Fiber Optics Illustrated Dictionary - Part 52 doc

Established in 1983 to replace the Internet Configuration Control Board, the lAB subsequently came under the umbrella ofthe Internet Architecture Board.. Formerly the In-ternet Activitie

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Fiber Optics Illustrated Dictionary

generation ofthe Internet on a content and integration

level For information on the technical successor to

the current Internet protocols and physical structures,

see IPv6 http://www.internet2.eduJ

Internet Access CoalitionlAC A lobbying

organi-zation that supports universal Internet access and

monitors and comments on industry trends in

Inter-net services provision, long-distance access, and other

logistical matters that affect the ability of the public

to access and utilize Internet services The lAC

some-times works in cooperation with other organizations

such as the Information Technology Association of

America (ITAA)

Internet Access ProviderlAP A vendor who

pro-vides a connection to the Internet in the form ofFrame

Relay, ISDN, a dialup modem, or other physical or

virtual connection, and who mayor may not provide

additional services, such as email, shell accounts, web

hosting, etc Providers with full services available,

rather than just an access port to the Internet, are

gen-erally called Internet Services Providers (ISPs) See

Internet Services Provider

Internet Activities BoardlAB Established in 1983

to replace the Internet Configuration Control Board,

the lAB subsequently came under the umbrella ofthe

Internet Architecture Board See Internet

Architec-ture Board

Internet Architecture BoardlAB Formerly the

In-ternet Activities Board (and before that, the InIn-ternet

Configuration Control Board), the lAB is a

coordi-nating and policy-setting board for the Internet

En-gineering Task Force (IETF) and the Internet

Re-search Task Force (IRTF) All three bodies were

com-bined under the aegis of the Internet Society (ISOC)

in the early 1990s and the lAB is now the technical

advisor to the Internet Society See RFC 1358 for a

charter of the lAB, and RFC 1160 for a description

of its organization and role See Internet

Engineer-ing Task Force (IETF), Request for Comments

http://www.isi.eduJiab/

Internet Assigned Numbers AuthoritylANA.An

organization which, since the early 1980s, has

exer-cised authority over DNS operations, Internet

Proto-col (IF) number assignment, Root Name Servers,

Request for Comments (RFC) documents, and

pro-tocol port number assignments lANA is the central

coordinator for the assignment ofunique numbers for

Internet protocols and serves as a clearinghouse for

this purpose

lANA also provides registration through a central

repository for MIME types, that is, data object types

identified by a short ASCII string which can be used

to provide rich content types in conjunction with

elec-tronic mail

Jon Postel has almost single-handedly spearheaded

this effort, an enormous contribution by an Internet

pioneer involved since the days of the ARPANET

lANA is chartered by the Internet Society (ISOC) and

located at the Information Sciences Institute (lSI) of

the University of Southern California See domain

name, naming authority, name resolution

http://www.iana.org/iana/

Internet Channel Commerce Connectivity Proto-col ICCC A channel-based connectivity protocol designed to facilitate electronic commerce, initiated

by 3Com ICCC is intended as a scalable, securable, channel-based electronic commerce infrastructure, based upon Extensible Markup Language (XML) Access to ICCC is through popular Internet brows-ers so that WWW-related Internet commerce appli-cations can be built upon ICCC

The concept is of an application-layer protocol that passes over the wire, to promote interoperability, with transactions accomplished through the widely estab-lished HTTP "Shopping cart" programs on the Web illustrate the general idea of what ICCC is intended

to accomplish through a standardized protocol model using existing standardized formats and a server-to-server transfer (rather than through the browser) See Open Buying on the Internet, Open Financial Ex-change, Open Trading Protocol

Internet Community at Large ICAL A project funded by the National Science Foundation Division ofEnvironmental Biology's Research Collections in Systematics& Ecology Program through the Mu-seum ofPaleontology at Berkeley to facilitate devel-opment ofimproved and new modes of communica-tion among museums, donors, and research scientists, utilizing the World Wide Web The main purpose of the Web project is to help reduce the number of or-phaned or underutilized natural history collections Additional support for ICAL-Entomology was pro-vided by the National Science Foundation through the Bishop Museum

Internet Configuration Control BoardICCB A regulatory board established by the U.S DARPA in the late 1970s to facilitate the creation of gateways between hosts and the network The ICCB was re-placed by the Internet Activities Board in 1983 See ARPANET, DARPANET

Internet Control Message ProtocolICMP A sig-nificant protocol in that it is an IETF-required stan-dard on the Internet for reporting and error messages

in Internet Protocol (IP) datagram routing While not

a reliability guarantee, ICMP can provide feedback regarding problems in datagram processing and de-livery ICMP messages are contained in the basic IP header Examples include information on whether the destination is reachable, echo or redirect situations exist, time has been exceeded, or a problem exists with a parameter

Currently the Net is run over IPv4, and migration to IPv6 is planned ICMP for IPv6 is based on the same definition with some changes and is known as ICMPv6 See Classes and Format oflCMPv6 Mes-sages chart See IF, RFC 792, RFC 1788

Internet Control Message Protocol for IPv6 ICMPv6 ICMPv6 is a required and integral part of IPv6 that must be fully implemented at every node

It is used for diagnostics and error reporting ICMPv6 messages are preceded by an IPv6 header and zero

or more extension headers, identified by a Next Header value of 58 in the header immediately preceding ICMPv6 messages are organized into two

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ICMPv6 Messages chart See RFC 792.

Internet Corporation for Assigned Names and

NumbersICANN Anot-for-profit organization

es-tablished asaresult ofstudies and recommendations

reported in the White Paper issued by the National

Telecommunications and Infonnation Administration

(NTIA) oftheU.S.Department ofCommerce in June

1998 This was a significant step in privatizing

man-agement of the Internet domain name system Amid

discussions with other organizations such as the

World Intellectual Property Organization (WIPO),

ICANN developed policy and procedural guidelines

for management ofthe Internet domain name system

worldwide One of the significant outcomes was the

April 1999 announcement of a testbed for a Shared

Registry System to be administered by five

compa-nies rather than one, with Network Solutions, Inc to

continue to maintain the registry database in order to

ensure a centralized repository for unique domain

names See White Paper http://www.icann.org/

Internet Engineering Steering GroupIESG The

executive governing body of the Internet

Engineer-ing Task Force (IETF) and technical overseer for the

Internet standards process, including final approval

The IESG is a member ofthe Internet Society (ISOC)

and works within ISOC rules and procedures See

Internet Architecture Board

http://www.ietf.org/iesg.html

Internet Engineering Task ForceIETF The IETF

is governed by the Internet Engineering Steering

Group (IESG).Itis a large, international open

com-munity of network researchers and designers

dedi-cated to the positive evolution of Internet

architec-ture and operations

ment and standardization body

The IETF has worked long and hard onIPVersion 6 with the intention that it supersede IPv4 In 1997, the IETF made some significant changes to support more dynamic addressing schemes Several draft standards for IPv6 were submitted in December 1998 followed

by many proposed standards in 1998 and 1999 These are moving slowly through the standardization and implementation process In the meantime, some ad-justments have been made to lengthen the life ofVer-sion 4, which has address space limitations, so that it can continue to be a viable networking solution until vendors begin to implement and support IPv6 into the new century See Internet Architecture Board, Re-quest for Comments

http://www.ietf.org/home.html

Network Information Center (NIC)

Internet FaxThe terminology and goals for the de-velopment ofInternet Fax systems and guidelines for the Internet Fax working group were submitted as an Informational RFC by L Masinter in March 1999

Internet Fax is described as a document transmission mechanism between various devices and roles which may be differently configured Several general cat-egories of roles were defined as network scanner, network printer, fax onramp gateway, and fax offtamp gateway The common modes for Internet Fax were described as store and forward, session, and realtime

To support the concept of deploying facsimile ser-vices over the Internet, Klyne and McIntyre submit-ted a Standards TrackRFC in March 1999 describing Classes and Format of ICMPv6 Messages

Type of Message

Error message

Infonnational message

Identification of Type

Zero in the high-order bit

of the message "Type" field

Message Type Number

oto 127

128to 255 ICMPv6 messages have the following fonnat:

0 1 2 3 4 5 6 7 8 9 012 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 901

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type

Code

Checksum

The type of message Its value determines the fonnat of the remaining data

Depends upon the message type Used to create an additionallevel of message granularity

Used to detect data corruption in the ICMPv6 message and parts of the IPv6 header

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content feature schema for Internet Fax as a profile

of a media feature registration mechanism for

per-forming capability identification between extended

Internet Fax systems This was updated in August

2000 See RFC 2542, RFC 2879 (which obsoletes

RFC 2531)

Internet Free Expression AllianceIFEA.An

orga-nization promoting a liberal computer

communica-tions environment in order to facilitate and safeguard

the Internet as a free, open, and diverse forum for the

exchange of discussions and data

http://www.ifea.net

Internet Group Multicast ProtocolIGMP An

IETF-recommended session-layer protocol for

net-work transmissions to multiple sites IGMP is a

dy-namic protocol that provides a means for end systems

to request inclusion in a multicast group or video/data

stream conference (group broadcast) A host can

re-quest membership into one or more groups at the

same time It can transmit datagrams to a group

with-out necessarily having requested membership to that

group See RFC 1112, RFC 2236

Internet Information Infrastructure Architecture

lIlA.A framework and support system for

informa-tion about Internet resources Uniform resource

names, characteristics, and locators are functional

categorizations within this architecture, intended to

facilitate the location of the desired information

re-sources See RFC 1737

Internet International Ad Hoc CommitteeIAHC

The IAHC was a coalition of members of the

Inter-net community cooperating to develop

recommenda-tions for the expansion ofthe Internet Domain Name

System (DNS) It published a number of guidelines

between 1996 and May 1997, made its Final Report

in February 1997, and was dissolved in May 1997

http://www.iahc.orgl

Internet Message ProtocolIMP This is one of the

historic Internet protocols, submitted by1.Postel in

March 1979 It describes a means for transmitting

messages between message processing modules over

interconnected networks Message processing

mod-ules are processesinhost computers located in

dif-ferent networks that comprise a framework for

inter-network message delivery IMP was developed in the

context of ARPA work in interconnecting networks

and was tendered by Postel as a more general

inter-nal mechanism underlying a variety ofuser-interface

programs, thus providing a messaging system

suit-able for heterogenous distributed networks like the

Internet that was to evolve out of the ARPANET

IMP was intended to support an environment in which

processes run in hosts interconnected by gateways,

with each network having many different hosts The

gateways are assumed to have minimal knowledge

of which hosts are within their associated networks

IMP is implemented within a Message Processing

Module (MPM) MPMs exchange messages by

es-tablishing full duplex communications and sending

messages in a recognizable fixed format The user

creates a message with the chosen User Interface

Pro-gram (DIP) with commands or an editor and then

sends the message through a data structure shared with the MPM The MPM discovers the unprocessed data, examines it, and determines the outgoing link

in the route to an internal or external destination The MPM communicates through a reliable proce-dure using a transport level protocol such as TCP Internet MessagingAccess ProtocolIMAP.An elec-tronic mail protocol descended from Interactive Mail Access Protocol and used for electronic mail serv-ers It provides a means to access electronic mail and news messages archived on a mail server as a dedi-cated or shared resource Thus, an email client can access and read the mail messages on the remote server as though they were on a local storage medium

It is useful in situations where the reader is more con-cerned about reading the messages than download-ing them to the local machine, especially if the mes-sages are located at more than one site or on more than one account IMAP is somewhat competitive with Post Office Protocol (POP), but both are useful depending upon the situation POP is more appropri-ate for providing access to messages that will be regu-larly downloaded to a local machine and then deleted from the mail server archive See MIME, Post Of-fice Protocol, RFC 1730, RFC 2060

Internet Network Information CenterSee InterNIC InterNet NewsINN.AnNNTP/uuCP USENET newsreading system developed by Rich Salz for Unix systems with socket interfaces This fast news pro-gram was first released in 1992 Later, in 1995, David Barr released a number ofunofficial updates thereaf-ter, maintenance ofINN was taken over by the Inter-net Software Consortium (ISC) See C News, USENET

Internet Official Protocol StandardsThe title of a Request for Comments (RFC) document released from time to time to inform the Internet community ofthe state ofstandardization ofprotocols used in the Internet that are determined by the Internet Architec-ture Board (lAB)

The memo itself is an Internet Standard and makes somewhat obsolete previous versions of the docu-ment The document describes the standardization process, the Request for Comments documents, terms, and other important concepts and procedures related to standards used to create, maintain, update, use, and understand the Internet Updates to the docu-ments are released about once a year and are usually issued with round numbers (RFC 2900, RFC 2800, RFC 2700, etc.) to facilitate memorization and loca-tion Due to the high volume ofRFCs and standards that have been developed related to the Internet, the list includes only official protocol standards RFCs and does not constitute a complete index The list is now determined by the Internet Engineering Task Force (IETF)

Internet Open Trading ProtocolIOTP.An inter-operable framework for electronic commerce over the Internet optimized for transactions between nonac-quainted parties IOTP is independent ofthe payment system and can encapsulate and support secure chan-nel card payment, GeldKarte, Mondex, and others

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submitted by D Burdett in April 2000, and was

sup-portedbya description ofdigital signatures for IOTP

presented by Davidson and Kawatsura

In April 2001,W.Hans et al submitted an Internet

Draft for aPaymentApplication Programming

Inter-face (API) for IOTP.Itproposed a common interface

for communication between the IOTP application

core and the payment modules, increasing

interoper-ability among these modules and providing a "plugin"

mechanism for application cores

In May 2001, D Eastlake of Motorola submitted an

Internet Draft to update RFC 2801 to document and

correct errors detected since the submission of the

original specification See RFC 280 I, RFC 2802,

RFC 2803

Internet PhoneA commercial software/hardware

system from VocalTec Ltd that allows a computer

user to place a telephone voice call through the

In-ternet very much the same way that a call is placed

through traditional telephone systems The primary

difference is that the voice conversation is converted

to digital data and channeled through the user's

In-ternet Services Provider (ISP) to the network, rather

than through traditional telephone switching offices

The applications software works in conjunction with

GOLD, the Global Online Directory that stores

in-formation about Intemet Phone users who can be

con-tacted online, just as the names of traditional phone

subscribers can be accessed through a phone

direc-tory See Global Online Direcdirec-tory

Internet Policy Registration AuthorityIPRA A

top-level digital security certification authority (CA)

in the Internet certification hierarchy IPRA is

X.509-compliant

Internet Printing ProtocolIPP.Anapplication level

protocol to facilitate remote printing over distributed

networks based upon Internet technologies The IPP

model and semantics were described in an

Experi-mental RFC by deBry and others in April 1999.Itis

a simplified model, including abstract objects,

at-tributes, and operations that are independent

oftrans-port and encoding methods Essentially the model is

based upon a printer and a job object, with a job

op-tionally representing multiple documents Users can

query printer capabilities, submit jobs, get status

formation on jobs, and cancel jobs Security and

in-ternationalization aspects are also described in the

specification

The documents related to IPP include:

• Design Goals for an Internet Printing

Proto-col

• Rationale for the Structure and Model and

Protocol for the Internet Printing Protocol

• Internet Printing Protocol/I.O: Model and

Se-mantics

• Internet Printing Protocol/I.O: Encoding and

Transport

• Mapping between LPD and IPP Protocols

• Internet Printing Protocol/I.O: Implementor's

[sic] Guide

Informational RFC by Hastings and Mamos in July

1999 to aid implementors in understanding and ap-plying the information in the suite of documents re-lated to IPP semantics, encoding, etc The guide aids implementors in designing client and/or IPP object implementations and provides an order in which re-quests can be processed, in addition to error check-ing See RFC 2567, RFC 2568, RFC 2566, RFC 2565, RFC 2569, RFC 2639

Internet ProtocolIP A very significant protocol in that it is an IETF-required standard on the Internet along with the Internet Control Message Protocol (ICMP) There are other related IETF protocols, which are recommended or elective IP is very widely used in TCP/IP implementations

Internet Protocol provides addressing, segmentation and reassembly, and transport functions in conjunc-tion with a number of associated protocols Logical

IP addresses are used to identify hosts by means of network and node addresses Anumber ofcategories ofnetworks are supported as IP Classes

RFC 768 describes Internet Protocol RFC 1602 is recommended for its description ofthe Intemet stan-dards process, and RFC 2200 is a useful stanstan-dards track document for Internet Official Protocol Stan-dards that further describes the standardization pro-cess See IPv6 for more informaton and charts See

IP Class, IPv6, RFC 950, RFC 919, RFC 922, RFC 2200

Internet Protocol ConsortiumIPC The IPC admin-isters the InterOperability Lab at the University of New Hampshire for testing protocols of importance

to intercommunication on the Internet There are three testing services and 17 consortiums currently support-ing this effort Ofcurrent interest is a test lab for test-ing IPv6 implementations, the version ofIntemet Pro-tocol being phasedin to coexist with and probably eventually supersede IPv4

Internet Protocol (IP) Mobility SupportA set of media-independent protocol enhancements submit-ted as a Standards Track RFC by C Perkins, in Oc-tober 1996, and updated/extended as a PPP IPCP op-tion by Solomon and Glass in February 1998

IP Mobility Support enables transparent routing of

IP datagrams to mobile nodes on the Internet A mo-bile node is identified by a home address, regardless ofwhere it happens to be connected to the Internet at any particular time While away from the original home address, the mobile node is considered to be associated with a "care of' address in much the same way as individuals who are traveling may use a care

of address for postal mail delivery The mobile node makes its care ofaddress known by registering it with

a home agent which, in tum, sends datagrams des-tined for the mobile node through a tunneling pro-cess At the end of the tunnel, the datagrams are de-livered to the mobile node See RFC 2002, RFC 2290

Internet Protocol SuiteIPS A standardized set of protocols based on a layered model that enables In-ternet systems to intercommunicate Minimally, a

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host must implement at least one protocol from each

layer, including the application, transport, Internet,

and link layers These layers form the basic

architec-ture for managing the hardware and software

nmc-tions that enable communication over the Internet

using Internet Protocol (IP) In general, layered

mod-els are organized to illustrate more abstract

applica-tions-related concepts at the top and more basic

hard-ware-related ftmctionality and transport media at the

bottom

NASA has been conducting research to improve the

efficiency of the IPS for satellite-based networks

through its Satellite Networks and Architectures

Branch Since radio communications with satellites

involve relatively long delays, special problems are

involved in implementing IP See IPv6 See

RFC 1122, RFC 1349, RFC 1958, RFC 2502,

RFC 2600

Internet Relay Chat IRe A worldwide "realtime"

24-hour text-based communications chat link on the

Internet developed in the late 1980s by Jarkko

Oikarinen IRC was inspired in concept by MUT and

in format by BITNET Relay Chat Development

be-gan in August 1988, with the first server established

in Finland as tolsun.oulu.fi IRC IT was released in

1989 by Michael Sandrof A number of other

devel-opers released versions or variations

By 1989, IRC had more than 50,000 users In 1993,

Request for Comments (RFC) 1459 was published

to provide a consistent reference and basis for the IRC

and clients intended to conform to IRC guidelines.It

was followed in 1994 by the Client-to-Client

Proto-col (CTCP) to support IRC client communications

Many IRC servers and computer systems are

config-ured to provide a means to communicate remotely

with IRe Generally it is best to connect to one

geo-graphically close to the ISP, but some servers are

busier than others and it is sometimes a good idea to

select a low-use server that is farther away IRC is

typically accessed through port 6667

IRC is an important meeting ground for people

around the world The form of an IRC chat is

some-what like a group conversation on a teletype machine,

except that the output to the screen is much faster than

the transmission and output to a printing teletype

Many celebrities, in and out of the

telecommunica-tions industry, have been known to participate in IRC

conversations and to draw large crowds of

partici-pants around the world To join a chat (a

communi-cations channel dedicated to a specified topic), you

must have access to a provider that provides a port

to IRC, a basic understanding of how to sign onto a

chat, and a willingness to learn a few simple

com-mands

A command set must be learned to access IRC with

a text-based client (there may not be a point-and-click

graphical client available for every operating system)

From the text line, a conversation on IRC is joined

by typing #join gardening (or a topic of interest other

than gardening) It's a good idea to visit the help

chan-nel by typing #join irchelp to get a feel for the way

things work There are thousands of IRC channels,

so most common topics already exist; ifyou are seek-ing an uncommon topic, it will be automatically cre-ated when the command #join myweirdtopic is typed The channel automatically disappears shortly after the last person leaves, except in the case of registered channels, but comes back (is recreated) as soon as it

is re-entered

Most IRC channels are public forums, but private keyword-protected IRC channels can be created at any time Courtesy is very important on IRe Ifa participant is rude, crude, inflammatory, or off-topic,

he or she will be summarily kicked off the channel

by an operator If there is no operator present, usu-ally everyone else will leave Observe courtesy and Netiquette on IRC, and don't talk unless it's some-thing worth saying The operators or "ops" are hard-working volunteers who strive to make the IRC an open and fair forum for all

The IRC software is freely distributable through a GNU General Public License from the Free Software Foundation Many Internet Services Providers pro-vide IRC access Communications are predominantly

in English, but other languages are sometimes used See Internet Relay Chat operator, RFC 1459, RFC 2810, RFC 2811, RFC 2812, RFC 2813 Internet Relay Chat operatorAnindividual desig-nated with certain responsibilities and powers for a channel on Internet Relay Chat (IRC), a public com-munications forum on the Internet.Inan active chat channel, some of the participants are designated with

"@"symbols next to their online nicknames These operators or "ops" have jurisdiction ove( their chan-nels and may set the guidelines for interaction and remove those who do not follow the guidelines Be-cause they establish and maintain law and order on IRC, many people call them IRC cops In general, IRC ops are hard-working volunteers who make rea-sonable decisions and have kept IRC a viable com-munications medium in spite of the many people re-luctant to follow guidelines of good taste and com-mon sense See Internet Relay Chat

Internet Relay Chat (Server) Protocol IRC Server Protocol A protocol for describing how Internet Re-lay Chat (IRC) servers may connect together to form

a network The IRC protocol was first implemented

in the late 1980s and grew to support a worldwide network ofservers and clients in just a few years IRC Protocol is text-based and enables a simple socket program to connect as a client Over the years, vari-ous developers have created operating systems-spe-cific text and graphical clients to interact in IRC chat sessions using IRC Protocol.Ingeneral, IRC Proto-col has been implemented overTCP/IP,though there

is no restriction as to this

Each IRC server has a unique name up to 63 charac-ters and maintains a global state database that gives

a picture of the IRC network so that each server is known by other servers A hostrnask can be used to group servers according to name in order to exclude hosts outside of the list Servers hold netwide unique identifying nicknames (up to 9 characters), user-names, and connecting host informaton for each

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Internet Relay Chat Protocol was submitted as an

Experimental RFC in May 1993 by Oikarinen and

Reed and has been updated by numerous RFCs since

that time See Internet Relay Chat, RFC 1459,

RFC 2810, RFC 2811, RFC 2812, RFC 2813

Internet Research Steering GroupIRSG The IRSG

manages the Internet Research Task Force (IRTF) in

conjunction with the IRTF Chair Membership in

IRSG is primarily those in chairing positions in the

various research groups The IRTF Chair is appointed

by the Internet Architecture Board

Internet Research Task Force!RTF.An

organiza-tion engaged in discussion and Internetworking

re-search to further the evolution of the Internet,

espe-tocols, and applications The IRTF works in consul-tation with the Internet Research Steering Group (IRSG) and with the Internet Engineering Task Force (IETF) and the Internet Architecture Board(lAB). See RFC 2014 http://www.irtf.org/

Internet Resource AccessIRA.AnOEM product distributed by CREN in cooperation with ffiM, an-nounced in August 1994 This system was intended

to facilitate Internet access for global academic and research communications by institutions that had largely been connected by BITNET networks up un-til this time ffiM provided hardware and software

as a foundation for the CREN system IRA provided connectivity between RSCS on IBM systems and

Internet Relay Chat Command Examples

/basics Very basic introductory information about IRC; a good thing to read the

first time you use the system Alsotryout/help newuser

/bye Drops the user out ofIRC; /qui t, / exi t, and / signoff do the same /clear Clears the current window; reduces clutter

/date Displays the current date and time for the local server or a specified

server The /time command performs the same function as the / dat e command

/join <channel> Changes the location to the specified IRC channel For example,

/ join #buglovers puts the user in the channel with other insectophiles

/help <info> Self-explanatory and the command to type if you're really stuck

/info Provides information about the origins of IRC, its creators, maintainers,

slaves, and other perpetrators

/list Provides a very long list of thousands of channels, and information about

the topics and number of participants, so use this command with caution The*(wildcard) character may be used to specify the characteristics of the listing, as can a number of useful arguments: -pub1 i c shows only public channels; -private shows only private channels; -topic shows only channels with a specified topic

/msg <nickname> Sends a single private message to the specified person Use /query if

longer private conversations are desired

/menus A simple scripting feature for creating custom user menus for an IRC

session This is great for creating mnemonic commands or shortcuts

/newuser Information about IRC commands and IRC etiquette

/nick Sets the user's nickname If the nickname is taken, another must be

selected, or the default used

/news Information about changes, updates, new commands, and other

IRC-related functions It's a good idea to check this once in a while

/query <nickname> Initiates a private conversation with a specified user Anything you type

now is seen only by that user The query command with no arguments cancels query mode

/set <variable> Sets various status, logging, and message parameters

/who Lists users on IRC; with a*(wildcard), it shows the local channel A

number of arguments can restrict the listing, e.g., -operators lists only operators

/whois <nickname> Provides more detailed information about the user specified, and his/her

"actual identity."

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Internet TCP/IP on open systems See BITNET,

Corporation for Research and Educational

Network-ing

Internet Safety PolicyISP A policy required to be

in place in federally funded institutions that provide

Internet access to vulnerable individuals, especially

children See Children's Internet Protection Act

Internet SecretariatAnorganization providing

ad-ministrative assistance to a variety of Internet

gov-erning bodies

Internet Security Association and Key

Manage-ment ProtocolISAKMP.Anapplication-level

net-work protocol submitted as a Standards Track RFC

by Maughan et al in November 1998 ISAKMP

uti-lizes security concepts for establishing Security

As-sociations (SAs) and cryptographic keys within the

Internet environment It defines procedures and

packet fonnats for peer authentication, SA creation

and management, key generation, and threat

mitiga-tion for establishing and maintaining secure

commu-nications

ISAKMP is distinct from key exchange protocols, as

there may be various key exchange protocols with

different security properties A common framework

facilitates intercommunication through SA attribute

formats for negotiations, modifications, and deletions

at all layers of the network stack ISAKMP has been

assigned UDP port 500

Cisco Systems provides a no-charge ISKMP software

distribution based upon the IETF ISAKMP to

sup-port Internet Key Management through this protocol

See RFC 2408

Internet Services ProviderISP Acommercial

ven-dor providing access to the Internet and some or all

of its services These services may include email,

newsgroup access, World Wide Web access, Internet

Relay Chat (IRC), temet to other sites, Unix shell

accounts, and more Some providers have flat-rate

fees for unlimited access, while others provide

un-limited access during off-peak hours, and un-limited or

pay access during times of heavy use Others charge

by connect time Many distinguish between

commer-cial and personal users, with separate fee scales for

each, usually with more mailboxes and longer

connect times for business users

The ISP's link to the Internet may be through a vari-ety of connections, usually 56 kbps or higher, up to

TI or even T3 lines However, when dialing up through a regular modem on a phone line, you will not be able to receive and transmit infonnation faster than the slowest point in the link (e.g., the modem speed) There are several large, well-known provid-ers, as well as thousands of small, local service pro-viders The level of service of many small providers equals or exceeds those of the large companies, so shop around See Internet Access Provider, National Service Provider

Internet SocietyISOC A significant nonprofit in-ternational professional organization dedicated to furthering global cooperation and coordination ofthe evolution of the Internet and its associated technolo-gies ISOC was founded in January 1992 It grew out

of standards development activities of the IETF and Internet Activities Board (lAB) in the early 1990s and counts among its members many of the early Inter-net pioneers Fund-raising to continue to support the standards process was one of the important initial mandates of the Society The ISOC oversees and/or works with a number ofother agencies, including the Internet Architecture Board (lAB) and the Internet Engineering Steering Group (IESG) It supports and promotes Internet-related public policy, education, standards, and participation in the Society See RFC 1310, RFC 1602 http://www.isoc.org/ Internet Software ConsortiumISC A group dedi-cated to developing production-level high-quality reference implementations of Internet technologies suitable for use by large-scale network providers and operators Subgoals include compliance to key stan-dards, straightforward implementation, and high interoperability The ISC was fonned with financial assistance from UUNET Communications Services and later from the Internet Multicasting Service and various sponsors http://www.isc.org

Internet Standards processThe orderly evolution ofthe Internet is ofconcern to many networking pro-fessionals, so the Internet community at large has developed various procedures to facilitate this process

Internet Standards Process - Levels of Maturity

Standard Abbr Description

Proposed PS Entry-level for standards-track specifications as accepted by the IESG To become a

PS, a specification must be technically complete, generally well understood, received

by the Internet community, and have design and reliability issues resolved.

Draft DS A PS may be promoted to DS after at least two independent and interoperable

implementations from different code bases have been developed and sufficient successful operational experience has been obtained DS status indicates confidence that the specification is mature and will be useful.

Approved IS A DS may be promoted to IS and assigned an STD series number if significant

implementation and operational maturity are achieved and the IS promises to be of significant benefit to the Internet community.

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Internet standard, it must go through a formal

discus-sion, evaluation, and testing process Aprotocol must

pass through several defined levels of maturity,

in-cluding Proposed Standard, Draft Standard, and

(Internet) Standard and is documented in Requests

for Comments (RFCs) notifications to the Internet

Community

The Internet Engineering Task Force (IETF) must

recommend advancement at each stage for the

pro-tocol to pass to the next level, and specified waiting

periods are imposed Intellectual property rights (e.g.,

patents) must be identified and noted in Standards

Track documents When a protocol has successfully

gone through the successive levels of the Standards

process, it is assigned an STO number The process

is somewhat recursive in that it is described within

itself in RFC 1602

If a standard becomes outdated, the IESG may elect

to retire it and appropriate notifications will be posted

For a standard to be revised, it must go through the

full standards process again The old standard will

usually be superseded and retired to Historic status.

However, if the new standard is sufficiently

differ-ent or more mature than the previous standard such

that both implementations have current

implementa-tion value, the two may coexist

Non-standards-track specifications are labeled as

Experimental, Informational, or Historic

The Best Current Practice (BCP) subseries is a

struc-ture similar to the Internet Standards process within

which proposals from community leaders can be

fielded within the Internet community to stimulate

and enable the development ofguidelines for

consen-sual policies and operations See Internet

Engineer-ing Task Force, RFC 1311, RFC 1602, RFC 2026

Internet TransparencyIn essence, Internet

Trans-parency is a philosophy and design goal that supports

the capability of the Internet to send anything

any-where It holds that packets should be able to carty

any type of data to any desired destination without

the user worrying about format, routing,

interoper-ability or other underlying aspects of an

intercon-nected homogenous network In actual

implementa-tion, there have been fits and starts and the occasional

backslide in holding to this philosophy, but there

ap-pears to be a general desire to continue to work

to-ward this goal and to extend the capabilities and

over-come the technical limitations that stand in the way

of a fully transparent Internet system

In February 2000, B Carpenter submitted an

Infor-mational RFC discussing this issue that was used as

input to an IntemetArchitecture Board (lAB)

work-shop heldinJuly 1999 The RFC documents some

ofthe sources ofloss oftransparency and, in

particu-lar, issues such as firewalls, IP address allocation,

intranet models, etc See RFC 2775

Internetwork Packet Exchange ProtocolIPX A

network layer protocol that provides addressing,

rout-ing, and packet-switching functions for Open

Sys-tems Interconnection (OSI) model sysSys-tems IPX

works on a best-efforts basis to deliver packets

cation ofsuch (these are handled by other protocols)

Internetworking AllianceSee World Internet Alli-ance

Internetworking OverNBMA ION A working group jointly chartered with the Internet and Rout-ing Area ofIETF, ION is a merger of the IPATM and ROLC groups.Itfocuses on issues ofinternetworking network layer protocols over NBMA subnetwork technologies, including encapsulation, multicasting, address resolution, optimization, and others See ATM, Frame Relay, SMDS, X.25, ISSLL, ITU, RFC 1932

InterNICInternet Network Information Center This

is a service mark of the U.S Department of Com-merce; the name was associated for a number ofyears with an authorized central registry for domain names IT:=£~\~~i~~t~e~:i: ::~~::~~s:::t::exclusive provider of domain name registry services::. for Top Level Domains (TLDs) in 1991 InterNIC

was established in 1993 in cooperation with the Na-tional Science Foundation (NSF) to continue domain name registration To be part ofthe Internet, you need

a unique identifier for the network and the individual host from which information is being sent The do-main name is associated with an IP number to create

a unique address on the Internet (More than one do-main name can be assigned to an IP number, depend-ing upon the administrative policies and services of-fered by individual ISPs.) In order to manage this administrative task, InterNIC kept track of registra-tions and domain name-IP number correspondences

in a central database archive

There has been a yearly fee since the mid-1990s for the registration and maintenance of domain names and the monopolistic nature of InterNIC has come under continued dispute, with various stalled propos-als for providing additional domain name extensions and competitive opportunities for other name regis-tries In 1998, VeriSign GRS was separated from Network Solutions, Inc at the time Network Solu-tions Registry was handling domain name registrar services

By the late 1990s, many proposals for additional do-main name extensions had been tendered and other registrars were being approved for granting domain names A central database still needed to be main-tained to ensure uniqueness and an orderly process for registrations, which were now in the tens and hun-dreds of thousands per month (and rapidly increas-ing) The demand for names was largely due to the increase ofusers on the Internet and the commercial-ization of the Net, which resulted in a domain name becoming an important branding and location tool for vendors and other organizations With competition for the provision of domain name registration services, the price dropped from $200 in the mid-1990s to $50

in the late 1990s to $15 (and sometimes less if the domain was bundled with other services) in 2000 By

1999, some commercial firms were reported to be

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applying for as many as 1000 domain names per

month (usually for individual products in their

prod-uct lines) and speculators had registered tens

ofthou-sands of common words and good potential names

in the hopes of reselling them later at a profit A

clamor arose over demand for domain names, with

new registrants claiming that all the good names were

taken The technical difficulties in simply extending

the total number of IP numbers to meet demand are

discussed elsewhere in this reference

The Network Solutions Registry was created and

reg-istry services agreements extended until 2003 The

commonly known established name extensions

in-clude com, edu, gov, net, info, int, usa, and org

(along with assigned extensions for individual

coun-tries) Other extensions were subsequently added in

2001, including biz to satisfy commercial demand

and info for information-based services, with plans

to implement pro, aero, museum, and possibly

oth-ers in the future

VeriSign TRS now provides registry services for the

Internet domains and the InterNIC name is

specifi-cally associated with the Department of Commerce

Web site See domain, domain name, domain name

server, IF address, and the Appendix for a list

ofcoun-try code domain extensions http://interNIC.net/

interprocess communication environmentIPCE

The concept of interprocess communication (IPC)

became important when people began

interconnect-ing computers and developinterconnect-ing protocols to allow

them to share data communications

With the spread of timeshare networks in the late

1960s and 1970s, the various hardware and software

mechanisms to facilitate IPC bepan to develop They

expanded when remote "smart' terminals and

peer-to-peer networks were invented Computer bulletin

board systems (BBSs) and local area networks

(LANs) in the 1980s and the Internet in the 1990s are

important extensions ofthe general concepts ofIPC

They have increasingly enabled users to utilize

re-sources on remote systems and even to share files and

programming environments as though they were

lo-cal resources, thus extending IPC from something

transient and part-time in its earlier implementations

into a system in which many of the computers and

processes are in 24-hour communication with one

another This doesn't just speed up the sharing of

in-formation and resources; it also creates a higher

or-der of environment, somewhat like a cooperative or

symbiotic digital organism Given the advantages of

access to greater resources through a larger, more

so-phisticated interprocess communications system,it

is likely that this trend will continue With high-speed

optical connections, the distinction between

process-ing speeds and bus speeds (that provide

intercommu-nication among systems) becomes less critical and

individual machines in advanced IPCEs may begin

to lose their distinction as individual systems and be

seen more as specialized aspects of a larger

comput-ing environment

interrogate1.Inlower level software, to query the

availability or state ofa device or process 2.Inhigher

level software applications, to query a data or infor-mation resource in a systematic manner For example,

an intelligent agent may query a number of search engines on behalf of a user to find suitable avenues for further inquiry, thus automating and streamlining the process for the user 3 In human terms, to sys-tematically query the availability of specific data or information or to systematically query answers to general or particular questions, as in a database or other information archive

interruptA hardware system computing resource that causes a suspension of a process, usually to per-form another temporary function On some desktop systems, interrupts were implemented as a means of handling device requests to the CPU and were thus assigned IRQ numbers This method has a number

of significant limitations in that interrupts are often limited and must be carefully assigned to conserve resources and prevent conflicts, and no two devices can use the same interrupt simultaneously

On an IRQ-driven system with several peripherals,

it was sometimes necessary to disable one device (e.g., an internal modem) in order to operate another device (e.g., a sound card) This means of managing system resources was not common to all computers, but a significant number ofIntel-based consumer ma-chines sold in the 1980s and early 1990s had this form

of interrupt-handling

To overcome the problem of interrupt-handling, a number of vendors developed a system called Plug and Play, which allowed dynamic allocation ofinter-rupts and power-on swapping of devices or device controller cards, provided that they support the Plug and Play format (Don't just assume a component is Plug and Play; verify it.) While this doesn't fully change the underlying concept,itis at least a solu-tion that aids consumers in getting the best use oftheir machines See IRQ and accompanying Interrupt Re-quest Numbers chart See Plug and Play

INTERSPUTNIK The Russian word for satellite is

sputnik The INTERSPUTNIK International

Organi-zation of Space Communications system ofsatellites delivers a variety ofprogramming and data services, including the Voice of America (VOA), which has formed business relationships with a number of in-dependent Russian radio stations, and Direct Net Telecommunications, which provides international digital voice and data services See INTELSAT Interstate Commerce Act of 1887Anact established

to regulate the growing interstate railroad business, with the intent of ensuring fair and equitable deal-ings between transportation carriers and the public Later, the jurisdiction of the Interstate Commerce Commission was broadened to include regulation of communications services, including telephone, tele-graph, and cable Telecommunications services were later split off into separate communications acts as they grew in prevalence and importance and the In-terstate Commerce Commission is now mainly tasked with regulating railroad lines, express companies, and similar transportation carriers

InterSwitch Message ProtocolISMP Amechanism

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exchanged between network switches to maintain a

dynamic record of the network topology See link

state advertisement, Virtual LAN Link Switch

Pro-tocol

intersymbol interferencelSI lSI is a form of

tem-poral distortion found in many aspects of

telecom-munications transmissions where two or more

sym-bols are being transmitted in the same channel and

overlapping of waveforms can occur or in systems

where distortion is associated with the transmission

of sequentially adjacent symbols It is particularly

prevalent where a lot of information is packed into a

tight physical space or a tight time frame Thus, it

tends to occur in wire and optical networks where

high speeds, distance, and attenuation are factors, in

high-density recording data, and in high-speed

wire-less communications (e.g., digitized voice

commu-nications) Rolloffand distortion at transmission band

edges can increase lSI In optical fiber transmissions,

spreading of the optical beams over distance can

re-sult in increased dispersion and lSI

Various statistical models for detecting this type of

interference have been proposed and research on

miti-gating this type of interference was beginning to be

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