Nt1310 Unit 3 Assignment 1
Wireshark Lab: Getting Started
Version: 2.0 © 2007 J.F. Kurose, K.W. Ross. All Rights Reserved
Computer Networking: A Topth down Approach, 4 edition.
“Tell me and I forget. Show me and I remember. Involve me and I understand.” Chinese proverb One’s understanding of network protocols can often be greatly deepened by “seeing protocols in action” and by “playing around with protocols” – observing the sequence of messages exchanged between two protocol entities, delving down into the details of protocol operation, and causing protocols to perform certain actions and then observing these actions and their consequences. This can be done in simulated scenarios or in a “real” network environment such as the Internet. The Java applets that …show more content…
In order to do so, the packet analyzer must “understand” the structure of all messages exchanged by protocols. For example, suppose we are interested in displaying the various fields in messages exchanged by the HTTP protocol in Figure 1. The packet analyzer understands the format of Ethernet frames, and so can identify the IP datagram within an Ethernet frame. It also understands the IP datagram format, so that it can extract the TCP segment within the IP datagram. Finally, it understands the TCP segment structure, so it can extract the HTTP message contained in the TCP segment. Finally, it understands the HTTP protocol and so, for example, knows that the first bytes of an HTTP message will contain the string “GET,” “POST,” or “HEAD,” as shown in Figure 2.8 in the …show more content…
We’ll assume that your computer is connected to the Internet via a wired Ethernet interface. Do the following 1. Start up your favorite web browser, which will display your selected homepage. 2. Start up the Wireshark software. You will initially see a window similar to that shown in Figure 2, except that no packet data will be displayed in the packetlisting, packet-header, or packet-contents window, since Wireshark has not yet begun capturing packets. 3. To begin packet capture, select the Capture pull down menu and select Options. This will cause the “Wireshark: Capture Options” window to be displayed, as shown in Figure
Version: 2.0 © 2007 J.F. Kurose, K.W. Ross. All Rights Reserved
Computer Networking: A Topth down Approach, 4 edition.
“Tell me and I forget. Show me and I remember. Involve me and I understand.” Chinese proverb One’s understanding of network protocols can often be greatly deepened by “seeing protocols in action” and by “playing around with protocols” – observing the sequence of messages exchanged between two protocol entities, delving down into the details of protocol operation, and causing protocols to perform certain actions and then observing these actions and their consequences. This can be done in simulated scenarios or in a “real” network environment such as the Internet. The Java applets that …show more content…
In order to do so, the packet analyzer must “understand” the structure of all messages exchanged by protocols. For example, suppose we are interested in displaying the various fields in messages exchanged by the HTTP protocol in Figure 1. The packet analyzer understands the format of Ethernet frames, and so can identify the IP datagram within an Ethernet frame. It also understands the IP datagram format, so that it can extract the TCP segment within the IP datagram. Finally, it understands the TCP segment structure, so it can extract the HTTP message contained in the TCP segment. Finally, it understands the HTTP protocol and so, for example, knows that the first bytes of an HTTP message will contain the string “GET,” “POST,” or “HEAD,” as shown in Figure 2.8 in the …show more content…
We’ll assume that your computer is connected to the Internet via a wired Ethernet interface. Do the following 1. Start up your favorite web browser, which will display your selected homepage. 2. Start up the Wireshark software. You will initially see a window similar to that shown in Figure 2, except that no packet data will be displayed in the packetlisting, packet-header, or packet-contents window, since Wireshark has not yet begun capturing packets. 3. To begin packet capture, select the Capture pull down menu and select Options. This will cause the “Wireshark: Capture Options” window to be displayed, as shown in Figure