4. Wireshark is a network packet/protocol analyzer.
◦ A network packet analyzer will try to capture network packets
and display packet data details.
The basic tool for observing the messages exchanged
between executing protocol entities is called a packet
sniffer.
Prepared by: Engr. Syed Abdul Basit
15. MRTG is a tool to monitors and measures the traffic
load on network links (web server, router).
MRTG generates HTML pages containing graphs
which provide a LIVE visual representation of the
traffic.
Typically collects data every five minutes.
Prepared by: Engr. Syed Abdul Basit
16. MRTG uses the Simple Network Management
Protocol (SNMP) to send requests.
MRTG consists of a Perl script which uses SNMP to
read the traffic counters of the routers.
Prepared by: Engr. Syed Abdul Basit
20. Comprehensive networking technology teaching and
learning software with powerful simulation,
visualization, assessment, and collaboration
capabilities.
To know more about:
http://www.cisco.com/web/learning/netacad/packet_tracer/packet_tracer_03-
4_web.html
Prepared by: Engr. Syed Abdul Basit
21. simulate IOS commands
visualize network traffic
collaborate on multiuser activities
Prepared by: Engr. Syed Abdul Basit
22. Anyone can author, the PT
Activity Wizard guides you.
The process is basically write
instructions, build a correct
answer network, specify
grading, specify an initial
network, save.
Ability to create your own
learning activities, tasks, labs,
games and complex
assessments.
Build learning experiences,
formative and summative
assessments.
Prepared by: Engr. Syed Abdul Basit
24. Logical & Physical Real-Time and
User friendly CLI
Workspaces Simulation Modes
LAN, switching,
Global event list TCP/IP, routing, Multiple platform
(packet sniffer) and WAN support
protocols
Activity Wizard, Integrated Help
Lab grading and Tutorials
Prepared by: Engr. Syed Abdul Basit
25. PT 5.0 is now a network-capable (peer to peer) application,
using the real network (TCP socket connections) to carry the
Packet Tracer virtual packets.
The PT application running on one computer can
communicate with the PT application running on 1 or more
other computers.
This connectivity between multiple instances of PT supports
teamwork, classroom games, collaboration, competition,
remote instructor-student interaction, and social networking.
Prepared by: Engr. Syed Abdul Basit
26. 3 Packet Tracer instances interacting
via Packet Tracer Messaging Protocol (PTMP)
Real TCP
Socket
Connection
PC 1 PC 2
Real TCP Real TCP
Socket Socket
Connection Connection
PC 3
Prepared by: Engr. Syed Abdul Basit
27. Access the global instructor community for questions, discussions,
collaboration, and activity sharing
Prepared by: Engr. Syed Abdul Basit
28. These are not listed on the PT Resource Page:
PT Help Contents
PT embedded Tutorials
Prepared by: Engr. Syed Abdul Basit
33. Syed Abdul Basit
+92 334 354 9727
sabasit2006@gmail.com
Join me on Social Media
http://xeesm.com/SyedAbdulBasit/
Notas del editor
Figure 1 shows the structure of a packet sniffer. At the right of Figure 1 are the protocols (in this case, Internet protocols) and applications (such as a web browser or ftp client) that normally run on your computer. The packet sniffer, shown within the dashed rectangle in Figure 1 is an addition to the usual software in your computer, and consists of two parts. The packet capture library receives a copy of every link-layer frame that is sent from or received by your computer. Recall from the discussion from section 1.5 in the text (Figure 1.202) that messages exchanged by higher layer protocols such as HTTP, FTP, TCP, UDP, DNS, or IP all are eventually encapsulated in link-layer frames that are transmitted over physical media such as an Ethernet cable. In Figure 1, the assumed physical media is an Ethernet, and so all upper layer protocols are eventually encapsulated within an Ethernet frame. Capturing all link-layer frames thus gives you all messages sent/received from/by all protocols and applications executing in your computer. The second component of a packet sniffer is the packet analyzer, which displays the contents of all fields within a protocol message. 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 text.