Tightening Wireless Networks By Andrew Cohen

Question Why more and more businesses aren’t converting their wired networks into wireless networks?

The truth is that a wireless network “poses a much greater threat because the attacker has easy access to the transport medium. In wired networking, an attacker usually must penetrate some physical security perimeter to gain network access. But wireless networking’s broadcast nature makes traditional link-layer attacks readily available to anyone wishing to create mischief” (Arbaugh).

WiFi network A WiFi network, sometimes called Wireless Local Network (WLAN) consists of two main components; clients and access points – An access point is like a door to the wireless network. – A client is you… It utilizes radio waves for communication

Goals of Wireless Security Confidentiality Integrity Availability

A modern wireless router normally comes with several security features; Service Set Identifier, Wired Equivalent Privacy (WEP), and MAC Address Filters.

Service Set Identifier (SSID) It broadcasts the name of its wireless router to others who are searching for access points

Wired Equivalent Privacy (WEP) A technique dubbed RC4 stream cipher applies the 40 or 104 bit symmetric key to the data

MAC Address Filters hexadecimal value assigned to a piece of hardware

Secure Enough? Service Set Identifier Wired Equivalent Privacy (WEP) MAC Address Filters.

What do you need for hacking? cheap computer with a wireless LAN card to intercept the signal.

Hack SSID? Stumbling – actively detect networks Sniffing – capturing, all the traffic moving through the air

Hack MAC? ARP Spoofing (or ARP Poisoning) – It only requires a simple change in the operating system’s registry.

Hack WEP? WEP uses RC4 which takes short groups of data and expands it into an incredibly long random bunch of characters. Initialization Vector (IV) – only 24 bits long

How to improve WiFi security? Change default username and password Turn off SSID Enable MAC Filtering Turn on WEP Limit the # of clients (through DHCP) Change the default ip address ( )

Virtual Private Network (VPN) Intrusion Detection System (IDS) Temporal Key Integrity Protocol (TKIP) – a new encryption scheme WiFi Protected Access (WPA) – Wireless protocol Strong Password (over 20 characters) How to improve WiFi security?

802.11i protocol Incorporate all the advantages of WEP, WPA, AES, TKIP, and a few other encryption schemes.