Basic Networking Tools Study Week #1

Week #1: Basic Networking Tools

• Wireshark, Tcpdump, Ping, Traceroute, and Nmap are essential networking tools to understand.
• The lab manual is written for Ubuntu Linux OS only, and experiments can be executed on VirtualBox or VMWare platforms.

Linux Interface Configuration (ifconfig/IP command)

• ifconfig or ip addr show displays the status of all active network interfaces.
• Assign an IP address to an interface using sudo ifconfig interface_name 10.0.your_section.your_sno netmask 255.255.255.0 or sudo ip addr add 10.0.your_section.your_sno /24 dev interface_name.
• Activate/deactivate a network interface using sudo ifconfig interface_name down and sudo ifconfig interface_name up.
• Show the current neighbor table in the kernel using ip neigh.

Ping PDU (Packet Data Units or Packets) Capture

• Assign an IP address to the system (Host) using sudo ifconfig interface_name 10.0.your_section.your_sno netmask 255.255.255.0.
• Launch Wireshark and select the 'any' interface.
• Analyze the TTL, protocol used by ping, and time in the terminal.
• Analyze the frames with the first echo request and echo reply in Wireshark.

HTTP PDU Capture Using Wireshark's Filter feature

• Launch Wireshark and select the 'any' interface.
• Filter HTTP packets using http in the filter toolbar.
• Analyze the first and second frames (interaction of host to the web server and response of server to the client).
• Analyze the HTTP request and response using Wireshark's Follow TCP Stream.

Capturing packets with Tcpdump

• Use tcpdump -D to see available interfaces for capture.
• Capture all packets in any interface using sudo tcpdump -i any.
• Perform some pinging operation while capturing packets.
• Filter packets based on protocol using sudo tcpdump -i any -c5 icmp.
• Save packets to a file using sudo tcpdump -i any -c10 -nn -w webserver.pcap port 80.

Perform Traceroute checks

• Run the traceroute using sudo traceroute www.google.com.
• Analyze the destination address of google.com and the number of hops.
• Use the -n option to disable the mapping of IP addresses with hostnames.
• Use the -I option to use ICMP packets.
• Use the -T flag to test a TCP connection.

Explore an entire network for information (Nmap)

• Scan a host using its hostname or IP address using nmap www.pes.edu or nmap 163.53.78.128.
• Scan multiple IP addresses or subnets using nmap 192.168.1.1 192.168.1.2 192.168.1.3.

Submission Guidelines

• Take screenshots of results after execution of every command in every task.
• Write the task and 2-3 lines of observation followed by screenshots.
• Submissions will be through Google Forms.