Write short notes after investigating the following scenarios :
a) 802.11a supports different modulation techniques, each allowing for different data rates. This adds complexity and cost to the radio, so your boss suggests 802.11zzz should only support one modulation technique, namely the maximum data rate possible. Do you support this idea? Why or why not?
b) Your company wants to provide wireless networking services in public places, such as in an airport lounge, where a wireless networking device detects multiple wireless networks with different SSIDs. What is the use of employing an SSID mechanism, state two reasons as to why it is necessary?
c) You company provides wireless networking services. One of your customers complains about the downloading performance being poor. After investigation, you find that the customer's 802.11 wireless network is interfering with his neighbour's wireless transfers. You want to improve performance, but you do not have any control over the neighbour's wireless connection (The only thing under your control is your customer's wireless router). Discuss the suitability of the following strategies in achieving better performance, e.g., under what conditions could it help, and when may it not be effective.
i. Frequency Assignment - Assigning a different channel to the user's wireless router.
ii. Power Control -- Lowering the transmit power of the user's wireless router.
iii. Enable RTS/CTS
2. Suppose a large office building has ESS WLAN for the office users. As a network engineer, you are asked to identify the drawbacks of the ESS WLAN with respect to roaming users. What would you recommend as a remedy to this drawback, if there any?
3. Explain how does the CSMA/CA in DCF handle media contention.
4. Suppose your company is going to provide services on broadb and wireless access networks. For this reason you are asked to perform a comparative study on different technologies of wireless broadband networks. You need to complete the following table based on your study (please replace Technology T with an appropriate technology similar to WiMAX and Wi-Fi, also add few additional features in place of Feature x, y and z):
|
Feature
|
WiMAX
|
Wi-Fi
|
Technology T
|
|
Frequency band
|
|
|
|
|
Channel bandwidth
|
|
|
|
|
Radio Technology
|
|
|
|
|
Half/Full Duplex
|
|
|
|
|
Modulation technique
|
|
|
|
|
Bandwidth Efficiency
|
|
|
|
|
Access protocol
|
|
|
|
|
Feature x
|
|
|
|
|
Feature y
|
|
|
|
|
Feature z
|
|
|
|
5. Define 'throughput' in regards to wireless network. Use a practical method (e.g., using an software) to measure throughput of a wireless network? You should provide any appropriate screenshots.
6. Suppose you work in a network security company, and you need to prepare a survey report of a particular security issue of wireless networking. To start with, select an area of wireless network security. We have listed some papers in the 'recommended reading/resources' part of the Subject Outline, which can be helpful in choosing a topic. You need to use more papers in your selected topic too. This project may be done in teams of 2-3 students. Active participation in the online meeting and on the Forum will help identify like minded team members. Please write all team members names and student IDs on the title page of report. You may choose to work on your own as well.
What is a survey?
The goal of a survey is to give a broad, structured overview of a specific area.
For example, suppose you are working for a company that is exploring a new wireless technology or market, so employees and management are very not very familiar with this new area. You could be asked to prepare a written report and a 30 minute presentation to introduce to area, highlighting different approaches, challenges, opportunities, and risks.
A survey is different from a set of paper summaries. The survey should focus on presenting the "big picture" using the papers as examples. For each topic, we have identified about three papers to get you started, but we generally expect that you will have to consult additional materials. Examples may be papers cited in the original papers, material found on the web, or results from online libraries, like IEEE Explorer, or the ACM portal.