Wireless Networking

Wireless Networking

1. Wireless transmission

   • uses radio waves for communication

2. Wireless NICs

   • built into every networked device capable of connecting to a wireless network

3. Wireless access point

   • allows wireless devices to connect to a wired network using Wi-Fi
   • the AP usually connects to a router (via a wired network) as a standalone device
     • can also be an integral component of the router itself

4. Wifi Frequencies and channels

   • the 802. 11 standard uses five frequencies
     • each frequency is subdivided into various channels
       • each channel has a central frequency and bandwidth
     • 2.4GHz frequency
       • advantages
         • greater range and coverage
       • disadvantages
         • more interference from other devices and only three non overlapping channels
     • 5GHz frequency
       • disadvantages
         • fewer devices can use the 5GHz frequency, less able to penetrate through walls
       • advantages
         • less crowded space with 23 non overlapping channels with higher data transmission rates

5. data that is transmitted over a network can be intercerpted

   • data can be encrypted to stop this

6. encryption terminology

   • plain text: the original message to be encrypted
   • ciphertext: the encrypted mesasage
   • encryption: the process of converting plain text into cipher text
     • encryption algorithm: the formula for encrypting the plaintext
   • key: a sequence of numbers used to encrypt or decrypt, often data using a mathematical formula