Understanding Wireless Networks
Quoting Wikipedia “A wireless network is a computer network that uses wireless data connections between network nodes.”
Computers are very often connected to networks using wireless links(WLANs), Our interest lies in how this connection is established.
For using these Wireless Networks, there is a standard which sets Rules and Regulations to use Wireless Networks for using Internet named as “IEEE 802.11”
In order to execute the WiFi
WEP (Wired Equivalent Privacy)
WPA (Wi-Fi Protected Access)
WPA2 (Wi-Fi Protected Access 2)
Wired Equivalent Privacy (WEP) was the first protection standard, introduced in 1997. By 2001, several serious weaknesses were identified so that today a WEP connection can be cracked within minutes, the main weakness of WEP is its use of static encryption keys. When you set up a router with a WEP encryption key, that key is used by every device on your network to encrypt every packet that’s transmitted. The WEP uses the RC4 algorithm and DES standard.
Wi-Fi Protected Access (WPA): To overcome the consequences of the attacks occurring in the WEP, WPA was introduced.WPA basically works with two scenarios one is with the Enterprise and the other is with the personal. WPA uses the temporal key integrity protocol (TKIP), which dynamically changes the key that the systems use making it difficult for a hacker to decrypt the key. Now this TKIP works with the Personal one when it comes with the other scenario i.e. WPA-Enterprise the authentication was done in the server side using the service called RADIUS(Remote Authentication Dial In User Service) and this Radius uses a protocol named as EAP (Extensible Authentication Protocol).
Wi-Fi Protected Access Pre-Shared Key (WPA-PSK): a security mechanism used to authenticate and validate users on a wireless LAN(WLAN) or Wi-Fi connection. It is a variation of the WPA security protocol. WPA-PSK is also known as WPA2-PSK or WPA Personal. It is a method of securing your network using WPA2 with the use of the optional Pre-Shared Key (PSK) authentication, which was designed for home users without an enterprise authentication server.
Wi-Fi Protected Access 2 (WPA2): As there was some difficulty in getting things done with the WPA thing i.e. it was not having that much effective security and it was not feasible for the normal person to get the RADIUS server implementation(that was more secure) ,hence WPA2 was introduced. This WPA2 basically uses AES(advanced encryption standard) encryption to protect classified information. It includes mandatory support for CCMP, an AES-based encryption mode.
WPA3(The later “SECURE”)
In January 2018, the Wi-Fi Alliance announced WPA3 as a replacement to WPA2. The major difference being the replacement of PSK(pre-shared key) with SAE(Simultaneous authentication of equals: based on Diffie–Hellman key exchange ).
HOW does authentication occur
,What is the 4-way handshake:
In Layman terms-
NOUNCE (Broadcast): Firstly a broadcast packet is sent by the AP(access point i.e our router) for all the clients in the vicinity known as ANounce for letting clients know that I, as an AP is available, this packet also consists the ESSID(name) and BSSID(mac address) of the router.
Reply of Nounce(unicast): On the client side, SNounce packet is sent to let the AP know that I as a client is available and want to connect to you, mac address of the client is shared in this step
Message of authentication(multicast):Then a packet consisting of message of authentication is sent by the AP to the client which wants to connect to the network. Stating the encryption protocols required to authenticate with the network, and the client is asked to enter the password.
Acknowledgement of authentication(unicast):The entered password is sent back to the router for authentication,If the password is correct, the authentication is acknowledged and connection is established.