NG01d The OSI Seven-Layer Network Model
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Review Questions. Answers appear at the end of this document.

What is the name of each  layer of the OSI 7-Layer Model?

	1.	Layer 1	_____________

	2.	Layer 2	_____________

	3.	Layer 3	_____________

	4.	Layer 4	_____________

	5.	Layer 5	_____________

	6.	Layer 6	_____________

	7.	Layer 7	_____________

Give an example of a protocol used in each layer of the OSI 7-Layer Model:

	8.	Application	_____________

	9.	Data Link	_____________

	10.	Network	_____________

	11.	Physical	_____________

	12.	Presentation	_____________

	13.	Session	_____________

	14.	Transport	_____________

Give an example of a protocol used in each layer of the OSI 7-Layer Model:

	15.	Layer 1	_____________

	16.	Layer 2	_____________

	17.	Layer 3	_____________

	18.	Layer 4	_____________

	19.	Layer 5	_____________

	20.	Layer 6	_____________

	21.	Layer 7	_____________

22.	In the OSI 7-Layer Model, what is the function of the Application layer?


23.	In the OSI 7-Layer Model, what is the function of the Data Link layer?


24.	In the OSI 7-Layer Model, what is the function of the Network layer?


25.	In the OSI 7-Layer Model, what is the function of the Physical layer?


26.	In the OSI 7-Layer Model, what is the function of the Presentation layer?


27.	In the OSI 7-Layer Model, what is the function of the Session layer?


28.	In the OSI 7-Layer Model, what is the function of the Transport layer?





ANSWERS

Answers to questions 1-21:
1. Physical: Wire (CAT 1, CAT 5, ISDN, ADSL, ATM); Fiber (FDDI); Wireless (TDMA, CDMA, Bluetooth, 
IRDA)
2. Data Link: Ethernet, SLIP, PPP
3. Network: IP (versions 4 or 6), IPX (Novell)
4. Transport: TCP, UDP
5. Session: "Ports" such as: 25 for incoming mail, 80 for Web, 20 and 21 for file transfer, 23 for remote 
login
6. Presentation: POP, SMTP, HTTP
7. Application: Email, Web Browsers, File transfer, Newsgroups, Remote login

Answers to 22-28:

22. Interface to User, displaying information and interpreting input

23 Getting digital messages into physical formats

24. Finding optimal routing for messages to reach their destination

25. Transmitting signals between network nodes

26. Client-server communication protocols

27. Keeping track of which application is talking to which network node

28. Packaging information for transmission

Questions and answers Copyright (C) 2002, by Laurence J. Krieg and 
Washtenaw Community College. All rights reserved.