This set of Data communication and Networking Multiple Choice Questions and Answers (MCQs) focuses on “Integrated Services Digital Network (ISDN) ”.
1. The part of the address field in an LAPD frame that defines the upper-layer service is called ________.
- TEI
- SAPI
- CR
- none of the above
2. The part of the address field in an LAPD frame that uniquely defines a TE is called ________.
- TEI
- SAPI
- CR
- none of the above
3. Which of the following (in decimal) is not a valid SAPI?
- 56
- 42
- 64
- 63
4. When an LAPD frame uses the D channel for signaling, the value of SAPI (in decimal) is ______________.
- 0
- 63
- 64
- 1
5. When an LAPD frame uses the D channel for data transmission, the value of SAPI (in decimal) is ______________.
- 0
- 63
- 64
- 16
6. When an LAPD frame uses management data, the value of SAPI (in decimal) is _________
- 0
- 63
- 16
- 1
7. Which of the following (in decimal) is not a valid TEI?
- 56
- 128
- 64
- 63
8. The TEI can define up to _________ TEs.
- 8
- 128
- 64
- 32
9. The value of an LAPD address is 00000000 11111111. This is a _________ frame.
- command
- response
- a or b
- neither a nor b
10. The value of an LAPD address is 00000000 00010001. The frame is destined for a TE with address _________.
- 4
- 6
- 8
- none of the above
11. The network layer of the D channel is defined by the _______ protocol
- Q.931
- I.430
- I.431
- neither a nor b
12. When a user dials a number, which of the following messages is sent by the D channel to the network?
- setup
- connect
- progress
- none of the above
13. To initiate a call, which of the following messages is sent by the D channel?
- setup
- connect
- progress
- none of the above
14. Acceptance of a call requires a _______ message in an LAPD frame.
- setup
- connect
- progress
- none of the above
15. Which message is sent by the D channel to show that call establishment is in progress?
- setup
- connect
- progress
- none of the above
16. To re-establish a suspended call, a user sends a ___________ message.
- setup
- resume
- progress
- none of the above
17. An ISDN address is ___________ digits long.
- 10
- 40
- 55
- none of the above
18. An ISDN address uses _______ decimal digits to define a country code.
- 3
- 2
- 10
- none of the above
19. An ISDN address can define up to _________ countries.
- 10
- 100
- 1000
- none of the above
20. An ISDN address uses _______ decimal digits to define a network inside a country.
- 3
- 2
- 9
- none of the above
21. An ISDN address can define up to _________ networks inside a country
- 10
- 100
- 1000
- none of the above
22. An ISDN address uses _______ decimal digits to define a subscriber.
- 3
- 9
- 10
- none of the above
23. An ISDN address can define up to _________ subscribers.
- 106
- 109
- 1010
- none of the above
24. An ISDN address uses _______ decimal digits to define a subaddress.
- 30
- 40
- 20
- none of the above
25. An ISDN address can define up to _________ subaddresses.
- 106
- 109
- 1010
- none of the above