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Glossary: CCNA & General Networking Terms 

 

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W3
See: World Wide Web
W3C
World Wide Web Consortium, a governing body for web standards.
WAIS
See: Wide Area Information Servers
WAE
See: Wireless Application Environment
WAN
See: Wide area network
WAP
See: Wireless Application Protocol
WDP
See: Wireless Datagram Protocol
WEP
See: Wired Equivalent Privacy
WLAN
See: Wireless Local Area Network
WML
See: Wireless Markup Language
WPA
See: Wi-Fi Protected Access
WSP
See: Wireless Session Protocol
WTA
See: Wireless Telephony Application
WTLS
See: Wireless Transport Layer Security protocol
WTP
See: Wireless Transaction Protocol
WebCrawler
A WWW search engine. The aim of the WebCrawler Project is to provide a high-quality, fast, and free Internet search service. The WebCrawler may be reached at "http://webcrawler.com/". [Source: WebCrawler's "WebCrawler Facts"]
WG
See: Working Group
White Book
a document produced for the JNT setting out the strategy to be adopted by the Academic Community in its transition from interim standards (Coloured Books) to ISO standards. Overtaken by history - an IP.
white pages
The Internet supports several databases that contain basic information about users, such as email addresses, telephone numbers, and postal addresses. These databases can be searched to get information about particular individuals. Because they serve a function akin to the telephone book, these databases are often referred to as "white pages. See also: Knowbot, netfind, whois, X.500. [Source: RFC1392]
Wi-Fi Protected Access (WPA)
A development of Wired Equivalent Privacy to overcome deficiencies in WEP as used in Wireless LANs, by incorporating elements of 802.11i security before the latter (to be known subsequently as WPA v2) is fully developed. Temporary Key Integrity Protocol (TKIP) is incorporated to allow different encryption keys for each packet transmitted, as are RADIUS support and facilities to stop rogue network points attracting authenticated users to steal their credentials. See also: RADIUS, Wired Equivalent Privacy.
Wireless Application Protocol (WAP)
A stack of protocols, akin to the OSI model or the TCP/IP stack, to implement the layers needed for communication with wireless devices, security, applications, etc, promoted as an open standard by the WAP Forum http://www.wapforum.org/.
Wireless Application Protocol Gateway
A WAP client may receive documents from an ordinary WWW server via a WAP gateway, a proxy which converts between WAP requests and HTTP requests (including CGI programs) and converts the output to WAP formats (e.g. WML or WMLScript) followed by compression to binary for sending to the client. WWW pages may also be coded directly in WML on the WWW server before receipt by the gateway.
Wireless Application Environment (WAE)
WAE is the programming environment for WAP. WAE is handled by a browser program in the device, and consists of Wireless Markup Language (WML), WMLScript and Wireless Telephony Application (WTA).
Wireless Datagram Protocol (WDP)
The transport layer of WAP, which transforms datagrams from upper layer protocols into the formats specific to datapaths, bearers and devices, e.g. GSM or SMS or GPRS. Thus upper layers have no need to program for the physical layer of communication such as air interface.
Wired Equivalent Privacy (WEP)
A security protocol within IEE standard 802.11b intended to give Wireless Local Area Networks the degree of privacy expected of fixed LANs. Encryption over air between the devices and fixed access points (rather than end to end) goes part way towards countering the eavesdropping risk of signals spilling out of buildings. However, the length of the key may be only 40 bits (up to 128 bits is allowed) even if WEP is turned on, and the encryption method produces some predictable sequences, so it is prone to statistical analysis to recover keys. Also the Service Set Identifier (SSID) is broadcast in clear in probes from the access point (unless turned off); this is used as a "password" for packets sent between members of specific LANs, so is useful for eavesdroppers to acquire, especially if obvious names are chosen e.g. 10Downing.

As an interim solution, the IEE 802.1x standard is available for port-level authentication and key management i.e. rapid changes and secure key delivery. This incorporates Extensible Authentication Protocol (EAP) from RFC 2284. This was first designed for wired (e.g. dialup) links, and is not itself a cipher standard, so the first version authenticates the MAC address rather than the user. The authentication is passed through from the fixed access point to an authentication server such as RADIUS or Kerberos. However, there are no checks that an access point is what it claims to be, so there is a way of masquerading or intercepting the authentication process.

Work on the 802.11i standard is ongoing at March 2003, but this addresses such issues as mutual and per-packet authentication, and could incorporate Advanced Encryption Standard (AES). An interim standard Wi-Fi Protected Access (WPA) contains some of the technologies to overcome WEP deficiencies.

It is imperative that further security measures are taken on top of WEP and its immediate successors, such as Virtual Private Network schemes, although Network Layer solutions such as IPsec are tricky when roaming devices use DHCP for dynamic IP addresses, and products orientated to wireless working are necessary. See also: 802.11, Kerberos, RADIUS, Wireless Local Area Network, Wireless Protected Access.

Wireless Local Area Network (WLAN)
A data network intended to serve an area of only a few hundres square metres or less, using radio communications between mobile computers and (typically) a fixed access point which provides onward connections to fixed networks such as the Internet. There are several competing technologies such as HIPERLAN in Europe and the 802.11 series in the USA. This is the next level up in distance from Personal Area Networks such as Bluetooth. See also: Bluetooth, 802.11, HIPERLAN.
Wireless Markup Language (WML)
The markup language for WAP, a tag-based language like HTML. Strictly, WML is a Document Type Definition (DTD) of eXtendable Markup Language, which implied a relationship with the DTD for (strictly defined) HTML.
Wireless Session Protocol (WSP)
The session layer of WAP, handling the interface between the application layer WAE and the transaction layer WTP. Sessions can be connection-orientated or connectionless, and can be suspended and resumed on demand.
Wireless Telephony Application (WTA)
The telephony interface for WAP, part of Wireless Application Environment (WAE). WTA can control telephony functions of the device from WML or WMLScript, or from requests from the network.
Wireless Transport Layer Security protocol (WTLS)
WTLS handles security for WAP, i.e. encryption, decryption, user authentication and data integrity checking of datagrams from upper layer protocols before passing to the transport layer WDP. It is based on the fixed network Transport Layer Security (TLS) protocol, formerly Secure Sockets Layer.
Wireless Transaction Protocol (WTP)
WTP is the transaction layer of WAP, which takes data packets from the session layer WSP and chops them into lower layer datagrams to pass to the security layer WTLS, or reassembles them at the far end. WTP also tracks sequences of sent and received packets, handling retransmissions or acknowledgements as required.
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. See also: Defense Data Network Network ..., white pages, Knowbot, X.500. [Source: FYI4]
Wide Area Information Servers (WAIS)
A distributed information service which offers simple natural language input, indexed searching for fast retrieval, and a "relevance feedback" mechanism which allows the results of initial searches to influence future searches. Public domain implementations are available. See also: archie, Gopher, Prospero. [Source: RFC1392]
Wide Area Network (WAN)
A network, usually constructed with serial lines, which covers a large geographic area. See also: Local Area Network, Metropolitan Area Network. [Source: RFC1392]
WML
See: Wireless Markup Language
WMLScript
A scripting language for WML, akin to Javascript or ECMAScript for HTML, which can control functions in the browser or the phone, using scripts downloaded from the server.
Working Group (WG)
A working group, within the IETF, is a group of people who work under a charter to achieve a certain goal. That goal may be the creation of an Informational document, the creation of a protocol specification, or the resolution of problems in the Internet. Most working groups have a finite lifetime. That is, once a working group has achieved its goal, it disbands. There is no official membership for a working group. Unofficially, a working group member is somebody who is on that working group's mailing list; however, anyone may attend a working group meeting. See also: Internet Engineering Task Force, Birds Of a Feather. [Source: RFC1983]
World Wide Web (WWW or W3)
A hypertext-based, distributed information system created by researchers at CERN in Switzerland. Users may create, edit or browse hypertext documents. The clients and servers are freely available. [Source: RFC1392]
workstation
A networked personal computing device with more power than a standard IBM PC or Macintosh. Typically, a workstation has an operating system such as unix that is capable of running several tasks at the same time. It has several megabytes of memory and a large, high-resolution display. Examples are Sun Sparcstations and Digital Alpha stations.
worm
A computer program which replicates itself and is self- propagating. Worms, as opposed to viruses, are meant to spawn in network environments. Network worms were first defined by Shoch & Hupp of Xerox in ACM Communications (March 1982). The Internet worm of November 1988 is perhaps the most famous; it successfully propagated itself on over 6,000 systems across the Internet. See also: Trojan Horse, virus. [Source: RFC1392]
WRT
With Respect To [Source: RFC1392]
WWW
See: World Wide Web
WYSIWYG
What You See is What You Get [Source: RFC1392]

 

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