This document explains topics relating to wireless networks. The main topics discussed include, what type of vulnerabilities exist today in 802.11 networks and ways that you can help prevent these vulnerabilities from happening. Wireless networks have not been around for many years. Federal Express has been using a type of wireless networks, common to
802.11 networks used today, but general public has recently just started to use wireless networking technology. Because of weak security that exists in wireless networks, companies such as Best Buy have decided to postpone roll-out of wireless technology. The United States Government has done likewise and is suspending use of wireless until a more universal, secure solution is available.Background
What is Wireless?
Wireless LANs or Wi-Fi is a technology used to connect computers and devices together. Wireless LANs give persons more mobility and flexibility by allowing workers to stay connected to Internet and to network as they roam from one coverage area to another. This increases efficiency by allowing data to be entered and accessed on site.
Besides being very simple to install, WLANs are easy to understand and use. With few exceptions, everything to do with wired LANs applies to wireless LANs. They function like, and are commonly connected to, wired Ethernet networks.
The Wireless Ethernet Compatibility Alliance [WECA] is industry organization that certifies 802.11 products that are deemed to meet a base standard of interoperability. The first family of products to be certified by WECA is that based on 802.11b standard. This set of products is what we will be studying. Also more standards exist such as 802.11a and 802.11g.
The original 802.11 standard was published in 1999 and provides for data rates at up to 2 Mbps at 2.4 GHz, using either FHSS or DSSS. Since that time many task groups have been formed to create supplements and enhancements to original 802.11 standard.
The 802.11b TG created a supplement to original 802.11 standard, called 802.11b, which has become industry standard for WLANs. It uses DSSS and provides data rates up to 11 Mbps at 2.4 Ghz. 802.11b will eventually be replaced by standards which have better QoS features, and better security.
Network Topology
There are two main topologies in wireless networks which can be configured: Peer-to-peer (ad hoc mode) This configuration is identical to its wired counterpart, except without wires. Two or more devices can talk to each other without an AP.
Client/Server (infrastructure networking) This configuration is identical to its wired counterpart, except without wires. This is most common wireless network used today, and what most of concepts in this paper apply to.
Benefits of Wireless LANs
WLANs can be used to replace wired LANs, or as an extension of a wired infrastructure. It costs far less to deploy a wireless LAN than to deploy a wired one. A major cost of installing and modifying a wired network is expense to run network and power cables, all in accordance with local building codes. Example of additional applications where decision to deploy WLANs include: Additions or moves of computers. Installation of temporary networks Installation of hard-to-wire locations
Wireless LANs give you more mobility and flexibility by allowing you to stay connected to Internet and to network as you roam.
Cons of Wireless LANs
Wireless LANs are a relatively new technology which has only been around since 1999. With any new technology, standards are always improving, but in beginning are unreliable and insecure. Wired networks send traffic over a dedicated line that is physically private; WLANs send their traffic over shared space, airwaves. This introduces interference from other traffic and need for additional security. Besides interference from other wireless LAN devices, 2.4 GHz is also used by cordless phones and microwaves.
Security Issues of WLANs
War-driving War-driving is a process in which an individual uses a wireless device such as a laptop or PDA to drive around looking for wireless networks. Some people do this as a hobby and map out different wireless networks which they find. Other people, who can be considered hackers, will look for wireless networks and then break into networks. If a wireless is not secure, it can be fairly easy to break into network and obtain confidential information. Even with security, hackers can break security and hack. One of most prevalent tools used on PDAs and Microsoft windows devices is, Network Stumbler, which can be downloaded at http://www.netstumbler.com. Equipped with software and device, a person can map out wireless access points if a GPS unit is attached. Adding an antenna to wireless card increases capabilities of Wi-Fi. More information can be found at: http://www.wardriving.info and http://www.wardriving.com to name a few.
War-chalking War-chalking is a method of marking wireless networks by using chalk most commonly. War-driving is usually method used to search for networks, and then person will mark network with chalk that gives information about network. Some of information would include, what network name is, whether network has security, and possibly contact information of who owns network. If your wireless network is War-chalked and you don't realize it, your network can be used and/or broken into faster, because of information shown about your network.
Eavesdropping & Espionage Because wireless communication is broadcast over radio waves, eavesdroppers who just listen over airwaves can easily pick up unencrypted messages. These intruders put businesses at risk of exposing sensitive information to corporate espionage. Wireless LAN Security What Hackers Know That You Don't www.airdefense.net Copyright 2002
Internal Vulnerabilities Within an organization network security can be compromised by ways such as, Rouge WLANs (or Rouge Aps), Insecure Network Configuration, and Accidental Associations to name a few.
Rouge Access Points An employee of an organization might hook up an access point without permission or even knowledge of IT. This is simple to do, all a person has to do is plug an Access point or wireless router into an existing live LAN jack and they are on network. One statistic in 2001 by Gartner said that, at least 20 percent of enterprises already have rouge access points. Another type of attack would be if, someone from outside organization, enters into workplace and adds an Access Point by means of Social Engineering.
