basic data and voice communication

STRATHMORE UNIVE
ERSITY
FACULT OF INFO
TY
ORMATION TECHNOLOGY
ACHELOR O SCIENC IN TELEC
OF
CE
COMMUNIC
CATIONS
BA
BTC 120 Basic Dat and Voice Communica
02:
ta ations DATE: 13th March 20
3
012
Instructio
ons:
Answer q question 1 and any other t questions d two s All Quest tions carry 20 marks each

HRS
TIME: 2 H

QUESTIO 1 (COMPULSORY)
ON
a. Match the followin functions t a layer of th OSI model h ng to he
i.
ii. iii. iv.
v.

(5 Marks)

Reliable pr rocess-to-process message delivery e Route sele ection Defines fra ames Provides user services s u such as e-mai and file tran il nsfer
Transmission of bit stre across ph eam hysical mediu um wer wing multiple c choice questions:
b. Answ the follow
i.

The _____ is the phy
___
ysical path over which a me essage travels
s.
A. Protocol B. Medium
P

ii. iii. iv.

h rk) (Each carries 1 mar

C. Signal

D. All

Which of the OSI layers is represent by frames? t ted
A. Session B. Datalink t ork
C. Transport D. Netwo
The proces ss-to-process delivery of th entire message is the responsibility o the ______ he of
__
layer.
N
on cal A. Network B. Transport C. Applicatio D. Physic
Before dat can be trans ta smitted, they must be trans sformed to __
_______.
A. Periodic signals
P

tromagnetic s signals B. Elect

C.
C Aperiodic s signals D . Low frequen sine wave ncy es
v.

ncy
,
________.
As frequen increases, the period _
A. Decreases B. Increases
D

vi.

D.
D Doubles

Unipolar, bipolar, and p b polar encodin are types of _______ encoding. ng f
A. Line
L

vii.

C. Remains t same the B. Block

C. N
NRZ

D.
D Manchester r PCM is an example of _______ conversion. i e
A. Digital-to-Digital B. Digit
D
tal-to-Analog g C. Analog g-to-Analog D. Analog-to-

Digital
D
viii.

AM and FM are examp of ______ conversio
M
ples
___
on.
1

A.