Latest News
Updated:
04/21/2003
Is
802.11 Ready for VOIP?
5-Minute
Security Advisor - Strengthening Wireless Authentication
Catch-22
of WLANs
eWEEK
Excellence Awards: Networking Infrastructure
IEEE
Plots Speedier WLAN
Extreme
Springs Switch Surprise
Nortel
Launches WWAN-WLAN Products
Nortel
Preps 'Security Switch'
Wi-Fi
Developers Pursue Plans for More Services
How
to Fine-Tune Your VPN Strategy
Cisco
to Buy Linksys
Verizon's
Surprise Evolution
WLANs
Spur Security Questions
Verizon
Plans 2.4-Mbits/s Wireless Rollout
Study
Exposes WLAN Security Risks
Roaming
From WLAN to WAN
Wireless
Clouds Of Connectivity
WLAN:
The Four S's
Cisco
Bolsters Its WLAN Hand
Cisco
to License WLAN Technology
Telesuite
Virtual Conference Room
IBM
Connects Wireless Networks, Enterprise Systems
Ten
Steps to a Secure Wireless Network
Top
Vulnerabilities in Web Applications
Hospital
Cures WLAN Insecurity
System
Boosts WLAN Security
Glossary
2G or second generation - a term for analog and digital current networks operating on 800 MHz or 1900 MHz spectrums. These include Advanced Mobile Phone Service (AMPS), Time Division Multiple Access (TDMA), Global System for Mobile Communications (GSM), and Code Division Multiple Access (CDMA).
3G or third generation - also
known as Universal Mobile Telecommunications System (UMTS). 3rd Generation
standards boost additional services, more extensive roaming capabilities
and transfer rates 26x faster than those allowed by current CDMA networks.
802.11 refers to a family of specifications developed by the IEEE for wireless LAN (Local Area Network) technology. 802.11 specifies an over-the-air interface between a wireless client and a base station or between two wireless clients. The IEEE accepted the specification in 1997.
The most significant specifications in the 802.11 family are:
802.11a (also referred to as Wi-Fi5) - an extension to 802.11 that applies to wireless LANs and provides up to 54 Mbps (Megabits per second) in the 5 GHz (Gigahertz) band.
802.11b (also referred to as Wi-Fi) - an extension to 802.11 that applies to wireless LANS and provides 11 Mbps transmission (with a fallback to 5.5, 2 and 1 Mbps) in the 2.4 GHz band. 802.11b uses only DSSS. 802.11b was a 1999 ratification to the original 802.11 standard, allowing wireless functionality comparable to Ethernet.
802.11g -- applies to wireless LANs and provides 20+ Mbps in the 2.4 GHz band.
802.1x - If your wireless clients happen to run Windows XP, a strong alternative is IEEE 802.1x. 802.1x provides a carrier for secure delivery of session keys used to encrypt traffic between the supplicant and authenticator, addressing a serious omission in the WEP standard. For example, session keys might be created "on the fly" by the access point or supplied by a RADIUS server. If a hacker recovered keys from WEP session traffic, the keys would be of no value for other sessions.
Ad-Hoc Mode - Each client communicates directly with the other clients within the network. Ad-hoc mode is designed such that only the clients within transmission range (within the same cell) of each other can communicate. If a client in an ad-hoc network wishes to communicate outside of the cell, a member of the cell MUST operate as a gateway and perform routing.
CDMA - CDMA stands for Code Division
Multiple Access. It is the underlying
technology that enables millions of wireless phones to communicate where
wireless carriers have implemented the technology in their wireless networks.
CDPD - operates as an overlay
on analog cellular networks (AMPS) to allow packetized data transfer,
which increases the speed and efficiency of old analog networks.
DHCP - Stands for Dynamic Host Configuration Protocol, a protocol for assigning dynamic IP addresses to devices on a network. With dynamic addressing, a device can have a different IP address every time it connects to the network. In some systems, the device's IP address can even change while it is still connected. DHCP also supports a mix of static and dynamic IP addresses. DHCP client support is built into Windows 95 and NT workstation. NT 4 server includes both client and server support.
digital cellular systems - standards which utilize digital transmissions such as TDMA, CDMA, IS, and GSM.
DMZ - Demilitarized Zone - a networking term for a specially designed network segment where external users are allowed to access resources without getting any access to internal networks.
Ethernet - A local-area network
(LAN) architecture developed by Xerox Corporation in cooperation with
DEC and Intel in 1976. Ethernet uses a bus or star topology and supports
data transfer rates of 10 Mbps. The Ethernet specification served as the
basis for the IEEE 802.3 standard. It is one of the most widely implemented
LAN standards.
A newer version of Ethernet, called 100Base-T (or Fast Ethernet), supports
data transfer rates of 100 Mbps. The newest version, Gigabit Ethernet
supports data rates of 1 gigabit (1,000 megabits) per second.
IEEE - The IEEE (Eye-triple-E) is a nonprofit, technical professional association of more than 375,000 individual members in 150 countries. The full name is the Institute of Electrical and Electronics Engineers, Inc., although the organization is most popularly known and referred to by the letters I-E-E-E. Through its members, the IEEE is a leading authority in technical areas ranging from computer engineering, biomedical technology and telecommunications, to electric power, aerospace and consumer electronics, among others.
Infrastructure mode - Each client sends all of its communications to a central station, or access point (AP). The access point acts as an Ethernet bridge and forwards the communications onto the appropriate network-either the wired network, or the wireless network.
IPSEC - Short for IP Security, a set of protocols to support secure exchange of packets at the IP layer. IPsec has been deployed widely to implement Virtual Private Networks (VPNs).
MAC Address - Short for Media Access Control address. The MAC address is a 12-character code that is unique to every single piece of network interface hardware. MAC codes are applied at the time of production by the manufacturer, therefore, it is possible to limit 802.11 users according to the device's unique MAC address.
PCS spectrum - personal communication
services (PCS) operates at the 1900 MHz spectrum and is entirely digital
(includes digital cellular standards such as TDMA, CDMA, and GSM but not
analog standards).
SSH - Developed by SSH Communications Security Ltd., Secure Shell is a program to log into another computer over a network, to execute commands in a remote machine, and to move files from one machine to another. It provides strong authentication and secure communications over insecure channels. SSH protects a network from attacks such as IP spoofing, IP source routing, and DNS spoofing. An attacker who has managed to take over a network can only force SSH to disconnect. He or she cannot play back the traffic or hijack the connection when encryption is enabled. When using SSH's login the entire login session, including transmission of password, is encrypted; therefore it is almost impossible for an outsider to collect passwords.
SSL - Short for Secure Sockets Layer, a protocol developed by Netscape for transmitting private documents via the Internet. SSL works by using a public key to encrypt data that's transferred over the SSL connection. Both Netscape Navigator and Internet Explorer support SSL and many Web sites use the protocol to obtain confidential user information, such as credit card numbers. By convention, URLs that require an SSL connection start with https: instead of http:.
switching center - mobile system
sends radio signals to switching center. Switching center chooses the
appropriate network link to propagate signal (public/private network via
telephone or other high speed line). The signal is then passed onto an
organization's existing LAN/WAN infrastructure.
VLAN - Short for virtual LAN, a network of computers that behave as if they are connected to the same wire even though they may actually be physically located on different segments of a LAN. VLANs are configured through software rather than hardware, which make them extremely flexible. One of the biggest advantages of VLANs is that when a computer is physically moved to another location, it can stay on the same VLAN without any hardware reconfiguration.
VPN - Stands for Virtual Private Network, a network that is constructed by using public wires to connect nodes. For example, there are a number of systems that enable you to create networks using the Internet as the medium for transporting data. These systems use encryption and other security mechanisms to ensure that only authorized users can access the network and that the data cannot be intercepted.
WAP - a universal specification
to facilitate the delivery and presentation of Web-based data and services
on mobile phones and devices with small displays and limited input facilities.
War Driving - War driving is when hackers drive around in a car equipped with wireless gear looking for illicit access to unsecured wireless networks.
WECA - Wireless Ethernet Compatibility
Alliance. WECA's mission is to certify interoperability of Wi-Fi (IEEE
802.11) products and to promote Wi-Fi as the global wireless LAN standard
across all market segments.
WEP - Short for Wired Equivalent Privacy, a
security protocol for wireless local area networks (WLANs) defined in
the 802.11b (Wi-Fi) standard. WEP is designed to provide the same level
of security as that of a wired LAN. LANs are inherently more secure than
WLANs because LANs are somewhat protected by the physical nature of their
structure, having some or all parts of the network inside a building that
can be protected from unauthorized access. WLANs, which are over radio
waves, do not have the same physical structure and therefore are more
vulnerable to tampering. WEP aims to provide security by encrypting data
over radio waves so that it is protected as it is transmitted from one
end point to another. However, it has been found that WEP is not as secure
as once believed.
Wi-Fi - Wireless Fidelity (synonymous with 802.11b).