Private keys, which are different from public keys, are only available (although not transmitted directly, used in a mathematical calculation) to the intended recipient. These keys are used to decrypt the message.
The methods used to secure a wireless network are WiFi Protected Access (WPA) and WiFi Protected Access II (WPA2).
WPA2 replaced WPA. WPA2 uses AES (Advanced Encryption Standard) to secure data. In AES, for every data packet, a new 128-bit key is generated.
Each network is identified by a 32-character code called Service Set Identifier (SSID).
A computer may be within range of several wireless networks and SSID helps us to identify the correct network. SSIDs are locally unique. Wireless networks are protected with passwords or security keys which is an identifier of up to 32 bytes.