Sim-Ex™ Lab Simulator for Network+ : Lab Exercises

Matching the 802.11 Standards With Respective Speeds

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Description: This lab exercise helps you to know the speed ranges of a 802.11 standards.

Instructions :

1. Different 802.11 standards are given in the column A

2. Various speed ranges of 802.11 standards are given in the column B

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3. Match (drag and drop) the standards given on the column A with their speed ranges given on the column B.

Explanation:

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The following are the important features of 802.11 standards:

1. IEEE 802.11: Standard for wireless LANs

2. The hardware costs are more for 802.11b compared with 802.11g, and the standard is not yet well established.

3. The 802.11g standard supports data rates up to 54 Mbps, whereas 802.11b supports data rates only up to 11 Mbps.

4. The hardware complying to 802.11g operates at 2.4 GHz range

5. The 802.11g equipment is as susceptible to interference as 802.11b.

6. IEEE 802.11g is compatible with 802.11b, but not compatible with 802.11a, or Bluetooth.

7. 802.11n works in both 2.4GHz, and 5GHz bands. The standard supports up to 600Mbits/sec bandwidths. It is downward compatible with 802.11a, 802.11b, and 802.11g standards.

8. 802.11a, and 802.11g use OFDM (short for Orthogonal Frequency Division Multiplexing). IEEE 802.11b uses DSSS (short for Direct Sequence Spread Spectrum) for encoding.

9. 802.11ac : The emerging Wi-Fi signaling standard, 802.11ac utilizes 5GHz channel. 802.11ac offers backward compatibility to 802.11b/g/n and bandwidth rated up to 6.9 Gbps at 5 GHz band. The speed is theoretical maximum and actual speeds will depend on several factors, like number of antennas, channel bandwidth, etc. For 160MHz channel, the speed is 867 Mbit/s, and 802.11ac can have up to 8 antennas at 160MHz channel, delivering 6.9Gbits/sec speed, theoretically.

The data rates supported by various wireless standards are as given below:

  • Bluetooth: Up to 1 Mbps
  • 802.11a: Up to 54 Mbps
  • 802.11b: Up to 11 Mbps
  • 802.11g: Up to 54 Mbps
  • 802.11ac Up to 6.9Gbps

As shown above, Bluetooth has the lowest data rates, whereas 802.11a, and 802.11g support data rates up to 54 Mbps.

Important Points to Remember:

  • IEEE 802.11b uses DSSS (short for Direct Sequence Spread Spectrum) for encoding.
  • Also note that 802.11a, and 802.11g use OFDM (short for Orthogonal Frequency Division Multiplexing).
  • 802.11 standards are typically used in wireless LAN configurations. Bluetooth supports low speeds up to 1 Mbps over short distances up to a max of 30 feet. The technology is well suited for connecting PDAs or wireless mouse to a computer.
  • 802.11g is compatible with 802.11b. Note that 802.11b is not compatible with either 802.11a or 802.11g. Similarly, 802.11a is not compatible with either 802.11b or 802.11g. Therefore, from compatibility point of view, 802.11g has better compatibility.
  • 802.11g has a maximum bit rate of 54Mbps and uses OFDM for modulation. Note that 802.11a also has the maximum bit rate of 54Mbps, but works in 5GHz frequency band.
  • To connect your notebook computer to a wireless network. The network interface card (NIC) required to connect to a 54 Mbps wireless LAN that uses 2.4GHz frequencies as per the Wi-Fi standard is 802.11g standard.
  • All Bluetooth, 802.11b, and 802.11g use 2.4GHz spectrum, where as 802.11a uses 5 GHz spectrum. Note that 2.4GHz band is more susceptible to noise compared with 5 GHz because several ISM band compatible devices work in the 2.4GHz frequency band.
  • IEEE 802.3 defines the MAC layer for bus networks that use CSMA/CD. This is the basis of the Ethernet standard.
  • Bluetooth is a standard for the short-range wireless interconnection of mobile phones, computers, and other electronic devices.
  • Rendezvous, based on open Internet Engineering Task Force (IETF), uses standard networking protocols and zero configuration technology to automatically discover and connect devices over any IP network, such as Ethernet or 802.11-based wireless networks like Apple's Airport.
  • IEEE 802.11x is the standard that pertains to wireless LANs.
  • 802.11ac is called Gigabit Wi-Fi or 5G Wi-Fi. It is a 5-GHz only technology that can use wider channels in the 5-GHz band, more spatial streams, and multi-user MIMO (MUMIMO). 
  • IEEE 802.1 : Standards for LAN/MAN bridging and management and remote media access control (MAC) bridging.
  • IEEE 802.10 : Standards for LAN/MAN security implementations. 
  • IEEE 802.16 : Wireless Networking - "WiMAX" 

Worldwide Interoperability for Microwave Access (WiMAX) is based on 802.16.

  • IEEE 802.11 : Wireless LAN (WLAN) and Mesh (Wi-Fi certification)
  • IEEE 802.14 : Cable modems
  • IEEE 802.15 : Wireless PAN

IEEE 1905.1-2013: This focuses on an abstraction layer that can allow for multiple home networking technologies to use a common interface. That abstraction layer can then support a dynamic interface capable of transmitting packets arriving from any upper protocol layers or underlying network technologies.

  • IEEE 802.16 : Wireless Networking - "WiMAX"
  • IEEE 802.15.1 : Bluetooth
  • IEEE 802.14 : Standards for cable television broadband communications.

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