Download - Review of TCP- IP CS105 Norwalk CC
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Principles of TCP/IP
DescriptionThe purpose of this lesson is to explain the concept of a
protocol stack and the basic functions of TCP/IP by using a postal example. This lesson is aimed at middle school or high school students who do not have a background in network protocols
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Overview
PurposeThe purpose of this lesson is to explain the concept of a protocol stack and the basic
functions of TCP/IP by using a postal exampleLesson Objectives• Student will, when presented a scenario, identify which activities are accomplished by
IP, TCP, and upper level protocols.• Student will be use the correct vocabulary when discussing data communications
related to the protocol stack and TCP/IP.• Student will be able to describe the difference in how the physical address and the IP
address is used in moving traffic from one node to another on the internet.• Student will be able to use the Web as a tool to research networking topicsTarget Population• This lesson is aimed at middle school or high school students who do not have a
background in network protocolsDuration• 45 minutes with lab and exercisesSupplies and Equipment• Machine to display PowerPoint presentation.• PC with internet access for use in tracing internet traffic, ping, and running ipconfig.
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Communications ProtocolsOn step at a time
A communications protocol is a collection of all the steps required for two entities to communicate separated into logical layers.
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A Communications ProtocolA Letter to a Friend
When we communicate with a friend using the mail, we are using an informal communications protocol
We combine each of the layers into a stack.
Write letter
Place in envelope labeled with sender’s return address and the recipient’s address
Request mail receipt
Place in mailbox
Read letter
Recipient verifies the letter is addressed to him/her and checks to see who sent it
Return mail receipt
Retrieve from mailbox
Magical mail Transporter
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A Communications ProtocolA Letter to a Friend
When we communicate with a friend using the mail, we are using an informal communications protocol
We combine each of the layers into a stack.
Write letter
Place in envelope labeled with sender’s return address and the recipient’s address
Request mail receipt
Place in mailbox
Read letter
Recipient verifies the letter is addressed to him/her and checks to see who sent it
Return mail receipt
Retrieve from mailbox
Magical mail Transporter
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A Communications ProtocolEach layer has a “friend” at the other end
Layers in the sending stack have corresponding layers in the receiving stack.
Write letter
Place in envelope labeled with sender’s return address and the recipient’s address
Request mail receipt
Place in mailbox
Read letter
Recipient verifies the letter is addressed to him/her and checks to see who sent it
Return mail receipt
Retrieve from mailbox
If we write a letterIt must be read
If we put it in an envelope it must be removed
Magical mail Transporter
Two way communications only at this level
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Simplified Protocol StackOverview
• This is a simplified protocol stack, similar to the stack used in TCP/IP, the way most computers communicate across the internet.
• The purpose of this model is to get a general understanding of the purpose of a protocol stack. This will prepare us to explore the complexity of TCP/IP in depth.
Transport(TCP plus others)
InternetIP plus others
Network
Upper Level ProtocolsWord, Explorer,
HTTP, FTP
Windows
Write the letterRead the letter
Put the letter in an envelope, address it, and mail it
Post Office activities
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Simplified Protocol StackUpper Level Protocols
Transport(TCP plus others)
InternetIP plus others
Network
Upper Level ProtocolsWord, Explorer,
HTTP, FTP
Windows
The various programs on our computer that:
• We use to create and save files, browse the Web, send email, etc.
• Interface these programs to the communications protocols as streams of data
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Simplified Protocol StackTransport Layer
Host-to-host communications that provide for • Communication between the sending
and receiving computers, regardless of the intermediate steps required to move the message
• An end-to-end handshake advising the sending host that the message was received
• Flow control to ensure that the recipient isn’t overwhelmed by incoming traffic
• Reassembling of incoming messages if they were broken up to make them small enough to transport
Transport(TCP plus others)
InternetIP plus others
Network
Upper Level ProtocolsWord, Explorer,
HTTP, FTP
Windows
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A Communications ProtocolMoving the mail
• Mail is moved from address to address (physical locations).
• On the way between these addresses it will transit some intermediate nodes (such as our mail carrier’s van)
Magical Mail Transporter
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A Communications ProtocolInternet (Virtual Address) Layer
Magical Mail Transporter
#32 Second Street Friendstown, NJ
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Simplified Protocol StackInternet Layer
Network to network communications
• Passes the message from
network to network toward its
destination
• Knows if it successfully passes
the message to the next
network
• Does not know if the message
goes any further
Transport(TCP plus others)
InternetIP plus others
Network
Upper Level ProtocolsWord, Explorer,
HTTP, FTP
Windows
153.123.234.128
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A Communications ProtocolNetwork (Physical Device) Layer
Magical Mail Transporter
I got the letter from the mailbox and put it in my truck
The letter was unloaded from the truck and put in the main post office.
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Simplified Protocol StackNetwork Layer
Node to node communications
• Passes the message to the next
hardware device in the path
• Actually “puts the signal on the wire”
• Knows if it successfully passes the
message to the next device
• Doesn’t know if the message goes
any further
Transport(TCP plus others)
InternetIP plus others
Network
Upper Level ProtocolsWord, Explorer,
HTTP, FTP
Windows
00-04-23-8B-A3-8D
00-03-A4-7C-B3-AD
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Segment and Packet Wrappers
• AI– Show shell of TCP Segment and IP Packet wrappers and relate to parts of the
address on an envelope where reasonable
– Discuss the concept of a port as a requirement for complete addressing (analog-the recipient’s name)
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Tracing your connection
Use the tracert command to see the path traffic might take from your PC to a receiving host
1. Open the command prompt on your PCStart ->Programs ->Accessories -> Command Prompt
2. Enter the tracert command, using the domain name of a site that you visit frequently (such as Google) as the argument
tracert Google.com
3. The path is displayed in the command window.
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Finding a host IP address and tracing
1. Look up the ping command using the Web.Record its purpose and how to use it
2. Ping the site you used when you ran the tracertcommand
3. Record the IP address that replies.This is the IP address of the receiving host.
4. Run tracert, using the IP address as the argument instead of the domain name
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Finding your IP address and MAC Address
Use the ipconfig/all command to see the IP Address and MAC Address of the machine you are using
1. Open the command prompt on your PCStart ->Programs ->Accessories -> Command Prompt
2. Enter the ipconfig/all command ipconfig/all
3. Read off 1. Your IP Address
2. Your MAC Address(it is called the Physical Address in the results)
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Research Activity
Complete the following table, in your own words
Term Description How I would use it
tracert
ipconfig
ping