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<p style="color:red">[This is preliminary documentation and subject to change]</p>
<h1>Glossary</h1><a name="glossary"></a><h3><span><a href="#GlossaryA"><b>A</b></a><a href="#GlossaryB"><b>B</b></a><a href="#GlossaryC"><b>C</b></a><a href="#GlossaryD"><b>D</b></a><a href="#GlossaryE"><b>E</b></a><a href="#GlossaryF"><b>F</b></a><a href="#GlossaryG"><b>G</b></a><a href="#GlossaryH"><b>H</b></a><a href="#GlossaryI"><b>I</b></a><a href="#GlossaryJ"><b>J</b></a><a href="#GlossaryK"><b>K</b></a><a href="#GlossaryL"><b>L</b></a><a href="#GlossaryM"><b>M</b></a><a href="#GlossaryN"><b>N</b></a><a href="#GlossaryO"><b>O</b></a><a href="#GlossaryP"><b>P</b></a><a href="#GlossaryQ"><b>Q</b></a><a href="#GlossaryR"><b>R</b></a><a href="#GlossaryS"><b>S</b></a><a href="#GlossaryT"><b>T</b></a><a href="#GlossaryU"><b>U</b></a><a href="#GlossaryV"><b>V</b></a><a href="#GlossaryW"><b>W</b></a><a href="#GlossaryX"><b>X</b></a></span></h3><p>Select the first letter of the word from the list above to jump
to appropriate section of the glossary.</p><h1><a name="H1_37709226"></a><a href="#glossary"><b><img src="art/up.gif" alt="To Top"></b></a><a name="GlossaryA"><b>A</b></a></h1><b>access control</b><br>
The mechanisms for limiting access to resources based on users'
identities and their membership in various predefined groups.
Access control is used typically to control user access to network
resources such as servers, directories, and files.
<p><b>access control list (ACL)</b><br>
A list that indicates which users or groups have permission to
access or modify a particular file; the Windows discretionary
access control list (DACL) and system access control list (SACL)
are examples of access control lists.</p><p><b>ACL</b><br><i>See</i><b>access control list</b>.</p><p><b>Active Directory Service Interfaces (ADSI)</b><br>
A COM-based directory service model that allows ADSI-compliant
client applications to access a wide variety of distinct directory
protocols, including Windows Directory Services and Lightweight
Directory Access Protocol (LDAP), while using a single, standard
set of interfaces. ADSI shields the client application from the
implementation and operational details of the underlying data store
or protocol.</p><p><b>Active Group, The</b><br>
A standards organization, under the auspices of The Open Group,
which is an open, customer-driven steering committee responsible
for the ongoing development and management of ActiveX technologies
and licensing.</p><p><b>active script</b><br>
A script that can be implemented in various languages, persistent
formats, and so on, that can interact with other ActiveX
Controls.</p><p><b>active scripting</b><br>
A Microsoft technology that uses COM to run third-party scripts in
Microsoft Internet Explorer without regard to language and other
elements of implementation. See also <b>Active Server Pages</b>;
<b>Automation</b>; <b>Component Object Model component</b>; <b>
script</b>; <b>scripting engine</b>.</p><p><b>Active Server Pages (ASP)</b><br>
A server-side scripting environment that can be used to create
dynamic Web pages or build Web applications. ASP pages are files
that contain HTML tags, text, and script commands. ASP pages can
call Component Object Model (COM) components to perform tasks, such
as connecting to a database or performing a business calculation.
With ASP, the user can add interactive content to Web pages or
build entire Web applications that use HTML pages as the interface
to your customers.</p><p><b>ActiveX</b><br>
An umbrella term for Microsoft technologies that enable developers
to create interactive content for the World Wide Web. A set of
language-independent interoperability technologies that enable
software components written in different languages to work together
in networked environments. The core technology elements of ActiveX
are the Component Object Model (COM) and distributed COM. These
technologies are licensed to The Open Group standards organization,
and are being implemented on multiple platforms. See also <b>
Reusable software components that incorporate ActiveX technology.
These components can be used to add specialized functionality, such
as animation or pop-up menus, to Web pages, desktop applications,
and software development tools. ActiveX Controls can be written in
a variety of programming languages including C, C++, Visual Basic,
and Java.</p><p><b>ActiveX Data Objects (ADO)</b><br>
A high-level data access programming interface to an underlying
data access technology (such as OLE DB), implemented by using the
Component Object Model (COM).</p><p><b>activity</b><br>
A collection of COM objects that has a single distributed logical
thread of execution. Every COM object belongs to one activity.</p><p><b>Address Resolution Protocol (ARP)</b><br>
A TCP/IP protocol for determining the hardware address (or
physical address) of a node on a local area network connected to
the Internet, when only the IP address (or logical address) is
known. An ARP request is sent to the network, and the node that has
the IP address responds with its hardware address. Although ARP
technically refers only to finding the hardware address, and
Reverse ARP (RARP) refers to the reverse procedure, the acronym ARP
is commonly used to describe both. ARP is limited to physical
network systems that support broadcast packets. It is defined in
RFC 826. See also <b>Reverse Address Resolution Protocol</b>; <b>
Transmission Control Protocol/Internet Protocol</b>.</p><p><b>ADO</b><br><i>See</i><b>ActiveX Data Objects</b>.</p><p><b>ADSI</b><br><i>See</i><b>Active Directory Service Interfaces</b>.</p><p><b>ADSI Provider</b><br>
An application that makes itself available to ADSI client
applications by providing an ADSI implementation.</p><p><b>agent</b><br>
In client/server applications, a process that mediates between the
client and the server. In Simple Network Management Protocol
(SNMP), agent information consists of comments about the user, the
physical location of the computer, and the types of service to
report based on the computer's configuration. See also <b>catalog
agent</b>.</p><p><b>aggregation</b><br>
A composition technique for implementing component objects whereby
a new object can be built by using one or more existing objects
that support some or all of the new object's required
interfaces.</p><p><b>alias</b><br>
A name that maps part of a URL to a physical directory on the
server. In general, an easily remembered name used in place of an
IP address, directory path, or other identifier; also called a
friendly name. See also <b>host name</b>; <b>virtual directory</b>;
<b>virtual server</b>.</p><p><b>American National Standards Institute (ANSI)</b><br>
A voluntary, nonprofit organization of U.S. business and industry
groups formed in 1918 for the development of trade and
communication standards. It provides area charters for groups that
establish standards in specific fields, such as the Institute of
Electrical and Electronics Engineers (IEEE). ANSI is the American
representative of the International Standards Organization and has
developed recommendations for the use of programming languages
including FORTRAN, C, and COBOL. Standards approved by ANSI are
often called ANSI standards (for example, ANSI C is the version of
the C language approved by ANSI). See also <b>ASCII</b>; <b>ASCII
character set</b>; <b>ASCII file</b>.</p><p><b>American Standard Code for Information Interchange
(ASCII)</b><br>
A coding scheme using 7 or 8 bits that assigns numeric values up
to 256 characters, including letters, numerals, punctuation marks,
control characters, and other symbols. ASCII was developed in 1968
to standardize data transmission among disparate hardware and
software systems and is built into most minicomputers and all
personal computers.</p><p><b>annotation file</b><br>
For the FTP service, a summary of the information in a given
directory. This summary appears automatically to browsers.</p><p><b>Anonymous File Transfer Protocol (anonymous FTP)</b><br>
Makes it possible for a user to retrieve documents, files,
programs, and other archived data from anywhere on the Internet
without having to establish a logon name and password.</p><p><b>anonymous-only logons</b><br>
Allows remote access by the IUSR_<i>computername</i> account.
Remote users can connect to that computer without a user name or
password, and they have only the permissions assigned to that
account. Anonymous access is typically used for Internet sites.</p><p><b>ANSI</b><br><i>See</i><b>American National Standards Institute</b>.</p><p><b>Apartment model multithreading</b><br>
The Component Object Model (COM) supports a form of multithreading
called the Apartment model. The apartment is essentially a way of
describing a thread with a message queue that supports COM objects.
Apartment model multithreading enables multiple application
threads-one for each apartment-to be managed by COM.</p><p><b>Apartment thread</b><br>
A thread used to execute calls to objects of components configured
as "Apartment threaded." Each object "lives in an apartment"
(thread) for the life of the object. All calls to that object
execute on the Apartment thread.</p><p><b>API</b><br><i>See</i><b>application programming interface</b>.</p><p><b>applet</b><br>
A small piece of code that can be transported over the Internet
and executed on a client's computer. This term is frequently used
to refer to such programs in the form of embedded inline objects in
HTML documents on the World Wide Web.</p><p><b>application</b><br>
A computer program, such as a word processor or electronic
spreadsheet; or a group of Active Server Pages (ASP) scripts and
components that perform such tasks.</p><p><b>application programming interface (API)</b><br>
A set of routines that an application uses to request and carry
out lower-level services performed by a computer's operating
system. Also, a set of calling conventions in programming that
define how a service is invoked through the application.</p><p><b>application root</b><br>
The root directory for an application; all directories and files
contained within the application root are considered part of the
application. Also called an application starting-point
directory.</p><p><b>application scope</b><br>
A way of making data available to all users of an application from
all pages of a Web application. A variable or an object instance is
given application scope by storing it in the Active Server Pages
(ASP) application object. Application scope is useful for global
data, such as a global counter.</p><p><b>argument</b><br>
A constant, variable, or expression passed to a procedure.</p><p><b>ARP</b><br><i>See</i><b>Address Resolution Protocol</b>.</p><p><b>array</b><br>
A list of data values, all of the same type, any element of which
can be referenced by an expression consisting of the array name
followed by an indexing expression. Arrays are part of the
fundamentals of data structures, which, in turn, are a major
fundamental of computer programming.</p><p><b>ascii</b><br>
In an FTP client program, the command that instructs the FTP server
to send or receive files as ASCII text. See also <b>ASCII</b>.</p><p><b>ASCII</b><br><i>See</i><b>American Standard Code for Information
Interchange</b>.</p><p><b>ASCII character set</b><br>
A standard 7-bit code for representing ASCII characters by using
binary values; code values range from 0 to 127. Most PC-based
systems use an 8-bit extended ASCII code, with an extra 128
characters used to represent special symbols, non-English language
characters, and graphic symbols.</p><p><b>ASCII file</b><br>
Also called a text file, a text-only file, or an ASCII text file.
An ASCII file contains characters, spaces, punctuation, carriage
returns, and sometimes tabs and an end-of-file marker, but it
contains no other formatting information.</p><p><b>ASP</b><br><i>See</i><b>Active Server Pages</b>.</p><p><b>ASP buffering</b><br>
Functionality of ASP that temporarily stores all output generated
by a script until script execution is complete, then sends it to a
client.</p><p><b>associating</b><br><i>See</i><b>file name extension mapping</b>.</p><p><b>asynchronous transfer mode (ATM)</b><br>
A network technology capable of transmitting data, voice, video,
and frame relay traffic in real time. Data, including frame relay
data, is broken into packets containing 53 bytes each, which are
switched between any two nodes in the system at rates ranging from
1.5 to 622 Mbps. ATM is defined in the broadband ISDN protocol at
the levels corresponding to levels 1 and 2 of the ISO/OSI model. It
is currently used in local area networks involving workstations and
personal computers. See also <b>Integrated Services Digital
Network</b>; <b>International Organization for Standardization Open
Systems Interconnection model</b>.<br></p><p><b>asynchronous transmission</b><br>
In modem communication, a form of data transmission in which data
is sent intermittently, one character at a time, rather than in a
steady stream with characters separated by fixed time intervals.
Each transmitted character consists of a number of data bits (the
character itself) preceded by a "begin character" signal called the
start bit, and ending in an optional parity bit followed by 1, 1.5,
or 2 "end character" signals, called stop bits.</p><p><b>ATM</b><br><i>See</i><b>Asynchronous Transfer Mode</b>.</p><p><b>atomicity</b><br>
A feature of a transaction considered or guaranteed to be
indivisible. Either the transaction is uninterrupted, or, if it
fails, a mechanism is provided that ensures the return of the
system to its state prior to initiation of the transaction.</p><p><b>attributes</b><br>
In a database record, the name or structure of a field. The size
of a field or the type of information it contains would also be
attributes of a database record. In markup languages such as
Standard Generalized Markup Language (SGML) and HTML, a name-value
pair within a tagged element that modifies certain features of that
element.</p><p><b>auditing</b><br>
The process an operating system uses to detect and record
security-related events, such as an attempt to create, access, or
delete objects such as files and directories. The records of such
events are stored in a file known as a security log, whose contents
are available only to those with the proper clearance. See also <b>
security log</b>.</p><p><b>authentication</b><br>
The process by which the system validates a user's logon
information. A user's name and password are compared against an
authorized list, and if the system detects a match, access is
granted to the extent specified in the permission list for the
A codepage is used by the system to encode and interpret string
characters. Codepage formats are not the same for each language.
Some languages such as Japanese and Hindi have multi-byte
characters while others like English and German only need one byte
to represent each character. Each codepage is represented by a
unique integer. In IIS, the default codepage is the same as CP_ACP.
IIS supports Web files saved in UTF-8 format or ANSI format. See
also <b>CP_ACP</b><b>, UTF-8</b>.</p><p><b>colocation</b><br>
Installing and maintaining a computer at an Internet Service
Provider (ISP) that belongs to another company or group. For
example, a company might colocate one of their servers at an ISP to
save costs, or to make large-scale upgrades easier.</p><p><b>COM</b><br><i>See</i><b>Component Object Model</b>.</p><p><b>commit</b><br>
The phase in a transaction when all interactions are finalized and
the persistent state of the underlying database is changed.</p><p><b>Common Gateway Interface (CGI)</b><br>
A server-side interface for initiating software services. The
specification that defines communications between information
services (such as an HTTP service) and resources on the server's
host computer, such as databases and other programs. For example,
when a user submits a form through a Web browser, the HTTP service
executes a program (often called a CGI script) and passes the
user's input information to that program through CGI. The program
then returns information to the service through CGI. Any software
can be a CGI program if it handles input and output according to
the CGI standard. CGI applications always run out-of-process. See
also <b>server</b>.</p><p><b>Common Gateway Interface (CGI) bin directory</b><br>
The directory on a server where CGI script programs are stored.
Commonly called CGI-bin or CGI-scripts.</p><p><b>Common Gateway Interface (CGI) script</b><br>
A program that allows a server to communicate with users on the
Internet. For example, when a user enters information in a form on
a Web page, a CGI script interprets the information and
communicates it to a database program on the server.</p><p><b>Common Object Request Broker Architecture (CORBA)</b><br>
A specification developed by the Object Management Group in 1992
in which pieces of programs (objects) communicate with other
objects in other programs, even if the two programs are written in
different programming languages and are running on different
platforms. A program makes its request for objects through an
object request broker, or ORB, and thus does not need to know the
structure of the program from where the object comes. CORBA is
designed to work in object-oriented environments.</p><p><b>communications protocol</b><br>
A set of rules or standards designed to enable computers to
connect with one another and to exchange information with as few
errors as possible. Some communications protocols contain other
protocols, such as hardware protocols and file transfer protocols.
Examples include Hypertext Transfer Protocol, Transmission Control
Protocol/Internet Protocol (TCP/IP), and Systems Network
Architecture (SNA).</p><p><b>compile time</b><br>
The time during which a program is translated from source language
into machine language.</p><p><b>Component Object Model</b><br>
The object-oriented programming model that defines how objects
interact within a single application or between applications. In
COM, client software accesses an object through a pointer to an
interface-a related set of functions called methods-on the
object.</p><p><b>Component Object Model (COM) component</b><br>
A binary file containing code for one or more class factories, COM
classes, registry-entry mechanisms, loading code, and so on. See
also <b>Component Object Model</b>; <b>distributed Component Object
Model</b>.</p><p><b>concurrency</b><br>
The appearance of simultaneous execution of processes or
transactions by interleaving the execution of multiple pieces of
work.</p><p><b>connected user</b><br>
A user who is currently accessing one of the services of a Web
server.</p><p><b>connection pooling</b><br>
A performance optimization based on using collections of
pre-allocated resources, such as objects or database connections.
Pooling results in more efficient resource allocation.</p><p><b>content type</b><br>
The type of file (such as text, graphic, or sound), usually
indicated by the file name extension (such as .txt, .gif, or .wav,
respectively).</p><p><b>control</b><br>
In a graphical user interface (GUI), an object on the screen that
can be manipulated by a user to perform an action. Perhaps the most
common controls are buttons that a user can click to select an
option, and scroll bars that a user employs to move through a
document or position text in a window.</p><p><b>cookies</b><br>
A means by which, under the HTTP protocol, a server or a script
can maintain information on the client computer. Cookies are small
text files which are stored in the user's browser by the Web
server. Cookies contain information about the user such as an
identification number, a password, how a user shopped on a Web
site, or how many times the user visited that site. A Web site can
access cookie information whenever the user connects to the
server.</p><p><b>CORBA</b><br><i>See</i><b>Common Object Request Broker Architecture</b>.</p><p><b>counters</b><br><i>See</i><b>Counters Component</b> (a simple COM object ships
with IIS) or <b>Performance Counters</b> (used to measure system
performance).</p><p><b>Counters Component</b><br>
An installable component of IIS that allows you to create, store,
increment, or retrieve any number of individual custom counters.
Not to be confused with the Performance Counters installed with
Windows to monitor system performance.</p><p><b>CP_ACP</b><br>
The system ANSI CodePage. There is also a system OEM CodePage,
CP_OEMCP. See also <b>codepage</b>.</p><p><b>crawler</b><br><i>See</i><b>spider</b>.</p><p><b>CryptoAPI</b><br><i>See</i><b>Microsoft Cryptographic API</b>.</p><p><b>Cryptographic Service Providerá</b><br>
The Microsoft CryptoAPI provides a set of functions that allow
applications to encrypt or digitally sign data in a flexible manner
using certificates. Cryptographic operations (encryption) are
performed by independent modules known as cryptographic service
providers (CSPs). When you create a certificate for your server,
you can select a Microsoft CSP or a third-party CSP if you have one
A field science involving the transmission of information in an
encoded form so that only an intended recipient can decode the
information and reveal its meaning. Encoded information is commonly
said to be encrypted.</p><p><b>CSP</b><br><i>See</i><b>Cryptographic Service Provider</b>.</p><p><b>cursor</b><br>
An onscreen indicator, such as a blinking underline or rectangle,
that marks the place at which a keystroke will appear when typed.
In applications and operating systems that use a mouse, the arrow
or other onscreen icon that moves with movements of the mouse.
Also, a piece of software that returns rows of data to the
application. A cursor on a resultset indicates the current position
in the resultset.</p><p><b>cycle</b><br>
In logging, to close an existing log file and start a new one.</p><h1><a name="H1_37715975"></a><a href="#glossary"><b><img src="art/up.gif" alt="To Top"></b></a><a name="GlossaryD"><b>D</b></a></h1><b>daemon</b><br>
A networking program that performs a housekeeping or maintenance
utility function without being called by the user. A daemon sits in
the background and is activated only when needed, for example, to
correct an error from which another program cannot recover.
<p><b>Data Encryption Standard (DES)</b><br>
A specification for encryption of computer data developed by IBM
and adopted by the U.S. government as a standard in 1976. DES uses
a 56-bit key to protect against password discovery and
playback.</p><p><b>datagram</b><br>
A self-contained, independent entity of data carrying sufficient
information to be routed from the source to the destination
computer without reliance on earlier exchanges between the source
and destination computer and the transporting network. See also <b>
A way of finding other servers on the network.</p><p><b>Web Distributed Authoring and Versioning (WebDAV)</b><br>
An extension to the HTTP 1.1 standard that facilitates access to
files and directories through an HTTP connection. Remote authors
can add, search, delete, or change directories and documents and
their properties.</p><p><b>distributed COM</b><br>
A wire protocol that enables software components to communicate
directly over a network.</p><p><b>Distributed interNet Application Architecture (DNA)</b><br>
Microsoft's architecture for Web applications.</p><p><b>distributed processing</b><br>
A form of information processing in which work is performed by
separate computers linked through a communications network.
Distributed processing is usually categorized as either plain
distributed processing or true distributed processing. Plain
distributed processing shares the workload among computers that can
communicate with one another. True distributed processing has
separate computers perform different tasks in such a way that their
combined work can contribute to a larger goal. The latter type of
processing requires a highly structured environment that allows
hardware and software to communicate, share resources, and exchange
information freely.</p><p><b>DLL</b><br><i>See</i><b>dynamic-link library</b>.</p><p><b>DNS</b><br><i>See</i><b>Domain Name System</b>.</p><p><b>domain</b><br>
In Windows, a collection of computers that share a common domain
database and security policy. Each domain has a unique name. See
also <b>domain, Internet</b>.</p><p><b>domain controller</b><br>
For a Windows Server domain, the server that authenticates domain
logons and maintains the security policy and the master database
for a domain.</p><p><b>domain, Internet</b><br>
The highest subdivision of a domain name in a network address,
which identifies the type of entity owning the address (for
example, .com for commercial users or .edu for educational
institutions) or the geographical location of the address (for
example, .fr for France or .sg for Singapore). The domain is the
last part of the address (for example, www.microsoft.com).</p><p><b>domain name</b><br>
An address of a network connection that identifies the owner of
that address in a hierarchical format. For example,
www.whitehouse.gov identifies the Web server at the White House,
which is a government agency. See also <b>Domain Name
System</b>.</p><p><b>Domain Name System (DNS)</b><br>
The system by which hosts on the Internet have domain name
addresses (such as microsoft.com) and IP addresses (such as
172.21.13.45). The domain name address is used by human users and
is automatically translated into the numerical IP address, which is
used by the packet-routing software. DNS is also the acronym for
Domain Name Service, the Internet utility that implements the
Domain Name System. DNS servers, also called name servers, maintain
databases containing the addresses and are accessed transparently
by the user.</p><p><b>Domain Name System (DNS) reverse lookup</b><br>
Finding the IP address that corresponds to a domain name.</p><p><b>Domain Name System (DNS) spoofing</b><br>
Assuming the DNS name of another system by either corrupting a
name-service cache, or by compromising a domain-name server for a
valid domain.</p><p><b>download</b><br>
In communications, the process of transferring a copy of a file
from a remote computer to the requesting computer by means of a
modem or network.</p><p><b>DSN</b><br><i>See</i><b>Data Source Name</b>.</p><p><b>DWORD</b><br>
The Win32 API designation for a 32-bit integer.</p><p><b>dynamic binding</b><br>
Binding (converting symbolic addresses in the program to
storage-related addresses) that occurs during program execution.
The term often refers to object-oriented applications that
determine, during run time, which software routines to call for
particular data objects. Also called late binding.</p><p><b>Dynamic Host Configuration Protocol (DHCP)</b><br>
A TCP/IP protocol that enables a network connected to the Internet
to assign a temporary IP address to a host automatically when the
host connects to the network.</p><p><b>dynamic HTML (DHTML)</b><br>
A set of innovative features in Internet Explorer version 4.0 and
later that can be used to create HTML documents that dynamically
change their content and interact with the user. By using DHTML,
authors can provide special effects on a Web page without relying
on server-side programs.</p><p><b>dynamic-link library (DLL)</b><br>
A feature of the Microsoft Windows family of operating systems
that supports executable routines-usually serving a specific
function or set of functions-to be stored separately as files with
the file extension name .dll, and to be loaded only when called by
the program that needs them. This saves memory during program
execution and enables code reusability.</p><p><b>dynamic page</b><br>
An HTML document that contains animated GIFs, Java applets,
ActiveX Controls, or DHTML. Also, a Web page created automatically
based on information provided by the user, or generated "on the
When the failed server node is fully restored to action.
<p><b>failover</b><br>
When one individual computer fails, another automatically takes
over its request load. The transition is invisible to the user.</p><p><b>FAQ</b><br><i>See</i><b>Frequently Asked Questions</b>.</p><p><b>fat server</b><br>
In a client/server architecture, a server computer that performs
most of the processing, with little or none performed by the
client.</p><p><b>fault tolerance</b><br>
The ability of a computer or an operating system to respond to a
catastrophic event or fault, such as a power outage or a hardware
failure, in a way that ensures that no data is lost or corrupted.
This can be accomplished with a battery-backed power supply, backup
hardware, provisions in the operating system, or any combination of
these. In a fault-tolerant network, the system has the ability
either to continue the system's operation without loss of data; or
to shut the system down and restart it, recovering all processing
that was in progress when the fault occurred. See also <b>
Usually a document containing questions and answers that address
basic questions. A visitor can find an FAQ on many Web sites. An
FAQ serves to introduce a visitor to the topic or subject of the
Web site and to offer general guidelines about how to best use the
site.</p><p><b>friendly name</b><br>
Also called a host name. A name that substitutes for an IP
address, for example, www.microsoft.com instead of
172.16.255.255.</p><p><b>FrontPage Server Extensions</b><br>
A group of files installed on an HTTP service to give that service
the ability to provide special Microsoft FrontPage functionality.
With FrontPage Server Extensions, administrators can view and
manage a Web site in a graphical interface. Also, authors can
create, edit, and post Web pages to IIS remotely.</p><p><b>FTP</b><br><i>See</i><b>File Transfer Protocol</b>.</p><h1><a name="H1_37725387"></a><a href="#glossary"><b><img src="art/up.gif" alt="To Top"></b></a><a name="GlossaryG"><b>G</b></a></h1><b>gateway</b><br>
A device that connects networks using different communications
protocols so that information can be passed from one to the other.
A gateway both transfers information and converts it to a form
compatible with the protocols used by the receiving network.
In COM, a 16-byte code that identifies an interface to an object
across all computers and networks. Such an identifier is unique
because it contains a time stamp and a code based on the network
address hard-wired on the host computer's LAN interface card. These
identifiers are generated by a utility program.</p><p><b>Gopher</b><br>
An early Internet protocol and software program designed to search
for, retrieve, and display text documents from remote computers or
sites.</p><p><b>graphical user interface (GUI)</b><br>
A type of environment that represents programs, files, and options
by means of icons, menus, and dialog boxes on the screen. The user
can select and activate these options by pointing and clicking with
a mouse or, often, with a keyboard.</p><p><b>Graphics Interchange Format (GIF)</b><br>
A computer graphics file format developed in the mid-1980s by
CompuServe for use in photo-quality graphic image display on
computer screens. Now commonly used on the Internet.</p><p><b>GUI</b><br><i>See</i><b>graphical user interface</b>.</p><p><b>GUID</b><br><i>See</i><b>globally unique identifier</b>.</p><h1><a name="H1_37726175"></a><a href="#glossary"><b><img src="art/up.gif" alt="To Top"></b></a><a name="GlossaryH"><b>H</b></a></h1><b>handshake</b><br>
A series of signals acknowledging that communication or the
transfer of information can take place between computers or other
devices. A hardware handshake is an exchange of signals over
specific wires (other than the data wires), in which each device
indicates its readiness to send or receive data. A software
handshake consists of signals transmitted over the same wires used
to transfer data, as in modem-to-modem communications over
telephone lines.
<p><b>hash value</b><br>
A small amount of binary data, typically around 160 bits, derived
from a message by using a hashing algorithm. The hashing procedure
is one-way. There is no feasible way of deriving the original
message, or even any of its properties, from the hash value, even
given the hashing algorithm. The same message will always produce
the same hash value when passed through the same hashing algorithm.
Messages differing by even one character can produce very different
hash values.</p><p><b>hash value comparison</b><br>
When a client or server receives a hash value as part of an
authentication scheme it will use a commonly known key value, such
as a password, to create a hash value and compare the generated
hash value with the one it received. If they are identical,
authentication is accepted. See also <b>replication</b>.</p><p><b>heap (Windows heap)</b><br>
An area of working memory provided by Windows that applications can
use to store data.</p><p><b>hit</b><br>
A successful retrieval of data from a cache rather than from the
slower hard disk or RAM; a successful retrieval of a record
matching a query in a database; or the retrieval of a document,
such as a home page, from a Web site. See also <b>usage
data</b>.</p><p><b>home directory</b><br>
The root directory for a Web site, where the content files are
stored. Also called a document root or Web root. In Internet
Information Services, the home directory and all its subdirectories
are available to users by default. Also the root directory for an
IIS service. Typically the home directory for a site contains the
home page. See also <b>home page</b>.</p><p><b>home page</b><br>
The initial page of information for a collection of pages, a Web
site or section of a Web site. See also <b>default
document</b>.</p><p><b>host</b><br>
The main computer in a system of computers or terminals connected
by communications links.</p><p><b>host name</b><br>
The name of a specific server on a specific network within the
Internet, leftmost in the complete host specifications. For
example, www.microsoft.com indicates the server called "www" within
the network at the Microsoft Corporation.</p><p><b>HTML</b><br><i>See</i><b>Hypertext Markup Language</b>.</p><p><b>HTTP</b><br><i>See</i><b>Hypertext Transfer Protocol</b>.</p><p><b>HTTPD</b><br>
HTTP Daemon; a Web server.</p><p><b>HTTP header</b><br>
An informational listing at the top of an HTTP request or
response.</p><p><b>hyperlink</b><br>
A connection between an element in a hyptertext document, such as
a word, phrase, symbol, or image, and a different element in the
document, another hypertext document, a file, or a script. The user
activates the link by clicking on the linked element, which is
usually underlined or in a color different from the rest of the
document. Hyperlinks are indicated in a hypertext document by the
use of tags in markup languages such as SGML and HTML. These tags
are generally not visible to the user. Also called hot links and
hypertext links.</p><p><b>hypertext</b><br>
Text linked together in a complex, nonsequential web of
associations in which the user can browse through related topics.
The term hypertext was coined in 1965 to describe documents
presented by a computer that express the nonlinear structure of
ideas as opposed to the linear format of books, film, and
speech.</p><p><b>Hypertext Markup Language (HTML)</b><br>
A simple markup language used to create hypertext documents that
are portable from one platform to another. HTML files are simple
ASCII text files with codes embedded (indicated by markup tags) to
indicate formatting and hypertext links. The formatting language
used for documents on the World Wide Web. See also <b>Dynamic
Any protocol for transferring information over the Internet,
except HTTP. The protocol is the first part of the full URL for a
resource. Internet service types include Gopher, telnet, WAIS,
NNTP, HTTP, and FTP. See also <b>Hypertext Transfer Protocol</b>;
<b>protocol</b>.</p><p><b>Internet service provider (ISP)</b><br>
Public provider of remote connections to the Internet. A company
or educational institution that enables remote users to access the
Internet by providing dial-up connections or installing leased
lines.</p><p><b>interoperability</b><br>
The ability of software and hardware on multiple computers from
multiple vendors to communicate meaningfully.</p><p><b>intranet</b><br>
A network designed for information processing within a company or
organization. Its uses include such services as document
distribution, software distribution, access to databases, and
training. An intranet is so called because it usually employs
applications associated with the Internet, such as Web pages, Web
browsers, FTP sites, e-mail, newsgroups, and mailing lists, in this
case accessible only to those within the company or
organization.</p><p><b>IP</b><br><i>See</i><b>Internet Protocol</b>.</p><p><b>ISAPI</b><br><i>See</i><b>Internet Server Application Programming Interface
(ISAPI)</b>.</p><p><b>ISDN</b><br><i>See</i><b>Integrated Services Digital Network</b>.</p><p><b>ISO/OSI model</b><br><i>See</i><b>International Organization for Standardization Open
Systems Interconnection model</b>.</p><p><b>ISP</b><br><i>See</i><b>Internet service provider</b>.</p><h1><a name="H1_37732303"></a><a href="#glossary"><b><img src="art/up.gif" alt="To Top"></b></a><a name="GlossaryJ"><b>J</b></a></h1><b>Java</b><br>
An object-oriented programming language developed by Sun
Microsystems, Inc. Currently, the most widespread use of Java is in
programming small applications, or applets, for the World Wide Web.
<p><b>JavaBeans</b><br>
An object model being developed by SunSoft that is targeted to
interoperate with a variety of other object models, including COM
and CORBA. See also <b>Common Object Request Broker
Software on a computer that runs Java applets.</p><p><b>JDBC</b><br><i>See</i><b>Java Database Connectivity</b>.</p><p><b>JIT</b><br><i>See</i><b>just-in-time activation</b>.</p><p><b>Joint Photographic Experts Group (JPEG)</b><br>
An ISO/ITO standard for storing images in compressed form using a
discrete cosine transform. JPEG trades off compression against
loss; it can achieve a compression ratio of 100:1 with significant
loss and up to 20:1 with little noticeable loss.</p><p><b>JPEG</b><br><i>See</i><b>Joint Photographic Experts Group</b>.</p><p><b>JScript</b><br>
The Microsoft open implementation of JavaScript. JScript complies
with the ECMA 262 language specification.</p><p><b>just-in-time activation (JIT)</b><br>
The ability of a COM object to be activated only as needed for
executing requests from its client. Objects can be deactivated even
while clients hold references to them, allowing otherwise idle
server resources to be used more productively.</p><h1><a name="H1_37733691"></a><a href="#glossary"><b><img src="art/up.gif" alt="To Top"></b></a><a name="GlossaryK"><b>K</b></a></h1><b>Keep-Alive connection</b><br>
An HTTP connection that is not closed after an exchange is
completed.
<p><b>Kerberos protocol</b><br>
The basis of Windows security, for both internal and intranet
logon. The Kerberos protocol provides for the secure use of
distributed software components. See also <b>cryptography</b>; <b>
encryption</b>.</p><p><b>key</b><br>
A node in the Windows registry or IIS metabase. A key can contain
subkeys and value entries. For example: Environment is a key of
HKEY_CURRENT_USER.</p><p><b>key pair</b><br>
The combination of private and public encryption keys that
provides verification of the source of data sent across a network.
See also <b>certificate, client</b>; <b>digital signature</b>; <b>
session key</b>.</p><p><b>keyword</b><br>
In search-engine technology, a significant word, which is used for
content indexing; see also <b>noise word</b>. In programming, a
word reserved for a command or other program instruction.</p><p><b>keyword index</b><br>
A file of significant words appearing in documents; used for
keyword searches.</p><h1><a name="H1_37734950"></a><a href="#glossary"><b><img src="art/up.gif" alt="To Top"></b></a><a name="GlossaryL"><b>L</b></a></h1><b>LAN</b><br><i>See</i><b>local area network</b>.
services within Windows Open Services Architecture (WOSA).</p><p><b>Management Information Base (MIB)</b><br>
Information about aspects of a network that can be managed by
using the Simple Network Management Protocol (SNMP). This
information is formatted in MIB files that are provided for each
service that can be monitored. Most third-party monitors (clients)
use SNMP and MIB files to monitor Web, FTP, and other Windows
services. Using the SNMP protocol, a developer or system
administrator can write their own custom monitoring
applications.</p><p><b>MAPI</b><br><i>See</i><b>Mail or Messaging Applications Programming
Interface</b>.</p><p><b>marshaling</b><br>
The process of packaging and sending interface method parameters
across thread or process boundaries.</p><p><b>master properties</b><br>
In IIS, properties that are set at the computer level that become
default settings for all Web or FTP sites on that computer. See
also <b>inheritance</b>.</p><p><b>MDAC</b><br><i>See</i><b>Microsoft Data Access Components</b>.</p><p><b>Message Digest 5 (MD5)</b><br>
An encryption method used on the Internet.</p><p><b>message passing</b><br>
A method for processes running in parallel to interact with one
another.</p><p><b>Message Queuing</b><br>
A server technology that developers can use to build large-scale
distributed systems with reliable communications between
applications that can continue to operate even when networked
systems are unavailable.</p><p><b>meta-authoring environment</b><br>
A term sometimes used for the process of both authoring Web pages
and setting up a Web site.</p><p><b>metabase</b><br>
A structure for storing IIS configuration settings; the metabase
performs some of the same functions as the system registry, but
uses less disk space.</p><p><b>metadata</b><br>
Data used to describe other data. For example, Indexing Service
must maintain data that describes the data in the content
index.</p><p><b>method</b><br>
A procedure (function) that acts on an object.</p><p><b>MIB</b><br><i>See</i><b>Management Information Base</b>.</p><p><b>Microsoft Cryptographic API</b><br>
An application programming interface providing services for
authentication, encoding, and encryption in Win32-based
applications.á See also <b>Cryptographic Service Provider</b>,
<b>encryption</b>.</p><p><b>Microsoft Data Access Components (MDAC)</b><br>
Consists of ActiveX Data Objects (ADO), the Remote Data Service
(RDS), Microsoft OLE DB Provider for ODBC, Open Database
Connectivity (ODBC), ODBC drivers for Microsoft SQL Server,
Microsoft Access and other desktop databases, as well as Oracle
In client/server applications, an interface to which the client
makes a request for an object. The ORB directs the request to the
server containing the object and then returns the resulting values
to the client.</p><p><b>octet</b><br>
Eight contiguous bits, or a byte. The term was created because
some computer systems attached to the Internet used a byte with
more than eight bits.</p><p><b>ODBC</b><br><i>See</i><b>Open Database Connectivity</b>.</p><p><b>OID</b><br><i>See</i><b>Object Identifiers</b>.</p><p><b>OLE</b><br><i>See</i><b>Object Linking and Embedding</b>.</p><p><b>OLE DB</b><br><i>See</i><b>Object Linking and Embedding Database</b>.</p><p><b>OMG</b><br><i>See</i><b>Object Management Group</b>.</p><p><b>Open Database Connectivity (ODBC)</b><br>
An application programming interface that enables applications to
access data from a variety of existing data sources. A standard
specification for cross-platform database access.</p><p><b>Open Group, The</b><br>
The parent company of a number of standards organizations
including The Active Group. The Open Group now manages the core
ActiveX technology, X/Open, and the Open Software Foundation
A UNC directory path with placeholders, or wildcards, at some
levels. The term relative path is also sometimes used to mean the
physical path that corresponds to a URL. See also <b>Uniform
Resource Locator</b>.</p><p><b>path, URL</b><br>
A term sometimes used for the full URL submitted to the server; a
URL path may or may not include a specific file name. See also <b>
Uniform Resource Locator</b>.</p><p><b>PDH</b><br><i>See</i><b>Performance Data Helper</b>.</p><p><b>Perfmon</b><br><i>See</i><b>Performance Monitor</b>.</p><p><b>Performance Counters</b><br>
Counters are references that measure the performance of
applications, services, or drivers. Counters can be monitored using
protocol interfaces such as PDH or SNMP, or by using the
Performance Monitor MMC snap-in (Perfmon).</p><p><b>Performance Data Helper</b><br>
A network monitoring protocol in Windows. Performance monitoring is
the process of capturing and analyzing the performance data that
applications, services, and drivers provide. The data can be used
to determine the cause of system bottlenecks and to fine-tune
system and application performance. PDH is an interface for
accessing this data. The Windows Performance Monitor (Perfmon) uses
PDH. See also <b>Simple Network Management Protocol</b>.</p><p><b>Performance Monitor</b><br>
An MMC snap-in that shows real-time data and logs from Performance
Counters. The data can be used to determine the cause of system
bottlenecks and to fine-tune system and application performance.
Counters can be added and removed from the display, or configured
to log in a certain way. See also <b>Performance Counters,
Performance Data Helper</b>.</p><p><b>Perl</b><br>
Practical Extraction and Report Language. An interpreted language,
based on C and several UNIX utilities. Perl has powerful
string-handling features for extracting information from text
files. Perl can assemble a string and send it to the shell as a
command; hence, it is often used for system administration tasks. A
program in Perl is known as a script. Perl was devised by Larry
Wall at NASA's Jet Propulsion Laboratory. See also <b>
script</b>.</p><p><b>PGP</b><br><i>See</i><b>Pretty Good Privacy</b>.</p><p><b>physical transaction</b><br>
The actual updating of the data resources that are used to record a
logical transaction.</p><p><b>PING</b><br><i>See</i><b>Packet INternet Groper</b>.</p><p><b>Point-to-Point Protocol (PPP)</b><br>
A set of industry-standard framing and authentication protocols
included with Windows Remote Access Service (RAS) to ensure
interoperability with third-party remote access software. PPP
negotiates configuration parameters for multiple layers of the OSI
(Open Systems Interconnection) model. The Internet standard for
serial communications, PPP defines how data packets are exchanged
with other Internet-based systems using a modem connection.</p><p><b>Point-to-Point Tunneling Protocol (PPTP)</b><br>
A specification for virtual private networks in which some nodes
of a local area network are connected through the Internet. PPTP is
an open industry standard that supports the most prevalent
networking protocols-IP, IPX, and Microsoft Networking (NetBEUI).
Companies can use PPTP to outsource their remote dial-up needs to
an Internet service provider or other carrier to reduce cost and
complexity.</p><p><b>policies</b><br>
Conditions set by the system administrator such as how quickly
account passwords expire and how many unsuccessful logon attempts
are allowed before a user is locked out. These policies manage
accounts to prevent exhaustive or random password attacks.</p><p><b>port number</b><br>
A number identifying a certain Internet application. For example,
the default port number for the WWW service is 80.</p><p><b>PPP</b><br><i>See</i><b>Point-to-Point Protocol</b>.</p><p><b>PPTP</b><br><i>See</i><b>Point-to-Point Tunneling Protocol</b>.</p><p><b>Pretty Good Privacy (PGP)</b><br>
A security application that uses public-key encryption. See also
Semiconductor-based memory that can be read and written by the
central processing unit (CPU) or other hardware devices. The
storage locations can be accessed in any order. Note that various
types of ROM memory are capable of random access but cannot be
written to. The term RAM is generally understood to refer to
volatile memory that can be written to as well as read. Information
stored in RAM is lost when the user turns off the computer.</p><p><b>RARP</b><br><i>See</i><b>Reverse Address Resolution Protocol</b>.</p><p><b>RAS</b><br><i>See</i><b>Remote Access Service</b>.</p><p><b>realm</b><br>
A term sometimes used for domain, in this case to refer to user
domains established for security reasons, not Internet domains. For
password-protected files, the name of the protected resource or
area on the server. If the user tries to access the protected
resource while browsing, the name of the realm usually appears in
the dialog box that asks for a user name and password.</p><p><b>redirection</b><br>
The process of writing to or reading from a file or device
different from the one that would normally be the target or the
source. Can be used to automatically send a user from an outdated
URL to a new one.</p><p><b>Redundant Array of Independent Disks (RAID)</b><br>
A data storage method in which data, along with information used
for error correction, such as parity bits, is distributed among two
or more hard disk drives in order to improve performance and
reliability. The hard disk array is governed by array management
software and a disk controller, which handles the error correction.
RAID is generally used on network servers. Several defined levels
of RAID offer differing trade-offs among access speed, reliability,
and cost. Windows includes three of the RAID levels: Level 0, Level
1, and Level 5.</p><p><b>registry</b><br>
A central hierarchical database in Windows used to store
information necessary to configure the system for one or more
users, applications, and hardware devices. The registry contains
information that is constantly referenced during operation, such as
profiles for each user, the applications installed on the computer;
and the types of documents each can create, property sheet settings
for folders and application icons, what hardware exists on the
system; and which ports are being used.</p><p><b>Remote Access Service (RAS)</b><br>
A service that allows remote clients running Microsoft Windows to
dial-in to a network. See also <b>dial-up</b>.</p><p><b>Remote Data Services</b><br>
A Web-based technology that brings database connectivity and
corporate data publishing capabilities to Internet and intranet
A log, generated by a firewall or other security device, that lists
events that could affect security, such as access attempts or
commands, and the information about the users involved.</p><p><b>Selectable Cryptographic Service Provider</b><br><i>See</i><b>Cryptographic Service Provider</b>.</p><p><b>semaphore</b><br>
A locking mechanism used inside resource managers or resource
dispensers. Semaphores have no symbolic names-only shared and
exclusive mode access-no deadlock detection, and no automatic
release or commit.</p><p><b>server</b><br>
A term used for any of the following: a computer on a network that
sends files to, or runs applications for, other computers on the
network; the software that runs on the server computer and performs
the work of serving files or running applications; or, in
object-oriented programming, a piece of code that exchanges
information with another piece of code upon request.</p><p><b>server certificate</b><br>
A unique digital identification that forms the basis of a Web
server's SSL security features. Server certificates are obtained
from a mutually trusted, third-party organization, and provide a
way for users to authenticate the identity of a Web site.</p><p><b>server cluster</b><br>
A group of server computers that are networked together both
physically and with software, in order to provide cluster features
such as fault tolerance or load balancing. See also <b>fault
A model in which all objects are executed on a single thread.</p><p><b>sitename</b><br><i>See</i><b>host name</b>.</p><p><b>slow link</b><br>
A modem connection, usually from 14,400 bps to 56,000 bps.</p><p><b>SMTP</b><br><i>See</i><b>Simple Mail Transfer Protocol</b>.</p><p><b>SNA</b><br><i>See</i><b>Systems Network Architecture</b>.</p><p><b>snap-in</b><br>
Snap-ins are programs hosted within Microsoft Management Console
(MMC) that administrators use to manage network services. The MMC
provides the environment in which management tools (snap-ins) are
hosted; snap-ins provide the actual management behavior necessary
to administer network services such as IIS.</p><p><b>sniffer</b><br><i>See</i><b>network sniffer</b>.</p><p><b>SNMP</b><br><i>See</i><b>Simple Network Management Protocol</b>.</p><p><b>socket</b><br>
An identifier for a particular service on a particular node on a
network. The socket consists of a node address and a port number,
which identifies the service. For example, port 80 on an Internet
node indicates a Web server.</p><p><b>spider</b><br>
A fast, automated program-such as a search engine, indexing
program, or cataloging software-that requests Web pages much faster
than human beings can. Other commonly used terms for spider are
crawler and robot.</p><p><b>spoofing</b><br>
Impersonating another person or computer, usually by providing a
false e-mail name, URL, or IP address.</p><p><b>SQL</b><br><i>See</i><b>Structured Query Language</b></p><p><b>SQL Access Group (SAG)</b><br>
A consortium of vendors established in November 1989 to accelerate
the Remote Data Access standard and to deliver protocols for
interconnectivity among multiple SQL-based software products.</p><p><b>SSL</b><br><i>See</i><b>Secure Sockets Layer</b>.</p><p><b>Standard Generalized Markup Language (SGML)</b><br>
An ISO standard (ISO 8879:1986) which supplies a formal notation
for the definition of generalized markup languages. It is an
international standard for the definition of device-independent,
system-independent methods of representing texts in an electronic
form. SGML is a metalanguage-that is, a means of formally
describing a language, in this case, a markup language. See also
<b>Hypertext Markup Language</b>; <b>International Organization for
An object that holds private state accumulated from the execution
of one or more client calls.</p><p><b>stateless object</b><br>
An object that does not hold private state accumulated from the
execution of one or more client calls.</p><p><b>static binding</b><br>
Binding (converting symbolic addresses in the program to
storage-related addresses) that occurs during program compilation
or linkage.</p><p><b>static page</b><br>
HTML pages prepared in advance of the request and sent to the
client upon request. This page takes no special action when
requested. See also <b>dynamic page</b>.</p><p><b>stripe set</b><br>
Refers to the saving of data across identical partitions on
different drives. A stripe set does not provide fault tolerance;
however, stripe sets with parity do provide fault tolerance. See
also <b>fault tolerance</b>; <b>partition</b>; <b>stripe sets with
parity</b>.</p><p><b>stripe sets with parity</b><br>
A method of data protection in which data is striped in large
blocks across all the disks in an array. Data redundancy is
provided by the parity information. This method provides fault
tolerance. See also <b>fault tolerance</b>; <b>stripe set</b>.</p><p><b>Structured Query Language (SQL)</b><br>
The international standard language for defining and accessing
relational databases.</p><p><b>stub</b><br>
A routine that contains no executable code and that generally
consists of comments describing what will eventually be there; it
is used as a placeholder for a routine to be written later.</p><p><b>subnet mask</b><br>
A TCP/IP configuration parameter that extracts network and host
configuration from an IP address.</p><p><b>System Data Source Name (DSN)</b><br>
A name that can be used by any process on the computer. IIS uses
system DSNs to access ODBC data sources.</p><p><b>System Monitor</b><br><i>See</i><b>Performance Monitor</b>.</p><p><b>Systems Network Architecture (SNA)</b><br>
A widely used communications framework developed by IBM to define
network functions and to establish standards for enabling its
different models of computers to exchange and process data. SNA
contains separate layers. As changes occur in one layer, no other
layer need be changed.</p><h1><a name="H1_37757909"></a><a href="#glossary"><b><img src="art/up.gif" alt="To Top"></b></a><a name="GlossaryT"><b>T</b></a></h1><b>T1</b><br>
A U.S. telephone standard for a transmission facility at digital
signal level 1 (DS1) with 1.544 Mbps in North America and 2.048
Mbps in Europe. The bit rate is with the equivalent bandwidth of
approximately twenty-four 56 Kbps lines. A T1 circuit is capable of
serving a minimum of 48 modems at 28.8 Kbps, or 96 modems at 14.4
Kbps. T1 circuits are also used for voice telephone connections. A
single T1 line carries 24 telephone connections with 24 telephone
numbers. When used for voice transmission, a T1 connection must be
split into 24 separate circuits.
<p><b>T3</b><br>
A U.S. telephone standard for a transmission facility at digital
signal level 3 (DS3). Equivalent in bandwidth to 28 T1s. The bit
rate is 44.736 Mbps. T3 is sometimes called a 45-meg circuit.</p><p><b>TCP/IP</b><br><i>See</i><b>Transmission Control Protocol/Internet
Protocol</b>.</p><p><b>telnet</b><br>
A protocol that enables an Internet user to log onto and enter
commands on a remote computer linked to the Internet, as if the
user were using a text-based terminal directly attached to that
computer. Telnet is part of the TCP/IP suite of protocols.</p><p><b>10BaseT</b><br>
A variant of Ethernet which allows stations to be attached by a
twisted-pair cable.</p><p><b>thin server</b><br>
A client/server architecture in which most of an application is run
on the client computer, which is called a fat client, with
occasional data operations on a remote server. Such a configuration
yields good client performance but complicates administrative tasks
such as software upgrades. See also <b>fat server</b>.</p><p><b>thread</b><br>
The basic entity to which the operating system allocates CPU time.
A thread can execute any part of the application's code, including
a part currently being executed by another thread. All threads of a
process share the virtual address space, global variables, and
operating-system resources of the process.</p><p><b>three-tier architecture</b><br>
Divides a networked application into three logical areas: the user
interface layer, the business logic layer, and the database layer.
Layers may have one or more components. For example, there can be
one or more user interfaces in the top tier, each user interface
may communicate with more than one application in the middle tier
at the same time, and the applications in the middle tier may use
more than one database at a time. Components in a tier may run on a
computer that is separate from the other tiers, communicating with
the other components over a network.</p><p><b>throttling</b><br>
Controlling the maximum amount of bandwidth dedicated to Internet
traffic on a server. This feature is useful if there are other
services (such as e-mail) sharing the server over a busy link.</p><p><b>thumbnail</b><br>
A small version of a graphic with a hyperlink to a larger version
of the same graphic.</p><p><b>time-out</b><br>
A setting that automatically cancels an unanswered client request
after a certain period of time.</p><p><b>token ring</b><br>
A type of network with nodes wired into a ring. Each node
constantly passes a control message (token) on to the next;
whichever node has the token can send a message. Often, "token
ring" is used to refer to the Institute of Electrical and
Electronics Engineers (IEEE) 802.5 token ring standard, which is
the most common type of token ring. See also <b>local area
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