Reference no: EM133239595

Part 1: Measuring the digital bandwidth

Tasks to do:

Question 1. Describe shortly how you are connected to the Internet. You should provide information about the ISP providing your connection and the capacity (your upload and download speed). Details about the technology used and the basic principles of its operation should be provided, too.

Question 2. Download a file and measure the time for the download. You can use your own sites or the ones given below. Choose the file in such a way that you can measure the download time (larger if you have high speed Internet connection or smaller if you are using modem or other low speed connection.)

Question 3. Supply the following information. For the calculated values, explain how you have performed the calculations.
• URL for the file
• The size of the file (in bytes)
• The size of the file (in bits)
• The download time (in seconds)
• Calculated download speed for file transmission (bps)
• The capacity of your Internet connection (bps)
• Based on the last two values explain the relationship in magnitude between the download speed and the capacity of your Internet connection.

Question 4. Which are the layers in the TCP/IP protocol suite and how they relate to those in the OSI model?

Question 5. Distinguish between circuit-switching and packet-switching paradigm. Describe their differences and give examples of networks using one and the other type of switching.

Question 6. Open the page and read about the measurements available. Then choose one of them and answer the following questions:
• What kinds of measurements are available? Describe the services offered.
• Perform some measurements of interest to you. Explain what have you measured and what values you have obtained?

Part II: TCP/IP configuration

Tasks to do:

Question 1. Find the configuration of the TCP/IP stack on your computer. If you are using Windows, you can do that with the command ipconfig /all at the Command Prompt (Command prompt is in the group Accessories). You can also open the window Control Panel -> Network connections -> TCP/IP. If you are using Linux or any other UNIX flavored operating system, the command is ifconfig. Then fill in the following information.
• IP address (dotted decimal notation)
• IP address (binary form, 4 octets)
• Subnet mask (dotted decimal notation)
• Subnet mask (binary form, 4 octets)
• The number of 1s in the subnet mask
• Network part of the IP address (binary form)
• Host part of the IP address (binary form)
• Network address (binary form, 4 octets)
• Network address (dotted decimal notation)
• Broadcast address (binary form, 4 octets)
• Broadcast address (dotted decimal notation)
• Default gateway (dotted decimal notation)
• DNS server(s) (dotted decimal notation)
• The physical (MAC) address (in hexadecimal format)
• The physical (MAC) address (in binary form, 6 octets)

Question 2. In case you are using DHCP try to return the IP address and to renew it again. You can return the IP address back to the DHCP server by using the command ipconfig /release at the command prompt. You can obtain (renew) the address using ipconfig /renew. Try these commands and explain what happened.

Question 3. Find some information about private IP addresses. You can use RFC 1918 or search using the search engine www.google.com. Write a paragraph about private IP addresses (what they are, when they are used and the range of IP addresses). Explain the difference between private and public addresses and the purpose of NAT (Network Address Translation).

Part III: Simple tools for troubleshooting TCP/IP network

Tasks to do:
Question 1. Open the command prompt window and give the command "ping -n 5 www.freebsd.org". Answer the following questions.
• What is the effect of the argument -n 5 on the ping program?
• What is the average value of the RTT you have obtained? Explain how was it calculated?
• What is the meaning of the acronym TTL and why is it used? (Search the Internet to find out.) What is the value of TTL you have obtained?

Question 2. Use the traceroute program to find the path to a destination of your choice. After you have obtained the output, supply the following information.
• Destination address
• Number of hops
• IP addresses of the five nodes where there is the maximum delay and the delay experienced on these hops.
• Perform the traceroute to the same destination at another day and time. Check whether there exist any changes. Explain possible reasons for the appearance of some differences.

Question 3. Use nslookup or one of the web sites that provide DNS lookup to find out the IP address for a domain name of your choice. Supply the following information.
• The domain name of the DNS server you have used
• The domain name for which you have searched the IP address
• The IP address obtained
• Explanation how DNS works and the reasons it uses a distributed database instead of a centralized one.

Question 4. Use netstat -rn to display the forwarding (routing) table for your computer on the screen. Show the forwarding table and explain the meaning of each row in the table.

Question 5. Use the command netstat /? to explore the parameters that can be used with it. Then use netstat -n -a to display all connections and listening port. Choose one of the established connections and supply the following information:
• Transport protocol
• Local address and port number
• Remote address and port number
• What command should be issued (netstat and which parameter) in order to get the process ID (PID) for the connection.

Attachment:- Measuring the digital bandwidth.rar