High Performance File System (HPFS)

The file system native to OS/2 that performs many of the same functions of NTFS when run under OS/2. Sec also File System. New Technology File System.

Hardware Compatibility List (HCL)

The listing of all hardware devices supported by Windows NT. Hardware on the HCL has been tested and verified as being compatible with NT.

Computer Name

 A 1- to 15-character NetBIOS name used to uniquely identify a computer on the network. See also Network Basic Input/Output System.

Exchange

Microsoft's messaging application. Exchange implements Microsoft's mail application programming interface (MAPI) as well as other messaging protocols such as POP, SNMP, and faxing to provide a flexible message composition and reception service. See also Electronic Mail, Fax Modem.

Icon

A graphical representation of a resource in a graphical user interface that usually takes the form of a small (32 x 32) bitmap. See also Graphical User Interface.

Computer

A device capable of performing automatic calculations based upon lists of instructions called programs. The computer feeds the results of these calculations (output) to peripheral devices that can represent them in useful ways, such as graphics on a screen or ink on paper. See also Microprocessor.

IDE

A simple mass storage device interconnection bus that operates at 5Mbps and can handle no more than two attached devices. IDE devices are similar to but less expensive than SCSI devices. See also Small Computer Systems Interface, Mass Storage Device.

Driver

A program that provides a software interface to a hardware device. Drivers arc written for the specific device they control, but they present a common software interface to the computer's operating system, allowing all devices (of a similar type) to be controlled as if they were the same. See also Data Link Layer, Operating System.

Hyperlink

A link in text or graphics files that have a Web address embedded within them. By clicking the link, you jump to another Web address. You can identify a hyperlink because it is a different color than the rest of the Web page. See also World Wide Web.

Administrative Tools

 Program group on Windows NT servers that contain utilities such as User Manager for Domains, Server Manager, Disk Administrator, Performance Monitor, and Network Mon- itor. See also I'ser Manager for Domains, Server Manager, Disk Administrator, Performance Monitor, Network Monitor.

Binding

The process of linking network services to network service providers-. The binding facility allows users to define exactly how network services operate in order to optimize the performance of the system. By default, Windows enables all possible bindings. You can use the Network control panel to change bindings.

File Transfer Protocol (FTP)

A simple Internet protocol that transfers complete files from an FTP server to a client running the FTP client. FTP provides a simple method of transferring files between computers, but cannot perform browsing functions. You must know the URL. of the FTP server to which you wish to attach. See also Internet, Uniform Resource Locator.

Gateway Services for NetWare (GSNW)

An NT Server service that connects NT Servers and NT clients to NetWare resources via the gateway software. See also Gateway, NetWare, Client Services for NetWare.

COM Port Communications port.

A serial hardware interface conforming to the RS-232 standard for low-speed serial communications. See also Modem, Serial.

Access Tokens

Objects containing the security identifier of a running process. A process started by another process inherits the starting process's access token. The access token is checked against each object's ACL to determine whether or not appropriate permissions are granted to perform any requested service. See also Access Control List, Access Control Entries, Permissions. Object, Security Identifier, Process.

Address Resolution Protocol (ARP)

 An Internet protocol for resolving an IP address into a physical layer address (such as an Ethernet media access control address). See also Physical Layer, Internet Protocol.

Database

A related set of data organized by type and purpose. The term also can include the application software that manipulates the data. The Windows NT Registry (a database itself) contains a number of utility databases such as user account and security information.

Domain Controllers

Domain Controllers
Servers that authenticate workstation network logon requests by comparing a username and password against account information stored in the user accounts database. A user cannot access a domain without authentication from a domain controller. See also Primary Domain Controller, Backup Domain Controller, Domain.

File Attributes

File Attributes
Bits that show the status of a file (e.g.. archived, hidden, read-only) are stored atone with the name and location of a file in a directory entry. Different operating systems use different tile attributes to implement such services as sharing, compression, ami security.

Browser

Browser
A computer on a Microsoft network that maintains a list of computers and services available on the network.

Account Lockout

Account Lockout
Used to specify how many invalid logon attempts should be tolerated before a user account is locked out. Account lockout is set through User Manager for Domains.

Write-Back Caching

 A caching optimization wherein data written to the slow store is cached until the cache is full or until a subsequent write operation overwrites the cached data. Write-back caching can significantly reduce the write operations to a slow store because many write operations are subsequently obviated by new information. Data in the write-back cache is also available for subsequent reads. If something happens to prevent the cache from writing data to the slow store, the cache data will be lost.

Windows Internet Name Service (WINS)

 A network service for Microsoft networks that provides Windows computers with Internet numbers for specified NetBIOS names, facilitating browsing and intercommunication over TCP/IP networks.

Ethernet

The most popular data link layer standard for local area networking. Ethernet implements the carrier sense multiple access with collision detection (CSMA/CD) method of arbitrating multiple computer access to the same network. This standard supports the use of Ethernet over any type of media including wireless broadcast. Standard Ethernet operates as 10 megabits per second. Fast Ethernet operates at 100 megabits per second

Swap File

The virtual memory file on a hard disk containing the memory pages that have been moved out to disk to increase available RAM

Universal Naming Convention.(UNC)

 A multivendor, multiplatform convention for identifying shared resources on a network.

Access Control Entries

Access Control Entries
ACLs for objects contain access control entries, each of which describes a specific permission for a specific service for a user or a group

Access Control Lists

Access Control Lists

Each object has an ACL attribute that describes which user or group accounts have access to the object and what type of access they have. If a user does not have an entry in the ACL allowing access to a service of an
object, Windows NT will