IndexContents Page No.1 Introduction 12 Types Of Wireless Lans 13 Wireless Fidelity 24 Wlan Components 34.1 Access Points 34.2 Network Interface Cards (Nics)/Client Adapters 45 Wlan Architecture 45.1 Independent Wlan 45.2 Infrastructure Wlan 55.3 Microcells And Roaming 56 Ieee 802.11 Architectures 66.1 Basic Wlan Architecture 77 Benefits Of Wireless Lans 87.1 Simplified Implementation And Maintenance 87.2 Extended Reach 87.3 Increased Worker Mobility 87.4 Reduced Total Cost Of Ownership And Operation 88 Wireless Lan Topology 98.1 Wi-Fi Channels 99 Threats To Wlan Environments 109.1 Type Of Attacks 1110 Security Features Of Wireless Lans 1210.1 Authentication 1310.2 Association 1410.3 Encryption And Decryption-The Wep Protocol 1411 Wireless Lan Monitoring Tool 1611.1 How It Works 1611.2 Use Wifi Manager Tool 1612 Features 1713 New Standards For Improving Wlan Security 1813.1 Advanced Encryption Standard (Aes) 1814 Temporal Key Integrity Protocol (Tkip) 1915 Tools For Protecting Wlan 2016 Conclusion 2217 References 23

1 INTRODUCTION1

Wireless local area networks (WLANs) based on the Wi-Fi (wireless fidelity) standards are

one of today's fastest growing technologies in businesses, schools, and homes, for good

reasons. They provide mobile access to the Internet and to enterprise networks so users can

remain connected away from their desks. These networks can be up and running quickly

when there is no available wired Ethernet infrastructure. They can be made to work with a

minimum of effort without relying on specialized corporate installers.

Wireless LANs are a boon for organizations that don't have time to setup wired LANs, make

networked temporary offices a reality and remove the wire work that goes on in setting

LANs. They are reported to reduce setting up costs by 15%. But, with these benefits come the

security concerns. One doesn't need to have physical access to your wires to get into your

LANs now. Any attacker, even though sitting in your parking lot, or in your neighboring

building, can make a mockery of the security mechanisms of your WLAN. If you don't care

about security, then go ahead; buy those WLAN cards/ Access Points. But, if you do, watch

out for the developments on the security front of 802.11. As this report and many such others

tell, contrary to 802.11's claims, WLANs have very little security. An attacker can listen to

you, take control of your laptops/desktops and forge him to be you. He can cancel your

orders, make changes into your databases, or empty your credit cards.

Think like an attacker and take proper countermeasures. Have dynamic system

administrators. Those attackers won't be lucky every time! The key is, be informed! Wireless

LANs (WLANs) are quickly gaining popularity due to their ease of installation and higher

employee mobility. Together with PDAs and other mobility devices, they go on to improve

the quality of life

2 TYPES OF WIRELESS LANS

The part of success behind the popularity of WLANs is due to the availability of the 802.11

standard from IEEE. The standard specifies operation of WLANs in three ways:

Infrastructure Mode: Every WLAN workstation (WS) communicates to any machine

through an access point (AP). The machine can be in the same WLAN or connected to

the outside world through the AP.

Ad Hoc Network Mode: Every WS talks to another WS directly.

2

Mixed Network Mode: Every WS can work in the above two modes simultaneously.

This is also called the Extended Basic Service Set (EBSS)

FIG.1 TYPE OF WIRELESS LAN

3 WIRELESS FIDELITY

Wi-Fi, or Wireless Fidelity is freedom : it allows you to connect to the internet from your

couch at home, in a hotel room or a conference room at work without wires . Wi-Fi is a

wireless technology like a cell phone. Wi-Fi enabled computers send and receive data indoors

and out; anywhere within the range of a base station. And the best thing of all, it is fast.

However you only have true freedom to be connected any where if your computer is

configured with a Wi-Fi CERTIFIED radio (a PC card or similar device). Wi-Fi certification

means that you will be able to connect anywhere there are other Wi-Fi CERTIFIED products

- whether you are at home , office , airports, coffee shops and other public areas equipped

with a Wi-Fi access availability. Wi-Fi will be a major face behind hotspots , to a much

greater extent. More than 400 airports and hotels in the US are targeted as Wi-Fi hotspots.

3

The Wi-Fi CERTIFIED logo is your only assurance that the product has met rigorous

interoperability testing requirements to assure products from different vendors will work

together. The Wi-Fi CERTIFIED logo means that it is a "safe" buy.

Wi-Fi certification comes from the Wi-Fi Alliance, a non profit international trade

organisation that tests 802.11 based wireless equipment to make sure that it meets the Wi-Fi

standard and works with all other manufacturer's Wi-Fi equipment on the market. The Wi-Fi

Alliance (WELA) also has a Wi-Fi certification program for Wi-Fi products that meet

interoperability standards. It is an international organisation devoted to certifying

interoperability of 802.11 products and to promoting 802.11as the global wireless LAN std

across all market segment.

• Wi-Fi (short for “Wireless Fidelity") is the popular term for a high-frequency

wireless local area network (WLAN) -Promoted by the Wi-Fi Alliance (Formerly

WECA - Wireless Ethernet Carriers Association)

• Used generically when referring to any type of 802.11 network, whether 802.11a,

802.11b, 802.11g, dual-band, etc. The term is promulgated by the Wi-Fi Alliance

4 WLAN COMPONENTS

One important advantage of WLAN is the simplicity of its installation. Installing a wireless

LAN system is easy and can eliminate the needs to pull cable through walls and ceilings. The

physical architecture of WLAN is quite simple. Basic components of a WLAN are access

points (APs) and Network Interface Cards (NICs)/client adapters.

4.1 Access Points

Access Point (AP) is essentially the wireless equivalent of a LAN hub. It is typically

connected with the wired backbone through a standard Ethernet cable, and communicates

with wireless devices by means of an antenna. An AP operates within a specific frequency

spectrum and uses 802.11 standard specified modulation techniques. It also informs the

wireless clients of its availability, and authenticates and associates wireless clients to the

wireless network.

4.2 Network Interface Cards (NICs)/client adapters

4

Wireless client adapters connect PC or workstation to a wireless network either in ad hoc

peer-to-peer mode or in infrastructure mode with APs (will be discussed in the following

section). Available in PCMCIA (Personal Computer Memory Card International Association)

card and PCI (Peripheral Component Interconnect), it connects desktop and mobile

computing devices wirelessly to all network resources. The NIC scans the available

frequency spectrum for connectivity and associates it to an access point or another wireless

client. It is coupled to the PC/workstation operating system using a software driver. The NIC

enables new employees to be connected instantly to the network and enable Internet access in

conference rooms.

5 WLAN ARCHITECTURE

The WLAN components mentioned above are connected in certain configurations. There are

three main types of WLAN architecture: Independent, Infrastructure, and Microcells and

Roaming.

5.1 Independent WLAN

The simplest WLAN configuration is an independent (or peer-to-peer) WLAN. It is a group

of computers, each equipped with one wireless LAN NIC/client adapter. In this type of

configuration, no access point is necessary and each computer in the LAN is configured at the

same radio channel to enable peer-to-peer networking. Independent networks can be set up

whenever two or more wireless adapters are within range of each other.

FIG.2 INDEPENDENT WLAN

5.2 Infrastructure WLAN

5

Infrastructure WLAN consists of wireless stations and access points.

Access Points combined with a distribution system (such as Ethernet) support the creation of

multiple radio cells that enable roaming throughout a facility. The access points not only

provide communications with the wired network but also mediate wireless network traffic in

the immediate neighborhood. This network configuration satisfies the need of large-scale

networks arbitrary coverage size and complexities.

FIG. 3 INFRASTRUCTURE WLAN CONSISTS OF WIRELESS STATIONS AND ACCESS POINTS.

5.3 Microcells and Roaming

The area of coverage for an access point is called a "microcell’. The installation of multiple

access points is required in order to extend the WLAN range beyond the coverage of a single

access. One of the main benefits of WLAN is user mobility. Therefore, it is very important to

ensure that users can move seamlessly between access points without having to log in again

and restart their applications. Seamless roaming is only possible if the access points have a

way of exchanging information as a user connection is handed off from one access point to

another. In a setting with overlapping microcells, wireless nodes and access points frequently

check the strength and quality of transmission. The WLAN system hands off roaming users

to the access point with the strongest and highest quality signal, in accommodating roaming

from one microcell to another.

6

FIG. 4 MICROCELLS AND ROAMING

6 IEEE 802.11 ARCHITECTURES

In IEEE's proposed standard for wireless LANs (IEEE 802.11), there are two different ways

to configure a network: ad-hoc and infrastructure. In the ad-hoc network, computers are

brought together to form a network "on the fly." As shown in Figure 1, there is no structure to

the network; there are no fixed points; and usually every node is able to communicate with

every other node. A good example of this is the aforementioned meeting where employees

bring laptop computers together to communicate and share design or financial information.

Although it seems that order would be difficult to maintain in this type of network,

algorithms such as the spokesman election algorithm (SEA) [4] have been designed to "elect"

one machine as the base station (master) of the network with the others being slaves. Another

7

algorithm in ad-hoc network architectures uses a broadcast and flooding method to all other

nodes to establish who's who.

6.1 Basic WLAN Architecture

FIG. 5 BASIC WLAN

Some of the business advantages of WLANs include

" Mobile workers can be continuously connected to their crucial applications and data;

" New applications based on continuous mobile connectivity can be deployed;

" Intermittently mobile workers can be more productive if they have continuous access to

email, instant messaging, and other applications;

" Impromptu interconnections among arbitrary numbers of participants become possible.

" But having provided these attractive benefits, most existing WLANs have not effectively

addressed security-related issues.

7 BENEFITS OF WIRELESS LANS

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A traditionally wired 10/100 BaseT Ethernet LAN infrastructure for 100 people costs about

US$15,000 and requires several days to install (see Figure 1). Enterprises that use such an

arrangement also incur additional costs and disruptions with every change to the physical

office. (Expenses vary according to the physical layout and the quality of the equipment

used.) Conversely, wireless LANs are less expensive and less intrusive to implement and

maintain, as user needs change.

7.1 Simplified Implementation And Maintenance

Wireless APs can be placed in the ceiling, where they can accommodate a virtually endless

variety of office configurations (see Figure 2). Wired LANs, in contrast, consume time and

resources to run cables from a network closet to user’s desktops and to difficult-to-service

areas such as conference room tables and common areas. With a wired LAN, each additional

user or modification to the floor plan necessitates adjustments to the cabling system.

7.2 Extended Reach

Wireless LANs enable employees to access company resources from any location within an

AP’s transmission range. This flexibility and convenience can directly improve employee

productivity.

7.3 Increased Worker Mobility

The roaming benefits of wireless LANs extend across all industries and disciplines. The shop

foreman can manage logistics from the warehouse as easily as office-based employees move

about the building with their laptops or PDAs. And field sales employees can connect to

public wireless LANs in coffee shops and airport lounges.

7.4 Reduced Total Cost Of Ownership And Operation

The cumulative benefits of simplified implementation and maintenance, an extended LAN

reach, and the freedom to roam minimize expenses and improve organizational and employee

productivity. The result is reduced total cost of ownership and operation.9

8 WIRELESS LAN TOPOLOGY

• Wireless LAN is typically deployed as an extension of an existing wired network as

shown below. 

FIG.6 LAN TOPOLOGY

8.1 Wi-Fi Channels

• Wireless LAN communications are based on the use of radio signals to exchange

information through an association between a wireless LAN card and a nearby access

point.

• Each access point in an 802.11b/g network is configured to use one radio frequency

(RF) channel.

• Although the 802.11b/g specifications indicate that there are fourteen (14) channels

that can be utilized for wireless communications, in the U.S., there are only eleven

channels allowed for AP use. In addition, since there is frequency overlap among

many of the channels, there must be 22 MHz separation between any two channels in

use.

• In a multi-access point installation, where overlapping channels can cause

interference, dead-spots and other problems, Channels 1, 6 and 11 are generally

10

regarded as the only safe channels to use. Since there are 5 5MHz channels between 1

and 6, and between 6 and 11, or 25MHz of total bandwidth, that leaves three MHz of

buffer zone between channels.

• In practice, this constraint limits the number of useable channels to three (channels 1,

6, and 11). 802.11a wireless networks have eight non-overlapping channels which

provide more flexibility in terms of channel assignment.

• For example, 802.11a - An extension to the IEEE 802.11 standard that applies to

wireless LANs and provides up to 54 Mbps in the 5GHz band.

• For the North American users, equipment available today operates between

5.15 and 5.35GHz.

• This bandwidth supports eight separate, non-overlapping 200 MHz channels.

• These channels allow users to install up to eight access points set to different channels

without interference, making access point channel assignment much easier and

significantly increasing the level of throughput the wireless LAN can deliver within a

given area.

• If two access points that use the same RF channel are too close, the overlap in their

signals will cause interference, possibly confusing wireless cards in the overlapping

area.

• To avoid this potential scenario, it is important that wireless deployments be carefully

designed and coordinated.

• It is also critical to make sure that deployment does not cause conflicts with other pre-

existing wireless implementations.

9 THREATS TO WLAN ENVIRONMENTS

All wireless computer systems face security threats that can compromise its systems and

services. Unlike the wired network, the intruder does not need physical access in order to

pose the following security threats:

Eavesdropping This involves attacks against the confidentiality of the data that is being

transmitted across the network. In the wireless network, eavesdropping is the most significant

threat because the attacker can intercept the transmission over the air from a distance away

from the premise of the company.

11

FIG.7 WLAN ENVIRONMENT

Tampering The attacker can modify the content of the intercepted packets from the wireless

network and this results in a loss of data integrity.

Unauthorized access and spoofing The attacker could gain access to privileged data and

resources in the network by assuming the identity of a valid user. This kind of attack is

known as spoofing. To overcome this attack, proper authentication and access control

mechanisms need to be put up in the wireless network.

Denial of Service In this attack, the intruder floods the network with either valid or invalid

messages affecting the availability of the network resources. The attacker could also flood a

receiving wireless station thereby forcing to use up its valuable battery power.

Other security threats The other threats come from the weakness in the network

administration and vulnerabilities of the wireless LAN standards, e.g. the vulnerabilities of

the Wired Equivalent Privacy (WEP), which is supported in the IEEE 802.11 wireless LAN

standard.

9.1 Type of Attacks

The following known attacks are known to be effective:

• Passive Attacks

1 Dictionary based attacks

2 Cracking the WEP key

• Active attacks12

1 Authentication Spoofing

2 Message Injection

3 Message Modification

4 Message Decryption

5 Man in the Middle Attack

As with other networks, the active attacks are riskier but provide greater powers to the

attacker.

Passive Attacks Active attacks

No risk involved

No need to be the part of networks, because

the WLAN cards support monitor mode,

whereby one can listen to the

communication without being a part of the

network

The attacker can only listen to whatever is

going on. He can not fiddle with the

network

Riskier

The attacker has to first get into the

network, before doing damages

The attacker can interrupt, hijack and

control

the network at his will

10 SECURITY FEATURES OF WIRELESS LANS

A message traveling by air can be intercepted without physical access to the wiring of an

organization. Any person, sitting in the vicinity of a WLAN with a transceiver with a

capability to listen/talk, can pose a threat. Unfortunately, the same hardware that is used for

WLAN communication can be employed for such attacks.

To make the WLANs reliable the following security goals were considered:

• Confidentiality

• Data Integrity

• Access Control

The following security measures are a part of the 802.11 IEEE protocol:

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• Authentication

• Association

• Encryption

The need of a client to be mobile brought in the separation of authentication and association

processes. Since a client frequently changes AP boundaries, he can be authenticated to

various AP at a given point, yet remains associated to his chosen one. Before a client gets

associated to other, he must be first authenticated.

FIG: 8 AUTHENTICATION & ASSOCIATION

10.1 Authentication

802.11 specify two authentication mechanisms:

1 Open system authentication

2 Shared key authentication

• Open system authentication

A client needs an SSID for successful Association. Any new client that comes in an EBSS

area is provided with an SSID. This is equivalent to no security.

14

FIG : 9 OPEN SYSTEM AUTHENTICATION

• Shared system authentication

The client cannot authenticate himself if he doesn't have the WEP shared secret key. WEP

protocol is used for encryption.

FIG : 9 SHARED KEY AUTHENTICATION

10.2 Association

An SSID is used to differentiate two networks logically. To successfully associate to a WS,

one must have the SSID of the other WS. This was not intended to be a security feature, and

in fact SSID is sent in open in the beacon frame of the AP.

10.3 Encryption and Decryption-The WEP Protocol

The WLAN administrator has an option (if the administrator decides to send the packets

unencrypted) to make all the communication over the air encrypted, i.e. every frame that is

below the Ethernet Header is encrypted using the WEP protocol. The WEP protocol has

three components:

• A shared secret key, k (40bit /104 bit): The fact that the secret key is shared helps reduce

the load on AP, while simultaneously assuming that whoever is given the secret key is a

trusted person. This shared key is never sent over the air.802.11 doesn't discuss the

deployment of this key onto Work Stations. It has to be installed manually at each WS/AP.

Most APs can handle up to four shared secret keys.

• Initialization vector, IV (24 bit): IV is a per-packet number that is sent in clear over the air.

This number is most effective if generated randomly, because it is used as one of the inputs to

the RC4 algorithm. 802.11 don’t specify generation of IV. Infact, many cards generate IVs in

linear fashion, i.e., 1,2,3…

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• RC4 algorithm, RC4 (IV, k): This algorithm is used to generate a key stream K, length

equal to that of the message to be transmitted by the data-link layer. It takes the IV and k as

inputs.

FIG :10 ENCRYPTION & DECRYPTION ON WEP

FIG :11 ENCRYPTION

11 WIRELESS LAN MONITORING TOOL

Manage Engine WiFi Manager is an integrated and centralized management and security

solution for wireless networks (WLANs) for enterprises. It enhances the availability and 16

security of your WLANs by continuously monitoring the network as well as the airspace.

WiFi Manager offers wireless device monitoring, one-click configuration, access point

firmware management, wireless security management and a variety of reports that remove the

complexity of wireless network management. WiFi Manager can detect almost all major

wireless threats including rogue attacks, intrusions, sniffers, DoS attacks, and vulnerabilities.

With WiFi Manager you'll have complete control over your wireless devices as well as your

airspace, and more time to focus on core IT operations.

11.1 How It Works

WiFi Manager comprises of 2 components:

WiFi Manager Server

RF Sensors

Administrators can download the WiFi Manager server from our website and install it in the

LAN to perform integrated wireless and wired network management. RF sensors are optional

hardware components that are distributed throughout the physical environment, providing

WLAN protection wherever needed. The WiFi Manager server aggregates, analyzes, and

persists the data fed by the sensors. WiFi Manager presents a neat Web-based user interface

that can be accessed from anywhere using a standard HTML browser.

11.2 Use WiFi Manager Tool

Identify rogue wireless devices

Know who is using your WLAN

Know what access points are connected to your WLAN

Monitor your WLAN devices

Monitor Access Point bandwidth utilization

Configure your WLAN Access Points

Enhance and enforce wireless LAN security.

Proactively manage the network problems before they impact the network.

Identify network bottlenecks, reduce downtime, and to improve network health and

performance.

Troubleshoot network problems.

17

Capture and decode wireless traffic for testing and troubleshooting.

Upgrade firmware, schedule upgrades, and audit them.

Enforce no WLAN policy.

FIG.12 USE WIFI MANAGER

12 FEATURES

Continuous RF Monitoring

Using integrated RF sensors WiFi Manager analyses the RF spectrum for all 802.11

conversations and identifies intrusions, attacks, vulnerabilities, and policy violations. Local

analysis and intelligent data forwarding ensures low bandwidth consumption between sensors

and the software. These sensors require zero configurations making it truly plugand- play.

Rogue Detection & Blocking

Multiple techniques involving RF and wired side inputs are employed to detect rogue access

points. Once detected, WiFi Manager provides details such as nearest sensor and switch port

mapping for the administrators to locate and block the rogue AP from the network.

Attack Mitigation

WiFi Manager reduces the impact of wireless attacks by detecting them before hand. It

detects all major attacks including RF jamming attack, AirJack attack,

ASLEAP attack, Fata-jack attack, EAPoL logoff Storm, EAPoL Start Storm etc.

12.4Access Point Configuration

18

Using WiFi Manager administrators can configure access point for basic settings, radio

settings, access control settings, security settings, and services settings. Administrators can

either fill in predefined configuration templates and push the values to select access points or

group access points based on model, firmware version etc., and configure them in bulk.

Firmware Upgrade

WiFi Manager facilitates remote firmware upgrade of access points. Upgrades can also be

scheduled for later execution.

Wired & Wireless Network Monitoring

WiFi Manager monitors access points and other network devices for availability, SNMP

reachability, traffic, and utilization. It generates specific reports for WLANs including radio

reports, error reports, association reports, and security reports.

Troubleshooting

Web-based GUI enables quick access to alarms, reports, configuration history etc.,

facilitating easy troubleshooting

13 NEW STANDARDS FOR IMPROVING WLAN SECURITY

Apart from all of the actions in minimizing attacks to WLAN mentioned in the previous

section, we will also look at some new standards that intend to improve the security of

WLAN

13.1 Advanced encryption Standard (AES)

Advanced Encryption Standard is gaining acceptance as appropriate replacement for RC4

algorithm in WEP. AES uses the Rijandale Algorithm and supports the following key lengths

" 128 bit key

" 192 bit key

" 256 bit key

AES is considered to be un-crackable by most Cryptographers. NIST has chosen AES for

Federal Information Processing Standard (FIPS). In order to improve wireless LAN security

the 802.11i is considering inclusion of AES in WEPv2.

19

14 TEMPORAL KEY INTEGRITY PROTOCOL (TKIP)

The temporal key integrity protocol (TKIP), initially referred to as WEP2, is an interim

solution that fixes the key reuse problem of WEP, that is, periodically using the same key to

encrypt data. The TKIP process begins with a 128-bit "temporal key" shared among clients

and access points. TKIP combines the temporal key with the client's MAC address and then

adds a relatively large 16-octet initialization vector to produce the key that will encrypt the

data. This procedure ensures that each station uses different key streams to encrypt the data.

TKIP also prevents the passive snooping attack by hashing the IV.

TKIP uses RC4 to perform the encryption, which is the same as WEP. A major difference

from WEP, however, is that TKIP changes temporal keys every 10,000 packets. This

provides a dynamic distribution method that significantly enhances the security of the

network.

The Temporal Key Integrity Protocol is part of the IEEE 802.11i encryption standard for

wireless LANs. TKIP is the next generation of WEP, the Wired Equivalency Protocol, which

is used to secure 802.11 wireless LANs. TKIP provides per-packet key mixing, a message

integrity check and a re-keying mechanism, thus fixing the flaws of WEP.

FIG.13 TEMPORAL KEY INTEGRITY PROTOCOL

An advantage of using TKIP is that companies having existing WEP-based access points and

radio NICs can upgrade to TKIP through relatively simple firmware patches. In addition,

WEPonly equipment will still interoperate with TKIP-enabled devices using WEP. TKIP is a

temporary solution, and most experts believe that stronger encryption is still needed.

20

The temporal key integrity protocol (TKIP) which initially referred to as WEP2, was

designed to address all the known attacks and deficiencies in the WEP algorithm. According

to 802.11 Planet [6], the TKIP security process begins with a 128-bit temporal-key, which is

shared among clients and access points. TKIP combines the temporal key with the client

machine's MAC address and then adds a relatively large 16-octet initialization vector to

produce the key that will encrypt the data. Similar to WEP, TKIP also uses RC4 to perform

the encryption. However, TKIP changes temporal keys every 10,000 packets. This difference

provides a dynamic distribution method that significantly enhances the security of the

network. TKIP is seen as a method that can quickly overcome the weaknesses in WEP

security, especially the reuse of encryption keys. The following are four new algorithms and

their function that TKIP adds to WEP:

i. A cryptographic message integrity code, or MIC, called Michael, to defeat forgeries.

ii. A new IV sequencing discipline, to remove replay attacks from the attacker’s arsenal.

iii. A per-packet key mixing function, to de-correlate the public from weak keys.

iv. A re-keying mechanism, to provide fresh encryption and integrity keys, undoing the threat

of attacks stemming from key reuse.

15 TOOLS FOR PROTECTING WLAN

There are some products that can minimize the security threats of WLAN such as:

AirDefense It is a commercial wireless LAN intrusion protection and management system

that discovers network vulnerabilities, detects and protects a WLAN from intruders and

attacks, and assists in the management of a WLAN. AirDefense also has the capability to

discover vulnerabilities and threats in a WLAN such as rogue APs and ad hoc networks.

Apart from securing a WLAN from all the threats, it also provides a robust WLAN

management functionality that allows users to understand their network, monitor network

performance and enforce network policies [1].

Isomair Wireless Sentry This product from Isomair Ltd. automatically monitors the air

space of the enterprise continuously using unique and sophisticated analysis technology to

identify insecure access points, security threats and wireless network problems. This is a

dedicated appliance employing an Intelligent Conveyor Engine (ICE) to passively monitor

wireless networks for threats and inform the security managers when these occur. It is a

21

completely automated system, centrally managed, and will integrate seamlessly with existing

security infrastructure. No additional man-time is required to operate the system.

Wireless Security Auditor (WSA) It is an IBM research prototype of an 802.11 wireless

LAN security auditor, running on Linux on an iPAQ PDA (Personal Digital Assistant). WSA

helps network administrators to close any vulnerabilities by automatically audits a wireless

network for proper security configuration. While there are other 802.11 network analyzers

such as Ethereal, Sniffer and Wlandump, WSA aims at protocol experts who want to capture

wireless packets for detailed analysis. Moreover, it is intended for the more general audience

of network installers and administrators, who want a way to easily and quickly verify the

security configuration of their networks, without having to understand any of the details of

the 802.11 protocols.

16 CONCLUSION

22

The general idea of WLAN was basically to provide a wireless network infrastructure

comparable to the wired Ethernet networks in use. It has since evolved and is still currently

evolving very rapidly towards offering fast connection capabilities within larger areas.

However, this extension of physical boundaries provides expanded access to both authorized

and unauthorized users that make it inherently less secure than wired networks.

WLAN vulnerabilities are mainly caused by WEP as its security protocol.

However, these problems can be solved with the new standards, such as 802.11i, which is

planned to be released later this year. For the time being, WLAN users can protect their

networks by practicing the suggested actions that are mentioned in this paper based on the

cost and the level of security that they wish.

Wireless LAN security has a long way to go. Current Implementation of WEP has proved to

be flawed. Further initiatives to come up with a standard that is robust and provides adequate

security are urgently needed. The 802.1x and EAP are just mid points in a long journey. Till

new security standard for WLAN comes up third party and proprietary methods need to be

implemented.

While there are serious vulnerabilities when using WLANs. Taking certain precautions to

safeguard the confidentiality and integrity of your data can make your WLAN as safe as the

wired equivalent. Although these precautions may cost more effort and money, they are

necessary if you have an existing WLAN or intend to implement one. The 802.11 Tgi group

is working on new ways to replace WEP with schemes such as replacing the RC4 with AES

and adding sequence numbers to packets to prevent replay attacks. Until such schemes are

finalized and available as the 802.11i standard, there will be no complete fix for these

existing vulnerabilities. Like most advances, wireless LANs pose both opportunities and

risks. The technology can represent a powerful complement to an organization’s networking

capabilities, enabling increased employee productivity and reducing IT costs. To minimize

the attendant risks, IT administrators can implement a range of measures, including

establishment of wireless security policies and practices, as well as implementation of various

LAN design and implementation measures. Achieving this balance of opportunity and risk

allows enterprises to confidently implement wireless LANs and realize the benefits this

increasingly viable technology offers.

17 REFERENCES

Nikita Borisov, Ian Goldberg, and David Wagner, UC Berkeley, “Security of the WE

23

Algorithm,” (http://www.isaac.cs.berkeley.edu/isaac/wep-faq.html)

Wayne Caswell, “Wireless Home Networks: Disconnected Connectivity,” Home

Toys,

April 2000 (http://www.hometoys.com/mentors/caswell/apr00/wireless.htm)

Joel Conover, “Wireless LANs Work Their Magic,” Networking Computing, July

2000 (http://www.networkcomputing.com/1113/1113f2full.html)

Joel Conover, “First Things First—Top 10 Things to Know About Wireless,”

Networking Computing, July 2000

(http://www.networkcomputing.com/1113/1113f2side2.html)

John Cox, “LAN Services Set to Go Wireless,” Network World, August 20, 2001

(http://www.nwfusion.com/news/2001/0820wireless.html)

o Andy Dornan, “Emerging Technology: Wireless LAN Standards,” 2/6/02,

NetworkMagazine.com

(http://networkmagazine.com/article/NMG20020206S0006)

o Dale Gardner, “Wireless Insecurities,” Information Security magazine,

January 2002

(http://www.infosecuritymag.com/articles/january02/cover.shtml)

o IEEE Working Group for WLAN Standards

(http://grouper.ieee.org/groups/802/11/index.html)

o Dave Molta, “The Road Ahead for Wireless,” Network Computing, July 9,

2001

(http://www.networkcomputing.com/1214/1214colmolta.html)

Practically Networked, “Wireless Encryption Help”

(http://www.practicallynetworked.com/ support/wireless_encrypt.htm)

Practically Networked, “Securing Your Wireless Network”

(http://www.practicallynetworked.com/ support/wireless_secure.htm)

Practically Networked, “Mixing WEP Encryption Levels”

(http://www.practicallynetworked.com/ support/mixed_wep.htm)

Practically Networked, “Should I Use NetBeui?”

(http://www.practicallynetworked.com/ sharing/netbeui.htm)

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