Wireless LANs
Wireless LAN Standards
- WiFi 802.11
- B / A / G / N / AC / AX / I
- B is 2.4 Ghz / A is 5 Ghz / G is 2.4-5 Ghz with backwards compatibility / N is muilti-in multi-out / AC is 5 Ghz / AX is our latest and greatest today / I is a standard for wireless security.
- Backwards compatibility
- Older equipment might be able to join the network at a limited speed probably.
- Discrete components or combined.
- Upgrade them easily
- 2.4 GHz & 5 GHz
- 2.4 GHz is older and has more competing devices, they may interference or bother in communications of 2.4.
- As the frequency goes up, the wavelength decreases (Chemistry). So 2.4 GHz has certainly some benefits.
- Scalable
- We can do meshing to make wireless networks large
Wireless LAN Components
- Wireless Access Point (WAP)
- This is also called a bridge. Think of layer 2 forwarding, dealing with radio frequencies on one side and ethernet on the other side.
- WAPs would be Autonomous vs Controlled
- Autonomous means that we manage each one individually, each one has an IP, and each one has its own config, the downside about that is keeping all my configs the same everywhere, keeping all my firmware the same everywhere
- In Controlled mode you could have hundreds or thousands of access points, and they all call home to a mothership which is the WLC.
- Wireless LAN Controller (WLC)
- Central repository for the config of the WAPs
- This is where we deliver bin images of your firmware.
- So everyone's running the same firmware, the same config. We change on that WLC and it will change on all WAPs.
Wireless Antennas
Antenna types
- Directional
- Omnidirectional
- Indoor
- Outdoor
- Frequency
- 2.4 GHz
- 5 GHz
- 6E = 6 GHz
- You may see access points with 4 antennas where 2 of them are 2.4 GHz and the other 2 are 5 GHz.