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WIRELESS LAN SECURITY

Swagat Sourav

Wireless LAN Security

Presented By SWAGAT SOURAV Roll # EE 200118189

Under the guidance of

Mr. Siddhartha Bhusan Neelamani

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WIRELESS LAN SECURITY

Swagat Sourav

• It is also easy to interfere with wireless communications. A simple jamming transmitter can make communications impossible. For example, consistently hammering an access point with access requests, whether successful or not, will eventually exhaust its available radio frequency spectrum and knock it off the network.

• Advantages of WLAN

• Disadvantages WLAN

Introduction

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WIRELESS LAN SECURITY

Swagat Sourav

WLAN Authentication• Wireless LANs, because of their broadcast nature, require the addition of:

User authentication Data privacy • Authenticating wireless LAN clients.

Client Authentication Process

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WIRELESS LAN SECURITY

Swagat Sourav

WLAN Authentication• Types Of Authentication

Open Authentication

• The authentication request

• The authentication response Shared Key Authentication

• requires that the client configure a static WEP key

Service Set Identifier (SSID) MAC Address Authentication

• MAC address authentication verifies the client’s MAC address against a locally configured list of allowed addresses or against an external authentication server

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WIRELESS LAN SECURITY

Swagat Sourav

WLAN Authentication Vulnerabilities

• SSID

An eavesdropper can easily determine the SSID with the use of an 802.11 wireless LAN packet analyzer, like Sniffer Pro.

• Open Authentication

Open authentication provides no way for the access point to determine whether a client is valid.

• Shared Key Authentication Vulnerabilities

The process of exchanging the challenge text occurs over the wireless link and is vulnerable to a man-in-the-middle attack

• MAC Address Authentication Vulnerabilities

A protocol analyzer can be used to determine a valid MAC address

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WIRELESS LAN SECURITY

Swagat Sourav

WEP Encryption • WEP is based on the RC4 algorithm, which is a symmetric

key stream cipher. The encryption keys must match on both the client and the access point for frame exchanges to succeed

Stream Ciphers

Encrypts data by generating a key stream from the key and performing the XOR function on the key stream with the plain-text data

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WIRELESS LAN SECURITY

Swagat Sourav

WEP Encryption Block Ciphers

Fragments the frame into blocks of predetermined size and performs the XOR function on each block.

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WIRELESS LAN SECURITY

Swagat Sourav

WEP Encryption Weaknesses • There are two encryption techniques to overcome WEP encryption weakness

Initialization vectorsFeedback modes

• Initialization vectors

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WIRELESS LAN SECURITY

Swagat Sourav

WEP Encryption Weaknesses

• Feedback Modes

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WIRELESS LAN SECURITY

Swagat Sourav

WEP Encryption Weaknesses

• Statistical Key Derivation—Passive Network Attacks

A WEP key could be derived by passively collecting particular frames from a wireless LAN

• Inductive Key Derivation—Active Network Attacks

Inductive key derivation is the process of deriving a key by coercing information from the wireless LAN

Initialization Vector Replay Attacks

Bit-Flipping Attacks

• Static WEP Key Management Issues

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WIRELESS LAN SECURITY

Swagat Sourav

Component of WLAN Security

• The Authentication Framework (802.1X)

• The EAP Authentication Algorithm

Mutual Authentication

User-Based Authentication

Dynamic WEP Keys

• Data Privacy with TKIP (Temporal Key Integrity Protocol )

A message integrity check (MIC

Per-packet keying

Broadcast Key Rotation

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WIRELESS LAN SECURITY

Swagat Sourav

Future of WLAN Security• AES (Advanced Encryption Standard )

AES-OCB Mode

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WIRELESS LAN SECURITY

Swagat Sourav

Future of WLAN Security AES-CCM Mode

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WIRELESS LAN SECURITY

Swagat Sourav

ConclusionWireless LAN deployments should be made as secure as possible. Standard 802.11 security is weak and vulnerable to numerous network attacks. This paper has highlighted these vulnerabilities and described how it can be solved to create secure wireless LANs.

Some security enhancement features might not be deployable in some situations because of device limitations such as application specific devices (ASDs such as 802.11 phones capable of static WEP only) or mixed vendor environments. In such cases, it is important that the network administrator understand the potential WLAN security vulnerabilities.

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WIRELESS LAN SECURITY

Swagat Sourav

Thank You!!!