I intend to write my CompTIA A+ Certification in the next few weeks. In preparation, I have come across some questions I can’t answer by my self. A few of the questions are Windows specific, so I will spare asking you folks these questions. I was hoping that you Ubuntu people could field some of my questions that are platform agnostic. Here they are:
1. My textbook claims, in the context of wireless device standards:
(Holcombe, 2012: 803)
Another issue is the standard supported by each device. If possible, for each wireless network installation, select NICs and WAPs that comply with the exact same Wi-Fi standard. Even though 802.11g, which is faster than 802.11b, is downward compatible with the slower standard, even a singly 802.11b device on the wireless network will slow down the entire WLAN.
If I connect my slow Kyocera RISE smartphone to my home WLAN, would that bring down/drag down all the download speeds of all the laptops? I’m not sure exactly what the Wi-Fi standard is of my smart phone device and I don’t know how fast my wireless router is, neither do I know what standard the laptops are on my WLAN. What I know for sure is that my cell is really slow (1Mbps down) and my laptops consistently download at 12Mbps. Accessing the WLAN with my cell doesn't slow down my laptops. What is my textbook referring to when it claims that 802.11b devices will slow down all the 802.11n devices connected to a network?
2. Let’s say I have 3 laptops on my home network with these IP addresses:
Are these addresses unique compared to all the other 4.2+ Billion devices on the global IPv4 internet? That can’t be true because 192.168.1.0 is a common ip address I have seen on many computers. How can every ip address assigned using a dhcpd service on the global internet be unique and yet devices on home networks be duplicated hundreds of thousands of times over and over, as in my example?
3. Are FTP/HTTP/IRC/BitTorrent protocols built on top of more basic protocols such as TCP/IP and UDP?
4. Practice review question # 3 for chapter # 1 says: “I plan to replace the power supply in a computer. What is the most important safety measure I should take to protect myself? The incorrect answer is to ground yourself by wearing an anti-static wrist band.” The correct answer is to NOT ground yourself. Why is that? Holcombe’s text on page 14 seems to contradict itself. The text book claims, “Touching a grounded portion of your computer’s chassis will work to some extent, but for complete safety, us an ESD wrist strap with a ground wire attached to the computer frame.” WTF? Is wearing an anti-static wrist strap a good idea or not?
5.Can you use a loopback plug to test whether or not a switch port is functioning? (Ch16Q#1)
Do you use nslookup as an alternative or substitute for a DHCP daemon to obtain an ip address for the localhost so it can access the internet? Could you furthermore use, ipconfig /renew as an alternative?
6. If a default gateway is down, I would think that I wouldn’t be able to communicate on LAN and access the internet, rather than only be able to access the global internet. (Ch15Q#13)