Fiber Optics Illustrated Dictionary generation of the 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 InternetAccess Coalition lAC. 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 Provider lAP. A vendor who pro- vides a connection to the Internet in the form of Frame 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. InternetActivities Board lAB. Established in 1983 to replace the Internet Configuration Control Board, the lAB subsequently came under the umbrella of the Internet Architecture Board. See Internet Architec- ture Board. InternetArchitecture Board lAB. Formerly the In- ternet Activities Board (and before that, the Internet 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/ InternetAssigned Numbers Authority lANA. 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 of unique 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/ 502 InternetChannelCommerce 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 of Environmental Biology's Research Collections in Systematics & Ecology Program through the Mu- seum of Paleontology at Berkeley to facilitate devel- opment of improved 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 Board ICCB. 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 Protocol ICMP. 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 © 2003 by CRC Press LLC classes, as shown in the Classes and Fonnat of ICMPv6 Messages chart. See RFC 792. Internet Corporation for Assigned Names and Numbers ICANN. Anot-for-profit organization es- tablished as aresult of studies and recommendations reported in the White Paper issued by the National Telecommunications and Infonnation Administration (NTIA) of the U.S. Department of Commerce 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 of the 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 Group IESG. 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 of the Internet Society (ISOC) and works within ISOC rules and procedures. See Internet Architecture Board. http://www.ietf.org/iesg.html Internet Engineering Task Force IETF. The IETF is governed by the Internet Engineering Steering Group (IESG). It is a large, international open com- munity of network researchers and designers dedi- cated to the positive evolution of Internet architec- ture and operations. The IETF is the primary Internet protocol develop- ment and standardization body. The IETF has worked long and hard on IP Version 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 ~~:~:~!~~~~r~~~=~~~~J~ifi~ !. Network Information Center (NIC). Internet Fax The terminology and goals for the de- velopment of Internet 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 o to 127 128 to 255 ICMPv6 messages have the following fonnat: 012 3 012345678 9 012 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 901 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ I Type I Code I Checksum I +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ I I + Message Body + I I 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. 503 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary 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 ExpressionAlliance IFEA. 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 Protocol IGMP. 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. InternetInformationInfrastructureArchitecture 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 Committee IAHC. The IAHC was a coalition of members of the Inter- net community cooperating to develop recommenda- tions for the expansion of the 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 Protocol IMP. This is one of the historic Internet protocols, submitted by 1. Postel in March 1979. It describes a means for transmitting messages between message processing modules over interconnected networks. Message processing mod- ules are processes in host 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 of user-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 504 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. InternetMessagingAccess Protocol IMAP. 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. InternetNetworkInformation Center See InterNIC. InterNet News INN. An NNTP/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 of unofficial updates. thereaf- ter, maintenance of INN was taken over by the Inter- net Software Consortium (ISC). See C News, USENET. Internet Official Protocol Standards The title ofa Request for Comments (RFC) document released from time to time to inform the Internet community of the state of standardization of protocols 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 Protocol IOTP. An inter- operable framework for electronic commerce over the Internet optimized for transactions between nonac- quainted parties. IOTP is independent of the payment system and can encapsulate and support secure chan- nel card payment, GeldKarte, Mondex, and others. © 2003 by CRC Press LLC IOTP V. 1.0 was described in an Informational RFC submitted by D. Burdett in April 2000, and was sup- portedby a description ofdigital signatures for IOTP presented by Davidson and Kawatsura. In April 2001, W. Hans et al. submitted an Internet Draft for a Payment Application Programming Inter- face (API) for IOTP. It proposed 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 Phone A 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 oftraditional phone subscribers can be accessed through a phone direc- tory. See Global Online Directory. Internet Policy Registration Authority IPRA. A top-level digital security certification authority (CA) in the Internet certification hierarchy. IPRA is X.509- compliant. InternetPrintingProtocol IPP. An application 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. It is a simplified model, including abstract objects, at- tributes, and operations that are independent of trans- port and encoding methods. Essentially the model is based upon aprinter and ajob object, with ajob op- tionally representing multiple documents. Users can query printer capabilities, submit jobs, get status in- 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 The IPP implementor's guide was submitted as an Informational RFC by Hastings and Mamos in July 1999 to aid imp lementors 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 Protocol IP. 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 ofassociated protocols. Logical IP addresses are used to identify hosts by means of network and node addresses. A number of categories of networks are supported as IP Classes. RFC 768 describes Internet Protocol. RFC 1602 is recommended for its description of the Intemet stan- dards process, and RFC 2200 is a useful standards 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. InternetProtocolConsortium IPC. 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. Of current interest is a test lab for test- ing IPv6 implementations, the version of Intemet Pro- tocol being phased in to coexist with and probably eventually supersede IPv4. Internet Protocol (IP) Mobility Support A 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 of where 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 of address 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 Suite IPS. Astandardized set of protocols based on a layered model that enables In- ternet systems to intercommunicate. Minimally, a 505 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary 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 ofother 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 apoint-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 ofinterest 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, 506 so most common topics already exist; if you 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. If a 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. InternetRelay ChatoperatorAn individual desig- nated with certain responsibilities and powers for a channel on Internet Relay Chat (IRC), a public com- munications forum on the Internet. In an 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. InternetRelay Chat(Server) Protocol IRC Server Protocol. Aprotocol 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 of servers 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. In general, IRC Proto- col has been implemented over TCP/IP, though there is no restriction as to this. Each IRC server has aunique 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 © 2003 by CRC Press LLC client currently connected to the IRC system. 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 Group IRSG. 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- cially with respect to technologies, architecture, pro- tocols, and applications. The IRTF works in consul- tation with the Internet Research Steering Group (IRS G) and with the Internet Engineering Task Force (IETF) and the Internet Architecture Board (lAB). See RFC 2014. http://www.irtf.org/ Internet Resource Access IRA. An OEM 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 connectedby 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 Command Description /basics Very basic introductory information about IRC; a good thing to read the first time you use the system. Also try out /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 / da t 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 ofparticipants, so use this command with caution. The * (wildcard) character may be used to specify the characteristics of the listing, as can a number ofuseful arguments: - pub 1i 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., - opera tors lists only operators. /whois <nickname> Provides more detailed information about the user specified, and his/her "actual identity." 507 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary Internet TCP/IP on open systems. See BITNET, Corporation for Research and Educational Network- ing. Internet Safety Policy ISP. 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 SecretariatAn organization providing ad- ministrative assistance to a variety of Internet gov- erning bodies. Internet Security Association and Key Manage- ment Protocol ISAKMP. An application-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. InternetServices Provider ISP. A commercial 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 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 Society ISOC. A significant nonprofit in- ternational professional organization dedicated to furthering global cooperation and coordination of the 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 of other 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 Consortium ISC. 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 process The orderly evolution of the Internet is of concern 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. 508 © 2003 by CRC Press LLC F or a technology to become an official or required Internet standard, it must go through a formal discus- sion, evaluation, and testing process. A protocol 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. Ifa standard becomes outdated, the IESG may elect to retire it and appropriate notifications will be posted. F or 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 of guidelines for consen- sual policies and operations. See Internet Engineer- ing Task Force, RFC 1311, RFC 1602, RFC 2026. Internet Transparency In 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 ofa 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 held in July 1999. The RFC documents some of the sources of loss of transparency and, in particu- lar, issues such as firewalls, IP address allocation, intranet models, etc. See RFC 2775. Internetwork Packet Exchange Protocol IPX. A network layer protocol that provides addressing, rout- ing, and packet-switching functions for Open Sys- tems Interconnection (OSI) model systems. IPX works on a best-efforts basis to deliver packets without a guarantee of successful delivery or verifi- cation of such (these are handled by other protocols). InternetworkingAlliance See World Internet Alli- ance. Internetworking Over NBMA ION. A working group jointly chartered with the Internet and Rout- ing Area ofIETF, ION is a merger of the IPATM and ROLC groups. It focuses on issues of internetworking 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. InterNIC Internet Network Information Center. This is a service mark of the U.S. Department of Com- merce; the name was associated for a number of years 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 of the 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 of users 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 509 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary applying for as many as 1000 domain names per month (usually for individual products in their prod- uct lines) and speculators had registered tens of thou- 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 of coun- try code domain extensions. http://interNIC.net/ interprocess communication environment IPCE. The concept of interprocess communication (IPC) became important when people began interconnect- ing computers and developing 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 of the 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 ofa larger comput- ing environment. interrogate 1. In lower level software, to query the availability or state ofa device or process. 2. In higher 510 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 behalfofa 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. interrupt A hardware system computing resource that causes a suspension ofa 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 of Intel-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 of inter- 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, it is at least a solu- tion that aids consumers in getting the best use of their 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 of satellites delivers avariety of programming 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. InterstateCommerceAct of 1887 An act 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 Protocol ISMP. A mechanism © 2003 by CRC Press LLC for encapsulating and transmitting control messages exchanged between network switches to maintain a dynamic record of the network topology. See link state advertisement, Virtual LAN Link Switch Pro- tocol. intersymbol interference lSI. 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). Rolloff and 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 ofinterference was beginning to be more comprehensively documented in the mid- 1990s. Precoding (often in conjunction with Trellis coding) can sometimes help reduce lSI. Sometimes lSI is deliberately introduced into a transmission to shape the signal and may be systematically removed at the receiving end to mitigate other types of trans- mission problems. intra-A prefIX for inside, within. An intranetwork is a network within a company, home, or other confined locality. In many business contexts, it implies an In- ternet-compatible internal network, with many of the same functions, such as a Web server, IRC server, email server, etc. intracellular electrodeA device created in 1949 by Ling and Gerard. It consisted ofa tiny glass capil- lary tube with conducting salt, no more than a few tenths ofa micron in size. When used in a microprobe, it was possible to measure electrical currents in indi- vidual biological neurons. See neural networks. intranetAn internal network, as in a company or in- stitutionallocal area network (LAN). The term was coined in part to distringuish internal networks from inter-business networks ( extranets). Actually, the first meaning ascribed to intranets was inter-business net- works, but even the person who coined the term gradually abandoned it in favor of the de facto LAN connotation. See extranet. intrapreneurA person within an organization, usu- ally a large one, who manages, takes risks, proposes and promotes ideas, leads, and generally behaves as an entrepreneur within and on behalf of the organi- zation. See entrepreneur. intruder An entity attempting to gain access or gain- ing access to a restricted system or system resource without proper authorization. See hacker. intrusion detection The process of determining whether an intruder is attempting to gain access or has gained access to a system or resource without proper authorization. This can apply to physical en- vironments, where various motion detectors and other technologies may detect the presence of an object or person that should not be present, as well as virtual environments, where an unauthorized process or anomalous process or unusual pattern of activities may indicate unauthorized activities. System moni- tors, intrusion detection algorithms, usage patterns, incorrect password limits, and electronic alarms are all mechanisms used in network intrusion detection. inverse multiplexerA multiplexer is a device which takes a circuit, broadcast signal, or given amount of data bandwidth and breaks it up into smaller seg- ments. An inverse multiplexer does the opposite: it takes a number of smaller segments and puts them together to create a larger entity. An inverse multiplexer is often used in conjunction with computers for high bandwidth applications to coordinate the signals, as in videoconferencing sys- tems that require more than one data line to operate. As an example, imagine an ISDN data network set up for videoconferencing. Videoconferencing re- quires fast transmission ofhigh-bandwidth resources: video and sound. Some videoconferencing systems are designed to run over two or three separate ISDN lines. In this case, the inverse multiplexer takes the data from the three sources, coordinates the timing, and sends this information to the computer system, which then displays the images and plays the sound together. inverter 1. A device or circuit which reverses the polarity ofa signal (from positive to negative, or vice versa). 2. A device which changes AC to DC or vice versa. AC to DC inverters (often called converters) are very commonly used in digital electronics that draw AC power from a socket. 3. A device or opera- tion that inverts a signal. If the incoming signal is high, the inverted, outgoing signal is low, and vice versa. It is sometimes called a NOT circuit. Inward Operator Personnel who can assist other operators (e.g., TSPS operators) in making call con- nections. Nonnally an Inward Operator does not com- municate directly with callers, though phone phreakers have been known to do so. InWATS Inward Wide Area Telephone Services. A subscriber service to receive incoming calls and be billed for them, rather than having the caller billed, somewhat like an automated collect call. This service is provided by a variety of local and interexchange carriers. See OutWATS, WATS. IOC See ISDN Ordering Code. IOL InterOperability Lab. Research, development, and vendor verification ofinteroperability of wire- less communications products at the University of New Hampshire. ION See Internetworking Over NBMA. ionization 1. The process of dissociating atoms or molecules into ions and/or electrons. See scintillation. 2. The process of rendering a gas to be conducting by causing some of the electrons to detach from its molecules. 3. The process of rendering a solution to 511 © 2003 by CRC Press LLC . 2 3 4 5 6 7 8 901 +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ -+ I Type I Code I Checksum I +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ - +-+ -+ I I + Message Body + I. LLC Fiber Optics Illustrated Dictionary applying for as many as 1000 domain names per month (usually for individual products in their prod- uct lines) and speculators had registered tens of thou- sands of common words and good potential names in the hopes of. Suite IPS. Astandardized set of protocols based on a layered model that enables In- ternet systems to intercommunicate. Minimally, a 505 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary 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