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X. Glossary of Terms.

     TCP/IP introduces a wide range of terms that most computer users are
not used to, here is a small list to assist in making some sense out of
Internet.  And  hopefully the documentation that comes with TCP/IP
packages.


address  - There are two separate uses of this term in internet  networking:   
     "electronic mail address" and "internet address".   An electronic mail 
     address is the string of characters that you must give an electronic mail
     program to direct a message to a particular person. See "internet     
     address" for its definition.   


ANSI  -   American National Standards Institute  A group that certifies     
     organizations which develop U.S. standards for the information        
     processing industry.  ANSI  accredited groups participate in defining   
     network protocol standards.   


ARP -    Address Resolution Protocol  An Internet protocol which runs on 
     Ethernet and all IEEE 802.X LANs which maps internet addresses to MAC
     addresses.   


ARPANET - Advanced Research Projects Agency Network  A pioneering long         
     haul network funded by ARPA.  It served as the basis for early networking 
     research as well as a central backbone during the development of          
     the Internet.  The ARPANET consisted of individual packet  switching      
     computers interconnected by leased lines. 

 

 AS -   Autonomous System  A collection of gateways (routers) under a single 
     administrative authority using a common Interior Gateway Protocol for   
     routing packets.


ASCII -  American (National) Standard Code for Information Interchange


B  -  Byte  One character of information, usually eight bits wide.  


b  -  bit - binary digit  The smallest amount of information which may be 
     stored in a computer.  


BITNET - Because It's Time Network  BITNET has about 2,500 host computers,    
     primarily at universities, in many countries.  It is managed by           
     EDUCOM, which provides administrative support and information             
     services.  There are three main constituents of the network: BITNET 
     in the United States and Mexico, NETNORTH in Canada, and EARN 
     in Europe.  There are also AsiaNet, in Japan, and connections in 
     South America.  See CREN.  


 bps  -  bits per second   A measure of data transmission speed.  


BSD  -  Berkeley Software Distribution Term used when describing different
     versions of the Berkeley UNIX software, as in "4.3BSD UNIX".  


catenet - A network in which hosts are connected to networks with varying      
 
     characteristics, and the networks are interconnected by gateways  
     (routers).  The Internet is an example of a catenet.   


CCITT  - International Telegraph and Telephone Consultative Committee   


core gateway  - Historically, one of a set of gateways (routers)  operated by 
     the Internet Network Operations Center  at BBN.  The core gateway system 
     forms a central part  of Internet routing in that all groups had to 
     advertise paths to their networks from a core gateway.  


CREN - The Corporation for Research and Educational Networking   BITNET and    
     CSNET have  merged to form CREN.   


CSNET  - Computer + Science Network  A large data communications network       
     for institutions doing  research in computer science.   It uses several  
     different  protocols including some of its own.  CSNET sites include 
     universities, research laboratories, and commercial  companies.  See      
     CREN.


DARPA   U.S. Department of Defense Advanced Research Projects Agency           
     The government agency that funded the ARPANET and later started the       
     Internet.   


Datagram  - A self-contained, independent entity of data carrying sufficient  
     information to be routed from the source to the destination data terminal 
     equipment without  reliance on earlier exchanges between this source     
     and destination data terminal equipment and the transporting network.
     

default route -  A routing table entry which is used to direct any data 
     addressed to any network numbers not explicitly listed in the routing 
     table.  


DNS - The Domain Name System is a mechanism used in  the Internet for          
     translating names of host computers into addresses.  The DNS also         
     allows host computers not directly on the Internet to have registered 
     names in the same style, but returns the electronic mail gateway which 
     accesses the non-Internet network instead of an IP address.   

 

dot address (dotted address notation) - Dot address refers to the common     
     notation for Internet  addresses of the form A.B.C.D; where each letter
     represents, in decimal, one byte of the four byte IP address.  


Dynamic Adaptive Routing   - Automatic rerouting of traffic based on a sensing
     and analysis  of current actual network conditions.  NOTE: this does not 
     include cases of routing decisions taken on predefined information.


EBCDIC - Extended Binary-coded Decimal Interchange Code


EGP - Exterior Gateway Protocol  A protocol which distributes routing 
     information  to the gateways (routers) which connect autonomous systems.  
 


Ethernet  - A network standard for the hardware and data link levels. There are
     two types of Ethernet: Digital/Intel/Xerox (DIX)  and IEEE 802.3.   


FDDI  - Fiber Distributed Data Interface  FDDI is a high-speed (100Mb) token 
     ring LAN.


FIPS  -  Federal Information Processing Standard  


FSP -  FSP is an "UDP-based FTP", and is a lot like his TCP-based brother.

 

FTP -  File Transfer Protocol  The Internet standard high-level protocol for 
     transferring files from one computer to another.   


gateway - See router   


GB  - Gigabyte  A unit of data storage size which represents 10^9 (one billion)
      characters of information.   


Gb - Gigabit  10^9 bits of information (usually used to express a data transfer
 
     rate; as in, 1 gigabit/second = 1Gbps).
  

GNU - Gnu's Not UNIX   A UNIX-compatible operating system developed by the
     Free Software Foundation.   


header -  The portion of a packet, preceding the actual data, containing source
     and destination addresses and error-checking fields.   


host number  - The part of an internet address that designates which node on 
     the (sub)network is being addressed.


ICMP -  Internet Control Message Protocol   ICMP is an extension to the 
     Internet Protocol.  It  allows for the generation of error messages, 
     test packets and informational messages related to IP.
  

IEEE  - Institute for Electrical and Electronics Engineers


IETF  - Internet Engineering Task Force  The IETF is a large open community of
     network designers,  operators, vendors, and researchers whose purpose  
     is to coordinate the operation, management and evolution of the Internet,
     and to resolve short- and mid-range protocol and architectural issues.  It
 
     is a major source of proposed protocol standards which are submitted to 
     the Internet Activities Board for final approval. 

 
internet   internetwork   -  Any connection of two or more local or wide-area 
     networks.


Internet  - The global collection of interconnected local, mid-level and  
     wide-area networks which use IP as the network layer  protocol.   


internet address  -  An assigned number which identifies a host in an internet.
     It has two or three parts: network number, optional subnet number, and 
     host number.


IP - Internet Protocol   The network layer protocol for the Internet.  It is a 
     packet switching, datagram protocol defined in RFC 791.  


ISO - International Organization for Standardization   


KB - Kilobyte  A unit of data storage size which represents 10^3 (one thousand)
     characters of information. 
 

Kb  - Kilobit   10^3 bits of information (usually used to express a data 
     transfer rate; as in, 1 kilobit/second = 1Kbps = 1Kb).


LAN -  Local Area Network   A network that takes advantage of the proximity of
     computers  to offer relatively efficient, higher speed communications
     than long-haul or wide-area networks. 


MAC  - Medium Access Control   For broadcast networks, it is the method which 
     devices use to determine which device has line access at any given time. 


MAN -  Metropolitan Area Network 


MB -  Megabyte  A unit of data storage size which represents 10^6 (one million)
     characters of information.  


Mb  -  Megabit   10^6 bits of information (usually used to express a data 
     transfer rate; as in, 1 megabit/second = 1Mbps).  


NBS  - National Bureau of Standards   Now called NIST. 

  
network number   -  The part of an internet address which designates the 
     network to which the addressed node belongs.   


NFS - Network File System   A network service that lets a program running on
     one computer to use data stored on a different computer on  the same      
     internet as if it were on its own disk.


NIC  - Network Information Center   An organization which provides network
     users with information about services provided by the network.


NOC  - Network Operations Center  An organization that is responsible for      
     maintaining  a network.  


NIST  -  National Institute of Standards and Technology    Formerly NBS.


NSFNET  - National Science Foundation Network  The NSFNET is a highspeed       
 
     "network of networks" which is  hierarchical in nature.  At the highest 
     level is a  backbone network currently comprising 16 nodes connected to a
     45Mbps facility which spans the continental United States.  Attached to
     that are mid-level networks and  attached to the mid-levels are campus 
     and local networks.  NSFNET also has connections out of the U.S.  to      
     Canada, Mexico, Europe, and the Pacific Rim.  The  NSFNET is part of the 
     Internet.   


NSFNET  -  Mid-level Level Network  A network connected to the highest level of
     the NSFNET that  covers a region of the United States.  It is to mid-level
     networks that local sites connect.  The mid-level networks were once      
     called "regionals".   


OSI -  Open Systems Interconnection   A set of protocols designed to be an
     international standard method for connecting unlike computers and         
     networks.  Europe has done most of the work developing OSI and will       
     probably use it as soon as possible.   


OSPF  - Open Shortest-Path First Interior Gateway Protocol   A proposed        
     replacement for RIP.  It addresses some problems of RIP and is based      
     upon principles that have  been well-tested in non-internet protocols. 
     Originally  acronymed as OSPFIGP.   


packet  - The unit of data sent across a packet switching network. The term is
     used loosely. While some Internet literature uses it to refer specifically
     to data sent across a physical network, other literature views the 
     Internet as a packet switching network and describes IP datagrams as 
     packets.  


PC - Personal Computer  


PCNFS  - Personal Computer Network File System   


PPP  -   Point-to-Point Protocol   The Point-to-Point Protocol (PPP) provides 
     method for  transmitting datagrams over serial point-to-point links.  


protocol  -  A formal description of message formats and the rules two 
     computers must follow to exchange those messages. Protocols can 
     describe low-level details of  machine-to-machine interfaces (e.g., the 
     order in which bits and bytes are sent across a wire)  or high-level 
     exchanges between allocation programs (e.g., the way in which two programs
     transfer a file across the Internet).


RFC  -  The Internet's Request for Comments documents series   The RFCs are
     working notes of the Internet research and  development community.  A 
     document in this series may be on essentially any topic related to     
     computer communication, and may be anything from a meeting report to      
     the specification of  a standard.


RIP   -  Routing Information Protocol    One protocol which may be used on     
     internets simply to pass  routing information between gateways. It is used
     on many LANs and on some of the NSFNET intermediate level networks.   


RJE  -   Remote Job Entry   The general protocol for submitting batch jobs and
     retrieving the results.   


router  -  A special-purpose dedicated computer that attaches to  two or more
     networks and routes packets from one network to the other. In particular,
     an Internet  router forwards IP datagrams among the networks it connects. 
     Gateways route packets to other gateways until they can be delivered to 
     the final destination directly across one physical network.   


RPC  - Remote Procedure Call    An easy and popular paradigm for implementing
     the client-server model of distributed computing.   


server  -  A computer that shares its resources, such as printers and files, 
     with other computers on the network.  An  example of this is a Network 
     Files System (NFS) Server which shares its disk space with one or more
     workstations that may not have local disk drives of  their own.


SLIP  -  Serial Line Internet Protocol   SLIP is currently a defacto standard,
     commonly used for point-to-point serial connections running TCP/IP.  It is
     not an Internet standard but is defined in RFC 1055.   


SMTP  - Simple Mail Transfer Protocol   The Internet standard protocol for
     transferring  electronic mail messages from one computer to another.
     SMTP specifies how two mail systems interact and the format of control
     messages they exchange to transfer mail.


SNA  -  System Network Architecture   IBM's data communications protocol.   


SNMP   - Simple Network Management Protocol   The Simple Network               
     Management Protocol (RFC 1157) is the Internet's standard for remote      
     monitoring and management of hosts, routers and other nodes and       
     devices on a network.


subnet  -  A portion of a network, which may be a physically independent
     network, which shares a network address with other portions of the        
     network and is distinguished by a subnet number.  A  subnet is to a       
     network what a network is to an internet. 


subnet number  -  A part of the internet address which designates a subnet.    
     It is ignored for the purposes internet routing, but is used for intranet
     routing.   


T1 -   A term for a digital carrier facility used to transmit a DS-1 formatted 
     digital signal at 1.544 megabits per second. 


T3 -   A term for a digital carrier facility used to transmit a DS-3 formatted 
     digital signal at 44.746 megabits per second.  


TCP  -   Transmission Control Protocol   A transport layer protocol for the 
     Internet. It is a  connection oriented, stream protocol defined by RFC 
     793.   


TCP/IP -  Transmission Control Protocol/Internet Protocol  This is a common  
     shorthand which refers to the suite of application and transport protocols
     which run over IP.  These include FTP, TELNET, SMTP, and UDP (a       
     transport  layer protocol).   


Telenet  - A public packet-switching network operated by US Sprint.  Also known
     as "SprintNet".   


TELNET -  The Internet standard protocol for remote terminal connection service.
     TELNET allows a user at one site  to interact with a remote timesharing 
     system at  another site as if the user's terminal was connected directly 
     to the remote computer.   


Token Ring - A type of LAN.   Examples are IEEE 802.5, ProNET-10/80 and FDDI.  
     The term "token ring" is often used to denote 802.5  


Tymnet  - A public character-switching/packet-switching network operated by   
     British Telecom.   


UDP  - User Datagram Protocol  A transport layer protocol for the Internet.  It
     is a datagram protocol which adds a level of reliability and multiplexing
     to IP datagrams.  It is defined in RFC 768.


UNIX    An operating system developed by Bell Laboratories that  supports      
     multiuser and multitasking operations.  
 

UUCP  -  UNIX-to-UNIX Copy Program   A protocol used for communication         
     between consenting  UNIX systems.  
  

WAN  -   Wide Area Network   


WHOIS  -  An Internet program which allows users to query a database of
     people and other Internet entities, such as domains, networks, and hosts,
     kept at the DDN NIC.  The information for  people shows a person's        
     company name, address, phone number  and email address.  
 

XNS  -  Xerox Network System   A data communications protocol suite developed 
     by Xerox.  It  uses Ethernet to move the data between computers.   


X.25  -   A data communications interface specification developed to  describe
     how data passes into and out of public data communications networks.      
     The public networks such as Sprintnet and Tymnet use X.25 to interface to 
     customer computers.