Packet Tracer Tracer - Investigating the TCP/IP and OSI Models in Action Topology
Objectives Part 1 !"a#ine $TTP %eb Tra&&ic Part ' (isplay !le#ents o& the TCP/IP Protocol S)ite
*ackgro)nd This simulation activity is intended to provide a foundation for understanding the TCP/IP protocol suite and the relationship to the OSI model. Simulation mode allows you to view the data contents being sent across the network at each layer. s data moves through through the network! itit is broken down into smaller pieces pieces and identified identified so that the pieces pieces can be put back together when they arrive at the destination. "ach piece is assigned a specific name #protocol data unit $P%&'( and associated with a specific layer of the TCP/IP and OSI models. Packet Tracer simulation simulation mode enables you to view each of the layers and the associated P%&. The following following steps lead the user through the process of re)uesting a web page from a web server by using the web browser application available on a client PC. "ven though much of the information displayed will be discussed in more detail later! this this is an opportunity to e*plore the functionality of Packet Tracer and be able to visuali+e the encapsulation process.
Part Part 1 !"a# !"a#in ine e $TTP $TTP %eb %eb Tr Tra&&i a&&ic c In Part , of this activity! activity! you will use Packet Tracer #PT( Simulation mode to generate web traffic and e*amine -TTP.
Step 1 S+itch S+itch &ro# &ro# ,ealti#e ,ealti#e to Si#)l Si#)latio ation n #ode #ode In the lower right corner of the Packet Tracer interface are tabs to toggle between ,ealti#e and ,ealti#e and Si#)lation mode. PT always starts in ,ealti#e mode! ,ealti#e mode! in which n etworking protocols operate with realistic timings. -owever! a powerful feature of Packet Tracer Tracer allows the user to stop time by switching to Simulation mode. In Simulation mode! packets are displayed as animated envelopes! time is event driven! and the user can step through networking events. a. Click th the Si#)lation mode Si#)lation mode icon to switch from ,ealti#e mode ,ealti#e mode to Si#)lation mode. Si#)lation mode. b. Select $TTP from $TTP from the !vent .ist ilters. ilters . ,( -TTP may alread already y be the the only only visible visible event. event. Click Click !dit ilters to ilters to display the available visible events. Toggle the Sho+ All/0one check All/0one check bo* and notice how the che ck bo*es switch from unchecked to checked or checked to unchecked! depending on the current state.
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Packet Tracer - Investigating the TCP/IP and OSI Models in Action 1( Click the Sho+ All/0one check All/0one check bo* until all bo*es are cleared and then select $TTP. $TTP. Click anywhere outside of the !dit ilters bo* ilters bo* to hide it. The 4isible "vents should now only display -TTP.
Step Step ' 2ener 2enerate ate +eb +eb 3$TTP 3$TTP44 tra&&i tra&&ic c Currently the Simulation Panel is empty. There There are si* columns listed across the top of the "vent 5ist within the Simulation Panel. s traffic traffic is generated and stepped through! events appear in the list. The In&o column In&o column is used to inspect the contents of a particular event. 0ote6 0ote6 The 7eb Server and 7eb Client are displayed in the left pane. The panels can be ad8usted in si+e by hovering ne*t to the scroll bar and dragging left or right when the double9headed arrow appears. a. Click %eb Client in Client in the far left pane. b. Click th the (esktop tab and click the %eb *ro+ser icon icon to open it. c.
In the the &:5 &:5 fiel field! d! ente enterr +++osilocal and +++osilocal and click 2o. 2o. ;ecause time in Simulation mode is event9driven! you must use the Capt)re/or+ard button to display network events.
d. Click Capt)re/or+ard four times. There should be four events in the "vent 5ist. 5ook at the 7eb Client web browser page. %id anything change< The web page was returned from the web server.
Step 5 !"plore !"plore the contents contents o& the the $TTP $TTP packet packet a. Click Click the the first first color colored ed s)uare s)uare bo* bo* under under the !vent .ist = In&o column. In&o column. It may be necessary to e*pand the Si#)lation Panel or Panel or use the scrollbar directly below the !vent .ist. .ist. The P(6 In&or#ation at (evice %eb Client window Client window displays. In this window! there are only two tabs #OSI Model and Model and O)tbo)nd P(6 (etails( (etails ( because this is the start of the transmission. s s more events are e*amined! there will be three tabs displayed! adding a tab for Inbo)nd P(6 (etails. (etails . 7hen an event is the last event in the stream of traffic! only the OSI Model and Inbo)nd P(6 (etails tabs (etails tabs are displayed. b. "nsu "nsure re that that the the OSI Model tab Model tab is selected. &nder the O)t .ayers column! .ayers column! ensure that the .ayer 7 bo* 7 bo* is highlighted. 7hat is the te*t displayed ne*t to the .ayer 7 label< 7 label< -TTP 7hat information is listed in the n umbered steps directly below the In .ayers and .ayers and O)t .ayers bo*es< .ayers bo*es< ,. The -TTP client sends a -TTP re)uest to the server. c.
Click 0e"t .ayer . 5ayer > should be highlighted. 7hat is the (st Port value< Port value< ?2
d. Click 0e"t .ayer . 5ayer 3 should be highlighted. 7hat is the (est IP value< IP value< ,@1.,A?.,.1B> e. Click 0e"t .ayer . 7hat information is displayed at this layer< 5ayer 1 "thernet II -eader and inbound and outbound C addresses. f.
Click the O)tbo)nd P(6 (etails tab. (etails tab. Information listed under the P(6 (etails is (etails is reflective of the layers within the TCP/IP model. 0ote6 0ote 6 The information listed under the !thernet II section provides even more detailed information than is listed under 5ayer 1 on the OSI Model tab. Model tab. The O)tbo)nd P(6 (etails provides (etails provides more descriptive and detailed information. The values under (!ST MAC and MAC and S,C MAC within MAC within the !thernet II section of the P(6 (etails appear on the OSI Model tab Model tab under 5ayer 1! but are not identified as such.
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Packet Tracer - Investigating the TCP/IP and OSI Models in Action 7hat is the common information listed under the IP section of P(6 (etails as compared to the information listed under the OSI Model tab< 7ith which layer is it associated< S:C IP and %ST IP at 5ayer 3 7hat is the common information listed under the TCP section of P(6 (etails! (etails! as compared to the information listed under the OSI Model tab! and with which layer is it associated< S:C PO:T and %"ST PO:T at 5ayer > 7hat is the $ost listed $ost listed under the $TTP section of the P(6 (etails< (etails< 7hat layer would this information be associated with under the OSI Model tab< www.osi.local! 5ayer D g. Click Click the the ne*t ne*t colore colored d s)uare s)uare bo* bo* under under the the !vent .ist = In&o column. In&o column. Only 5ayer , is active #not grayed out(. The device is moving the frame from the buffer and placing it on to the network. h. dva dvanc nce e to to the the ne*t ne*t -TTP -TTP In&o bo* In&o bo* within the !vent .ist and click the colored s)uare bo*. This window contains both In .ayers and O)t .ayers. .ayers. Eotice the direction of the arrow directly under the In the In .ayers columnF it is pointing upward! indicating the direction the information is travelling. Scroll through these layers making note of the items previously viewed. t the top of the column the arrow points to the right. This denotes that the server is now sending the information back to the client. Comparing the information displayed in the In .ayers column .ayers column with that of the O)t .ayers column! .ayers column! what are the ma8or differences< The Src and %st Ports! Src and %st IPs and C addresses have been swapped. i.
Click the O)tbo)nd P(6 (etails tab. (etails tab. Scroll down to the $TTP section. $TTP section. 7hat is the first line in the -TTP message that displays< -TTP/,., 122 OG H this means that the re)uest was successful and the page p age delivered from the server.
8.
Click the last colored s)uare bo* under the In&o column. In&o column. -ow many tabs are displayed with this event and why< ust 1! one for the OSI odel and one for Inbound P%& %etails because this is the receiving device .
Part ' ' (ispla (isplay y !le#en !le#ents ts o& the the TCP/IP TCP/IP Protoc Protocol ol S)ite S)ite In Part 1 of this activity! activity! you will use the Packet Tracer Tracer Simulation mode to view and e*amine some of the other protocols comprising of the TCP/IP suite.
Step Step 1 1 8ie+ 8ie+ Addit Addition ional al !vent !vents s a. Close Close any any open open P%& info informa rmatio tion n window windows. s. b. In the "vent "vent 5ist 5ist Jilter Jilters s = 4isibl 4isible e "vents "vents section! section! click click Sho+ All. All . 7hat additional "vent Types are displayed< %epending on whether any communications has occurred prior to starting the original simulation! there should now be entries for :P! %ES! TCP and -TTP. It is possible that the :P entries may not show! depending on what a student may have done prior to going to simulation mode. If the activity is started from scratch all of those will be listed. These e*tra entries play various roles within the TCP/IP suite. If the ddress :esolution Protocol #:P( is listed! it searches C addresses. %ES is responsible for converting a name #for e*ample! +++osilocal( +++osilocal ( to an IP address. The additional TCP events are responsible for connecting! agreeing on communication parameters! and disconnecting the communications sessions between the devices. These protocols have been mentioned previously and will be further discussed as the course progresses. Currently there are over 3B possible protocols #event types( available for capture within Packet Tracer. c.
Click Click the the firs firstt %ES %ES event event in the the In&o column. In&o column. "*plore the OSI Model and Model and P(6 (etail tabs (etail tabs and note the encapsulation process. s you look at the OSI Model tab Model tab with .ayer 7 highlighted! 7 highlighted! a description of what is occurring is listed directly below the In .ayers and .ayers and O)t .ayers #,. .ayers #,. The %ES client sends a %ES )uery
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Packet Tracer - Investigating the TCP/IP and OSI Models in Action to the %ES server.(. This is very useful information to help understand what is occurring during the communication process. d. Click th the O)tbo)nd P(6 (etails tab. 7hat information is listed in the 0AM!6 0AM!6 in the %ES K&":L section< www.osi.local e. Clic Click k the the last last %ES %ES In&o colored In&o colored s)uare bo* in the event list. 7hich device is displayed< The 7eb Client 7hat is the value listed ne*t to A((,!SS6 A((,!SS6 in the %ES ES7": section of the Inbo)nd P(6 (etails< (etails < ,@1.,A?.,.1B> H the address of the 7eb Server f.
Jind the first $TTP event $TTP event in the list and click the colored s)uare bo* of the TCP event TCP event immediately following this event. -ighlight .ayer 9 in 9 in the OSI Model tab. Model tab. In the numbered list directly below the In .ayers and .ayers and O)t .ayers! .ayers! what is the information displayed under items > and B< >. The TCP connection is successful. B. The device sets the connection state to "ST;5IS-"%. TCP manages the connecting and disconnecting of the communications channel along with other responsibilities. This particular event shows that the communication channel has been "ST;5IS-"%. "ST;5IS-"%.
g. Click Click the last TCP event. event. -ighligh -ighlightt 5ayer 5ayer > in in the OSI Model tab. Model tab. "*amine the steps listed directly below In .ayers and O)t .ayers. .ayers. 7hat is the purpose of this event! based on the information provided in the last item in the list #should be item >(< C5OSIEM the connection.
Challenge This simulation provided an e*ample of a web session between a client and a server on a local area network #5E(. The client makes re)uests to specific services running on the server. The server must be set up to listen on specific ports for a client re)uest. #-int6 5ook at 5ayer > in the OSI Model tab Model tab for po rt information.( ;ased on the information that was inspected during the Packet Tracer capture! what port number is the %eb Server listening listening on for the web re)uest< The first -TTP P%& being re)uested by the 7eb Client shows port ?2 under the layer > %ST port. 7hat port is the %eb Server listening listening on for a %ES re)uest< The first %ES P%& being re)uested by the 7eb Client shows a layer > destination of port B3.
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Packet Tracer - Investigating the TCP/IP and OSI Models in Action
S)ggested Scoring ,)bric Activity Section Part Part ,6 ,6 "*ami "*amine ne -TTP -TTP 7eb Traffic
:)estion .ocation
Possible Points
Step 1d
B
Step 3b9,
B
Step 3b91
B
Step 3c
B
Step 3d
B
Step 3e
B
Step 3f9,
B
Step 3f91
B
Step 3f93
B
Step 3h
B
Step 3i
B
Step 38
B
Part 1 Total Part Part 16 %ispl %isplay ay "leme "lements nts of of the TCP/IP Protocol Suite
Challenge
;<
Step ,b
B
Step ,d
B
Step ,e9,
B
Step ,e91
B
Step ,f
B
Step ,g
B
Part ' Total
5<
,
B
1
B
Part 5 Total
1<
Total Score
1<<
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!arned Points
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