8: 6 Wireless Networking Flashcards
Wi-Fi (802.11 standard)
Wireless standards on how wireless devices communicate with each other and access points.
How Wi-Fi works
Replaces network cables with radio transmitters and receivers- often connected to local networks that are connected to internet.
WAP
Wireless Access Points that connect wireless networks to wired networks and the internet
Different 802.11 standards
- 11 (1997) allows 2 Mbps
- 11b (1999) allows 11 Mbps
- 11g (2003) allows 22 Mbps
- 11n (2009) allows 600 Mbps
Wi-Fi security concern
Subject to undetectable interception.
WEP
Wired Equivalent Privacy - original encryption standard that is no longer considered secure
WPA
Wi-Fi protected access, replaced WEP in 2003 that used TKIP to add encryption keys, but now contains vulnerabilities.
WPA2
Version 2 that uses AES encryption standard that using the CCM protocol, widely used and considered secure.
WPA3
Version 3 that is now required on Wi-Fi devices from 2020 onward. Supports CCMP and uses SAE for key exchange.
3 mechanisms to authenticate a user of a wireless network
Pre-Shared keys, enterprise authentication, captive portals
Pre-Shared Keys
Simplest form of authentication, using an encryption key. Either a hexadecimal string or a password (password converted to a key)
Enterprise Authentication
Authorization server validates the credentials of the users. Uses version of EAP, like PEAP which uses TLS.
Secure versions of EAP
EAP TLS, EAP TTLS, EAP-Fast
Insecure versions of EAP
EAP MD5, LEAP
Captive Portals
Redirected to a webpage that can grant authentication (payment, accept terms of services)
Omnidirectional Antennas
Send signals in all directions
Directional Antennas
Direct all power from an access point in a single direction
Beamforming
Access point uses many antennas to steer the signal towards detected devices
Channels
Different wi-fi frequencies used to avoid interrupting overlapping wi-fi signals
Fat Access Point
Contain all hardware/software needed to operate a wireless network - can work independently or in coordination with other access points
Thin Access Points
Rely upon wireless controllers for configuration, dependent.
Wireless controllers
Manage configuration, optimize performance, reduce interface among APs
Wi-Fi analyzers
Search for rogue networks and test security
