WLAN cryptography

Security basics for wireless communication

The most important aspects of data communication are the data integrity and reliability. This mans data transfer 100 percent as desired. Data reaches the destination without any loss. The loss can be due to the data theft from hackers or intruders. One most common technique for the security of the data from adverse actions is cryptography.

Introduction to cryptography (Encryption / Decryption)

Cryptography is based on encryption and decryption. Encryption means to secure the signal through a code. This done through a specific algorithm. The algorithm is combined with the original data (known as plain text). This encrypted data is known as cipher text. The algorithm is known as the key. The same or some other algorithm or key is required to decrypt the data.

Types of key for encryption / decryption

I used the phrase some other key because of the fact that there are two types of keys. One is the private key cryptography (Symmetric) and other is public key cryptography (Asymmetric). In secret key cryptography same key is used to encrypt and decrypt data. The problem is that the sender has to send the key with the message to the receiver.

Public Key encryption / decryption

Public key encryption and decryption involves a key pair. A public key and a private key. Public is known to every one. Private key is personal for every one. Public key encrypts the data. Private key decrypts the data. So this eliminates the need to send the private key to other receivers. Asymmetric cryptography can also be used to secure webs servers. In such case you have to get a digital certificate.

Encryption / Decryption in Wireless LAN

Wireless LANs can be encrypted and decrypted through WPA (WiFi Protected Access). WPA is an improved extension for WEP (Wireless Equivalent Privacy). WLAN IEEE 802.11b standards can implement WEP security protocol. It was designed to offer the same security as found in wired LANs. It offers data protection from one end device to other end. The protocol works only at physical and data link layers of OSI model. So it cannot offer as much security for end-to-end communication as in wired LANs.

WPA (WiFi Protected Access)

To get rid the drawbacks of WEP, WPA was developed. The new products are based on WPA standard. It offers two improvements over WEP. One is TKIP (Temporal Key Integrity Protocol). Other is EAP (Extensible Authentication Protocol). TKIP improves the data encryption. It uses a hashing algorithm to scramble the keys. The result is the added integrity for the key protection. EAP is used for user authentication. It is based of public key encryption, preventing the unauthorized user access to the network.