osi layers self testing questions

Prepared by Nukala Prabhakar, Divisional Engineer, IT Project Circle, Pune 1

Self Testing Questions on OSI layers Choose the correct answer among the FOUR alternative choices given against each question:

1. The OSI model consists of ___ layers [ ]

(a) Three (b) Five (c) Seven (d) Eight

2. The _____ layer decides the location of synchronization points [ ]

(a) Transport (b) Session (c) Presentation (d) Application

3. The end-to-end delivery of the entire message is the responsibility of [ ] the _____ layer

(a) Network (b) Transport (c) Session (d) Presentation

4. The ___ layer is the layer closest to the transmission medium [ ]

(a) Physical (b) Data link (c) Network (d) Transport

5. In the ____ layer, the data unit is called a frame [ ]

(a) Physical (b) Data link (c) Network (d) Transport

6. Decryption and encryption of data are the responsibility of [ ] the ______ layer

(a) Presentation (b) Data link (c) Network (d) Transport


7. Dialog control is a function of the _____ layer [ ]


8. Mail services and directory services are available to network users [ ] through the ____ layers

(a) Data link (b) Sesssion (c) Transport (d) Application

9. Node-to-node delivery of the data unit is the responsibility of [ ] the _____ layer

(a) Physical (b) Data link (c) Transport (d) Network

10. As the data packet moves from the lower to the upper layers, headers [ ] are _______

(a) added (b) subtracted (c) rearranged (d) modified

11. As the data packet moves from the upper to the lower layers, headers [ ] are _______

(a) added (b) subtracted (c) rearranged (d) modified

12. The _______ layer lies between the network layer and the session [ ] layer

(a) Physical (b) Data link (c) Transport (d) Presentation


13. When data are transmitted from device A to device B, the header from [ ] As layer 5 is read by Bs ______ layer

(a) Physical (b) Transport (c) Session (d) Presentation

14. In the ______ layer, translations from one character code to another [ ] occur.


15. The _____ layer changes bits into electromagnetic signals. [ ]


16. The ____ layer can use the trailer of the frame for error detection [ ]


17. The physical layer is concerned with the transmission of ____ over [ ] the physical medium

(a) Programs (b) Dialogs (c) Protocols (d) Bits

18. What is the main function of the transport layer? [ ]

(a) node-to-node delivery (b) end-to-end message delivery (c) synchronization (d) updating and maintenance of routing tables


19. Session layer checkpoints ________ [ ]

(a) allow just a portion of a file to be resent (b) detect and recover errors (c) control the addition of headers (d) are involved in dialog control 20. Which of the following is an application layer service? [ ]

(a) Network virtual terminal (b) File transfer, access, and management (c) Mail service (d) All of the above 21. LAN protocols operate in the ____ of OSI Reference model [ ] (a) Data Link Layer (b) Physical and Data Link Layers (c) Network Layer (d) Lower three layers 22. WAN protocols operate in the ____ of OSI Reference model [ ] (a) Data Link Layer (b) Physical Layer (c) Network Layer (d) Lower three layers 23. Routing protocols operate in the ____ of OSI Reference model [ ] (a) Data Link Layer (b) Physical Layer (c) Network Layer (d) Lower three layers 24. Following are the examples of Session layer [ ] (a) ASCII, EBCDIC (b) NFS, SQL, RPC (c) FTP, SMTP (d) None of these 25. Following are the examples of Network layer protocols [ ] (a) NFS, SQL, RPC (b) FDDI, Token ring (c) IP, IPX, AppleTalk (d) None of these

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Key:

(1) c; (2) b; (3) b; (4) a; (5) b; (6) a; (7) b; (8) d; (9) b; (10) b; (11) a; (12) c; (13) c;

(14) c; (15) a; (16) b; (17) d; (18) b; (19) a; (20) d; (21) b; (22) d; (23) c; (24) b; (25) c;

osi layers self testing questions

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