administrator - The systems person in charge of a computer. On a RedRak, an administrator is also a special category of user with more system permissions than non-administrator users. There are three levels of users on RedRak: network administrators, who have full access to the RedRak and see the full home menu, local administrators who have full access to all non-network controls (they won't see the Network heading on the home menu, for example) and non-administrator users, who see only the functions available under the "Personal" menu heading.
alias - RedRak uses two types of aliases: network device aliases and email aliases. A network device alias provides your network device with more than one hostname at the same Internet address. Alternative hostnames are specified in Home|Network|Machines|Aliases. Hostname aliases often indicate that the host with that alias provides a particular network service such as archie, finger, FTP, or World-Wide Web. The assignment of services to computers can then be changed simply by moving an alias (e.g. www.doc.ic.ac.uk) from one Internet address to another, without the clients needing to be aware of the change. For example, this network device could be called mail.domainname.com, news.domainname.com, etc. The second kind of alias is an email alias, which allows you to redirect email from a unique alias (an alias that is not a current user, user alias, or news alias) to one or more email accounts. For example, mail sent to administrator could be redirected to your email address. Email aliases can be added or deleted on the RedRak.
Appleshare - An Appleshare server is a dedicated Macintosh that all users on a network share. It is used primarily as data storage and a printer server device for workgroups.
AppleTalk - A proprietary local area network protocol developed by Apple Computer, Inc. for communication between Apple products (e.g. Macintosh) and other computers. This protocol is independent of the network layer on which it runs. See "zone."
application - A complete, self-contained program that performs a specific function directly for the user.
backup (Sometimes "back up" when used as a verb) - A spare copy of a file, file system or other resource for use in the event of failure or loss of the original. The term is most commonly used to refer to a copy of all the files on a computer's disks which is made periodically and kept on removable medium. This essential precaution is neglected by most new computer users until the first time they experience a disk crash or accidentally delete the only copy of the file they have been working on for the last six months. Ideally, the backup copies should be kept at a different site or in a fireproof safe.
BSD LPR printing protocol - BSD is for Berkeley System Distribution, a family of Unix versions. LPR is the Unix Line PRinter print command. This does not actually print files but rather copies (or links) them to a spool area, then a daemon copies them from the spool area to the printer. See "daemon."
catalog - This is the RedRak list of backed up files. One catalog is created for each machine included in the backup. The catalogs are stored on the RedRak for a limited period of time and then are deleted. However, deleted catalogs can be recreated (by using the recatalog function in Home|Services|Backup).
client - A computer system or process that requests a service of another computer system or process (a "server") using some kind of protocol and that accepts the server's responses. A client is part of a client-server software architecture.
commit - In the RedRak, clicking the COMMIT button implements a batch of RedRak changes. A user adds to that queue of changes to be made each time he or she clicks the STORE button.
cookies - A packet of information sent by an HTTP server to a World Wide Web browser and then sent back by the browser each time it accesses that server. Cookies can contain any arbitrary information the server chooses. Typically this is used to authenticate or identify a registered user of a web site without requiring them to sign in again every time they access that site. Cookies are required because a server cannot keep records of who has visited it - that record is maintained by a user's browser and then transmitted back to the server. RedRak requires that your browser be enabled to accept cookies - otherwise, logon will always fail.
daemon - A program that is not invoked explicitly, but lies dormant waiting for some condition(s) to occur.
device - In RedRak, valid devices include a floppy drive, CD-ROM, or hard disk.
DHCP (Dynamic Host Control Protocol) - This protocol provides a means to dynamically allocate IP addresses to computers running on a local area network. The system administrator assigns a range of IP addresses to DHCP and each client computer on the LAN has its TCP/IP software configured to request an IP address from the DHCP server. The request and grant process uses a lease concept with a controllable time period. See "Dynamic Host Control Protocol Servers" in the online help.
DNS (domain name server) - A domain name server is a computer program that maintains a table for translating host names (such as frontdesk.localdomain.com) to IP addresses (such as 192.168.3.37) and IP addresses to host names. Anytime a person sends an email or surfs the web, this translation is needed. The RedRak can perform this function.
domain name - A domain name is the character string name given to a computer network. The domain name gives the machine its identity to the outside world - the world outside your own network. Think of the domain name as your machine's last name. (The host name followed by a dot and the domain name are called the fully-qualified domain name.) You should have already received a domain name from your ISP or InterNIC. It typically has one of the standard Internet suffixes such as ".EDU", ".ORG", ".GOV", ".COM", ".NET" or ".<country>." Domain names are case insensitive so ".EDU" is the same as ".edu". Some examples are "cybernet.com", openskies.net, "darpa.mil", or "umich.edu".
domain - On the Internet, "domain" is most commonly used to refer to a group of computers whose hostnames share a common suffix: the domain name.
download - To transfer data from one computer to another. Downloading (as opposed to uploading) usually refers to transfer from a larger "host" system (especially a server or mainframe) to a smaller "client" system, especially a microcomputer or specialized peripheral.
Ethernet - This is the most widely-installed local area network (LAN) technology. Now specified in a standard, IEEE 802.3, Ethernet was originally developed by Xerox and then developed further by Xerox, DEC, and Intel. An Ethernet LAN typically uses coaxial cable or special grades of twisted pair wires. The most commonly installed Ethernet systems are called 10BASE-T and provide transmission speeds up to 10 Mbps. Devices are connected to the cable and compete for access using a Carrier Sense Multiple Access with Collision Detection (CSMA/CD) protocol. Fast Ethernet or 100BASE-T10 provides transmission speeds up to 100 megabits per second and is typically used for LAN backbone systems, supporting workstations with 10BASE-T cards. Gigabit Ethernet provides an even higher level of backbone support at 1000 megabits per second (1 gigabit or 1 billion bits per second).
FAT (File Allocation Table) Partition - This is a classic file system that is used by MS-DOS and continues to be used by other Microsoft operating systems like Windows 95, Windows 98, and Windows NT 4.0. FAT partitions are specified as a type to be created when they are set up by a utility called fdisk. The RedRak "Run from CD-ROM" mode requires a FAT partition on the PC in order to run.
Firewall - A firewall restricts the traffic into and out of your network. A firewall is the implementation of your security policy. It will allow only that traffic that meets the conditions set by the firewall rules. It is usually installed at the connection between your local network and the Internet.
fully qualified domain name (FQDN) - The full name of a system, consisting of its local hostname and its domain name. For example, "venera" is a hostname and "venera.isi.edu" is an FQDN. A FQDN should be sufficient to determine a unique Internet address for any host on the Internet.
format - Hard disks and other storage devices are said to be formatted when their space has been organized and divided into pieces that can be controlled for convenient storage and access. For example, a hard disk may be formatted into areas called sectors, tracks, and clusters. See "reformat."
FTP (File Transfer Protocol) - A client-server protocol which allows a user on one computer to transfer files to and from another computer over a TCP/IP network. FTP is also the client program the user executes to transfer files.
group - In RedRak, you can apply common characteristics to a collection (grouping) of users, machines, or newsgroups.
host - A computer connected to a network.
hostname - The unique name by which a computer is known on a network, or identified in electronic mail, Usenet news, or other forms of electronic information interchange. On the Internet the hostname is an ASCII string, e.g. "wombat.doc.ic.ac.uk", which consists of a local part (wombat) and a domain name (doc.ic.ac.uk). The hostname is translated into an Internet address by the Domain Name System (DNS). It is possible for one computer to have several hostnames (aliases), though one is designated as its canonical name.
HTML (HyperText Markup Language) - A Hypertext document format used on the World Wide Web.
HTTP (HyperText Transfer Protocol) - The client-server TCP/IP protocol used on the World Wide Web for the exchange of HTML documents.
icon - A small picture intended to represent something (a file, directory or action) in a graphical user interface. When you click an icon, an action such as opening a folder is performed.
IMAP (Internet Message Access Protocol) mail server - A protocol allowing a client to access and manipulate electronic mail messages on a server. It permits manipulation of remote message folders (mailboxes), in a way that is functionally equivalent to local mailboxes. IMAP includes operations for creating, deleting, and renaming mailboxes; checking for new messages; permanently removing messages; searching; and selective fetching of message attributes, texts, and portions thereof. It does not specify a means of posting mail; this function is handled by a mail transfer protocol such as SMTP. See "POP," and "Setting up the RedRak as an IMAP and/or POP Mail Server" under "Mail Servers" under "RedRak Services" in the online help.
Internet - A set of networks all over the world interconnected with routers. The Internet was started by the U.S. Government in 1969 as a network that would continue to function even if a large portion of it were destroyed. The Internet is now a public, cooperative, and self-sustaining facility accessible to tens of millions of people worldwide. Technically, what distinguishes the Internet is its use of a set of protocols called TCP/IP (Transmission Control Protocol/Internet Protocol). For many Internet users, electronic mail (email) has practically replaced paper mailPlace both the RedRak CD-ROM and boot floppy in the PC that will be the RedRak server. for short written transactions. The most widely used part of the Internet is the World Wide Web (often abbreviated "WWW" or called "the Web"). Its outstanding feature is Hypertext, a method of instant cross-referencing.
InterNIC (Internet Network Information Center) - The InterNIC provides domain name registration services. For more information write Info@is.internic.net or visit http://www.interNIC.net.
intranet - Any network, which provides internal services within the network, that are similar to the types of services provided externally by the Internet. Intranet networks need not be connected to the Internet. The most common example of an intranet is the company use of one or more World Wide Web servers on an internal TCP/IP network for distribution of information within the company.
IP (Internet Protocol) - The network layer for the TCP/IP protocol suite widely used on Ethernet networks. It is a scheme that enables information to be rerouted from one network to another, as necessary. Technically, IP is a connectionless, best-effort packet switching protocol.
IP address (also called internet address, TCP/IP address) - The 32-bit host address defined by Internet Protocol that is usually represented in dotted decimal notation, e.g. 192.168.47.216.
ISP (Internet Service Provider) - A company which provides other companies or individuals with access to or presence on the Internet. Most ISPs are also Internet Access Providers; extra services include help with design, creation and administration of World Wide Web sites, training, and administration of intranets.
kiosk - A stall set up in a public place where one can obtain information, e.g. tourist information. The information may be provided by a human or by a computer. In the latter case, the data may be stored locally (e.g. on CD-ROM) or accessed via a network using some kind of distributed information retrieval system such as Gopher or World Wide Web.
LDAP (Lightweight Directory Access Protocol) - A protocol for accessing online directory services. LDAP defines a relatively simple protocol for updating and searching directories running over TCP/IP. LDAP is gaining support from vendors such as Netscape, Novell, Sun, HP, IBM/Lotus, SGI, AT&T, and Banyan. An LDAP directory entry is a collection of attributes with a name, called a distinguished name (DN). Each of the entry's attributes has a type and one or more values. The types are typically mnemonic strings, like "cn" for common name, or "mail" for e-mail address.
LAN (Local Area Network) - A data communications network which is geographically limited (typically to a 1 km radius) allowing easy interconnection of terminals, microprocessors and computers within adjacent buildings. Ethernet and FDDI are examples of standard LANs. Because the network is known to cover only a small area, optimizations can be made in the network signal protocols that permit data rates up to 100Mb/s.
log on - To start a session with a system, usually by giving a user name and password as a means of user authentication. The term, when used as a noun, describes the combination of a user name and password (also called an account), e.g. "Have you been given a logon yet?"
MAC address - The Ethernet card's unique hardware address. This does not have anything to do with Macintosh computers - it stands for Media Access Control. It is the Ethernet card's unique hardware address and is written as twelve hexadecimal (base-16) digits. Each digit is 0-9 or A-F. An example is 0060B039DD24. In the RedRak, the MAC address is optional in order to add a device to the network, but may be required by the DHCP Server. A printer's MAC address can usually be determined by printing out its test or configuration page.
machine - Common term for "computer," usually when considered at the hardware level. In RedRak, printers are also considered a "machine."
netmask - The netmask is usually provided by your ISP. The netmask is a numerical way of specifying the range of IP addresses on your network. For example, all Class C networks have a range of 254 IP addresses and use the Netmask 255.255.255.0.
network - Hardware and software data communication systems. In information technology, a network is a series of points or nodes interconnected by communication paths. Networks can interconnect with other networks and contain subnetworks. The most common topologies or general configurations of networks include the bus, star, and ring topologies. Networks can also be characterized in terms of spatial distance as local area networks (LANs), metropolitan area networks (MANs), and wide area networks (WANs). A given network can also be characterized by the type of data transmission technology in use on it (for example, a TCP/IP or SNA network); by whether it carries voice, data, or both kinds of signals; by who can use the network (public or private); by the usual nature of its connections (dial-up or switched, dedicated or nonswitched, or virtual connections); and by the types of physical links (for example, optical fiber, coaxial cable, and copper wire). Large telephone networks and networks using their infrastructure (such as the Internet) have sharing and exchange arrangements with other companies so that larger networks are created.
network devices - Any computer, printer or router on the network with its own IP address.
news group - One of Usenet's huge collection of topic groups or fora. Usenet groups can be "unmoderated" (anyone can post) or "moderated" (submissions are automatically directed to a moderator, who edits or filters and then posts the results). Among the best-known are comp.lang.c (the C-language forum), comp.arch (on computer architectures), comp.unix.wizards (for Unix wizards), rec.arts.sf-lovers (for science-fiction fans), and talk.politics.misc (miscellaneous political discussions and flamage).
packet - The unit of data sent across a network.
package - A collection of files which (usually) comprise an application, although packages may contain extensions (libraries) which other packages depend upon in order to function. For example, the modem application 'minicom' depends upon the package 'kermit' to provide minicom with the ability to transfer files using the kermit protocol.
parallel port - An interface from a computer system where data is transferred in or out in parallel; that is, on more than one wire. A parallel port carries one bit on each wire thus multiplying the transfer rate obtainable over a single wire. There will usually be some control signals on the port as well to say when data is ready to be sent or received. The most common kind of parallel port is a printer port; for example, a Centronics port which transfers eight bits at a time. Disks are also connected via special parallel ports; for example, SCSI or IDE.
password - A user identifies himself with a name and a password, the latter of which is a secret word or series of characters. On the RedRak, passwords are case sensitive. Here are some guidelines for selecting a password: Choose a password that is easy for you to remember but difficult for others to guess. The password should be at least six characters in length with mixed case; the first letter of a favorite phrase with missed letters is a good example. Also, include numbers and symbols. For example, using the phrase "It was the best of times!" the password could be Iwtbot6!
path - The specification of a node (file or directory) in a hierarchical file system. The path is usually specified by listing the nodes top-down, separating the directories by the pathname separator ("/" in Unix, "\" in MS-DOS). For example, a RedRak template creates a path called /public. You may create additional folders or files under that path, for example, to create this path: /public/onlinedoc/marketing.
ping - This stands for Packet InterNet Groper (ping was probably originally contrived to match submariners' term for the sound of a returned sonar pulse). A program used to test reachability of destinations by sending them one, or repeated, ICMP echo requests and waiting for replies. Since ping works at the IP level, its server-side is often implemented entirely within the operating system kernel and is therefore the lowest level test of whether a remote host is alive. Ping will often respond even when higher level, TCP-based services cannot. The term is also used as a verb: "Ping host X to see if it is up."
POP (Post Office Protocol) - A protocol designed to allow single user computers to retrieve electronic mail from a POP server. The POP server might be a computer with a permanent Internet connection whereas its clients might only connect to it occasionally, e.g. by modem. See "Setting up the RedRak as an IMAP and/or POP Mail Server" under "Mail Servers" under "RedRak Services" in the online help.
port - A logical channel or channel endpoint in a communications system. The Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) transport layer protocols used on Ethernet use port numbers to distinguish between different logical channels on the same network interface on the same computer. Each application program has a unique port number associated with it, defined in /etc/services or the Network Information Service "services" database. Some protocols, e.g. telnet and HTTP (which is actually a special form of telnet), have default ports specified but can use other ports as well. For example, the program that handles incoming telnet sessions uses port 23, and the program that handles HTTP uses port 80.
protocol - A set of formal rules describing how to transmit data, especially across a network. Low level protocols define the electrical and physical standards to be observed, bit- and byte-ordering and the transmission and error detection and correction of the bit stream. High level protocols deal with the data formatting, including the syntax of messages, the terminal to computer dialogue, character sets, sequencing of messages, etc.
queue - A first-in first-out data structure used to sequence multiple demands for a resource such as a printer, processor, or communications channel. Objects are added to the tail of the queue and taken off the head. A typical use of queues in an operating system involves a user command which places something on a queue, e.g. a file on a printer queue or a job on a job queue, and a background process or "daemon" which takes things off and processes them (e.g. prints or executes them). In the RedRak, the STORE command queues changes to be committed.
reboot - A boot with the implication that the computer has not been down for long.
reformat - A reorganization of a hard disk, starting with the lowest level of information storage. To reformat, all information should first be copied to a temporary storage area. That is because a reformat deletes all data on the hard disk. A brand new disk usually needs to be formatted, also called initialized. See "format" and "initialize."
restore - In RedRak, the restore process involves finding backed-up files stored on tape and copying them from the back-up medium to the RedRak.
root - The Unix superuser account (with user name "root" and user ID 0) that overrides file permissions.
router - On the Internet, a router is a device or, in some cases, software in a computer, that determines the next network point to which a packet should be forwarded toward its final destination. The router is connected to at least two networks and decides which way to send each information packet based on its current understanding of the state of the networks it is connected to. A router is located at any juncture of networks or router, including each Internet point-of-presence. A router is often included as part of a network switch. A router creates or maintains a table of the available routes and their conditions and uses this information along with distance and cost algorithms to determine the best route for a given packet. Typically, a packet may travel through a number of network points with routers before arriving at its destination.
serial port - A connector on a computer to which you can attach a serial line connected to peripherals which communicate using a serial (bit-stream) protocol. The most common type of serial port is a 25-pin D-type connector carrying RS-232 signals. Smaller connectors (e.g. 9-pin D-type) carrying a subset of RS-232 are often used on personal computers. The serial port is usually connected to an integrated circuit called a UART which handles the conversion between serial and parallel data. In the days before bit-mapped displays, and today on multi-user systems, the serial port was and is used to connect one or more terminals (teletypes or VDUs), printers, modems, and other serial peripherals. Two computers connected together via their serial ports, possibly via modems, can communicate using a protocol such as UUCP or PPP.
server - 1. A program that provides some service to other (client) programs. The connection between client and server is normally by means of message passing, often over a network, and uses some protocol to encode the client's requests and the server's responses. The server may run continuously (as a daemon), waiting for requests to arrive or it may be invoked by some higher level daemon which controls a number of specific servers (inetd on Unix). There are many servers associated with the Internet, such as those for Network File System, Network Information Service (NIS), Domain Name System (DNS), FTP, news, finger, Network Time Protocol. On Unix, a long list can be found in /etc/services or in the NIS database "services." 2. A computer which provides some service for other computers connected to it via a network. The most common example is a file server which has a local disk and services requests from remote clients to read and write files on that disk, often using Sun's Network File System (NFS) protocol or CIFS (Windows) or AppleTalk (Macintosh).
shell - The command interpreter used to pass commands to an operating system; so called because it is the part of the operating system that interfaces with the outside world. The most common Unix shells are the c shell (csh) and the Bourne shell (sh).
SMTP (Simple Mail Transfer Protocol) - SMTP is a TCP/IP protocol governing electronic mail transmission and reception. The details of SMTP are in RFC 821 of the Internet Engineering Task Force (IETF). An alternative to SMTP that is widely used in Europe is X.400. Also see "POP" and "IMAP," the two main protocols for reading e-mail from your server.
spool - To send files to some device or program (a "spooler" or daemon) that puts them in a queue for later processing of some kind. Usually, the spooler is the "print spooler" controlling output of jobs to a printer; but the term has been used in connection with other peripherals (especially plotters and graphics devices) and occasionally even for input devices. Also called a print queue.
STORE - This RedRak button saves all RedRak changes to be implemented (that is, committed) in a temporary queue. The changes in that queue become permanent and functional after you click the COMMIT button.
TCP/IP (Transmission Control Protocol over Internet Protocol) - The de facto standard Ethernet protocols incorporated into 4.2BSD Unix. This is the system networks use to communicate with each other on the Internet.
telnet - The Internet standard protocol for remote login. Runs on top of TCP/IP. Unix BSD networking software includes a program, telnet, which uses the protocol and acts as a terminal emulator for the remote login session. Sometimes abbreviated to TN.
template - RedRak templates are guides to assist in easily and accurately setting up your network. The RedRak has configuration templates, which are a set of defaults to assist you in setting up the RedRak program, a user web page template, and a template directory for home shares. All of the files in the template directory will be copied into each new user's directory.
traffic - In the RedRak, the Traffic Monitor Report tracks outgoing traffic (user visits) to external Internet sites including web sites, FTP, telnet, etc. Local Internet traffic is not tracked.
Unix - An interactive time-sharing operating system which is both powerful but at times confusing to use. The RedRak server makes full use of the power of Unix while eliminating the confusion. This is because RedRak users interact with the RedRak browser-based interface, which then implements the Unix commands. "Unix" or "UNIX"? Both seem roughly equally popular, perhaps with a historical bias towards the latter. "UNIX" is a trademark, however, since it is a name and not an acronym. Unix or Unix-like operating systems include OSF, Version 7, BSD, USG Unix, Xenix, Ultrix, Linux, and GNU. "Unix" has been adopted in this document. Since the operating system is case-sensitive and exists in many different versions, it is fitting that its name should reflect this.
upload - To transfer programs or data over a digital communications link from a smaller or peripheral "client" system to a larger or central "host" one.
URL (Uniform Resource Locator) - A standard for specifying the location of an object on the Internet, such as a file or a newsgroup. URLs are used extensively on the World-Wide Web. They are used in HTML documents to specify the target of a hyperlink which is often another HTML document (possibly stored on another computer). Here are some sample URLs: http://www.w3.org/default.html, ftp://wuarchive.wustl.edu/mirrors/msdos/graphics/gifkit.zip, mailto:dbh@doc.ic.ac.uk, news:alt.hypertext, telnet://dra.com. The part before the first colon specifies the access scheme or protocol. The part after the colon is interpreted according to the access scheme. In general, two slashes after the colon introduce a hostname. Host:port is also valid. The port number is usually omitted and defaults to the standard port for the scheme, e.g. port 80 for HTTP. For an HTTP or FTP URL the next part is a pathname which is usually related to the pathname of a file on the server.
volume - Similar to a hard disk partition, a volume is a finite-sized, named storage area existing on one or more hard disks. Volumes can be one of several types: normal, Raid 0 (stripe), Raid 1 (mirror), RAID 5, and noncontiguous. A normal volume uses one contiguous area on one disk. A stripe is a way of storing files across more than one disk. A mirror duplicates the same information on two or more disks. A RAID 5 array duplicates data on "n" disks over "n+1" disks. The redundancy in mirrors and RAID 5 arrays allows reconstruction of the data on a failed disk in the array without any data loss. A noncontiguous volume contains two or more noncontiguous areas across one or more disks. RedRak volume management allows you to create, modify and reconfigure (change volume type from normal to stripe, or from mirror to normal or stripe) volumes.
WAN (Wide Area Network) - A network, usually constructed with serial lines, extending over distances greater than one-half mile.
Web - "The Web" is the World Wide Web (WWW). The World Wide Web is an Internet client-server hypertext distributed-information retrieval system which originated from the CERN High-Energy Physics laboratories in Geneva, Switzerland in 1991. On the WWW everything (documents, menus, indices) is represented to the user as a hypertext object in HTML format. Hypertext links refer to other documents by their URLs. These can refer to local or remote resources accessible via FTP, Gopher, Telnet or news, as well as those available via the http protocol used to transfer hypertext documents. The client program (known as a browser), e.g. NCSA Mosaic, Netscape Navigator, Windows Explorer, etc., runs on the user's computer and provides two basic navigation operations: to follow a link or to send a query to a server. A variety of client and server software is freely available.
wildcard - A special character or character sequence which matches any character in a string comparison, like ellipsis (...) in ordinary written text.
zone - A logical group of network devices on AppleTalk.
Some definitions in this glossary are from whatis.com, copyright © 1996-98
whatis.com Inc., and The Free On-line Dictionary of
Computing, http://wombat.doc.ic.ac.uk/, Editor Denis Howe, copyright © 1993, 1998
Denis Howe.