1 Modulation is the
process of sending a file from one computer to another computer.
False
2 Error correction and
detection in OSI model is done by
Data link Layer , Transport Layer
3 The
functions of ATM layers are
Routing , Switching ,Multiplexing
4 The
virtual circuit approach of packet switching is used in
Data Link layer
5 ATM
standard defines ________ layer.
Three
6 Repeater
operates in
Physical layer
7 A
hub is actually
A multiport repeater
8 A
central computer surrounded by one or more satellite computers is called a bus network.
False
9 Which
of the following connects LAN to a WAN?
A network
gateway
10 Devices
on one network can communicate with device on another network via a gateway.
True
11Error
control is based on
ARQ
12 Transition
states of PPP are
Idle
state , Establishment state , Authenticating state
13 Transport
layer is responsible for delivery of ________ from one node to other.
Message
14 Packets
in the IP layer are called
Datagrams
15 The
primary function of a bridge is to
Interconnect
two LANs
Full – duplex = Simultaneous transmission in both directions
Modem =
Modulator Demodulator
Bit =
Binary digit Binary digit
Synchronous
communication
efficiency = High Band width of the medium
16 The
application layer of a network consists of software being run on
the computer connected to the network.
True
Multiplexing = FDM
Bounded Media = Fiber optic cable
Wireless Transmission = Microwave
Highest Attention = UTP cable
17Which
of the following connects LAN to another of the same type?
A network
bridge
18A
remote bridge
Useful for several offices with LANs , Acts as point-to- point link , Uses PPP protocol
19 The
communication mode that supports two-way traffic but only one direction at a time is known as half duplex.
True
20 The
size of the datagram is
8 bytes
21 The
layer lies between the network layer and the session layer is
Transport layer
22 The
digital, voice, or video voltages are referred to as ____ signals.
Base band
23 OSPF
features are
Multiple circuit load balancing , Converge very quickly to network topology change , Not
susceptible to routing loops
24 Contention
is
The condition when two or more stations attempt to use the same channel at the same time
25 A
communication protocol always have ________.
Set of
symbols
26 A
transport layer
Receives Service from Network layer , Gives
service to Application layer
27 X
. 25 protocol
Allows DTE to DCE
interface , Is a synchronous interface , Is approved by CCITT
28 The
5-7 digits are known as the country code of the Network User Address (NUA)
False
29 As
the data packet moves from the lower to the upper layers, headers are
Added
30 X.25
uses
Packet assembler/disassembler , Packet switched network , Access lines to public data networks
31 For
connecting several LANs, backbone networks are used.
True
32 Data
rates above the 20,000 bps limitation of the RS-232 standard become possible by
Shortening the cable
33 The
medium that permits the highest data rate is ________.
Fiber optic cable
34 The
________ Timer is used in termination phase.
Time
waited
35 Internet
protocol is a
Host-to-host delivery network layer protocol
36 Network
layer is responsible for delivery of ________ from one source to other.
Packets
37 Gateway
is used for modulation and demodulation. False
38 ARQ
stands for
Automatic repeat request
39 Query
message that ICMP supports
Echo request and reply , Timestamp request and reply , Router solicitation and advertisement
40 Which
organisation has developed much of the original standards?
IEEE
41 The
________ timer keep a track of the time between the sending of segment and the receipt of an acknowledgement.
Retransmission
42 The
important features of a repeater are
Can use 10Base5 , Acts
as two port node , Operates only in physical
layer
43 A
medium access control technique for multiple access transmission media is amplitude.
False
44 The
X.25 standard covers ________ OSI layers.
3
45The
available BW is divided into bands is
FDMA
46 Digital
transmission is possible in
Serial mode , Parallel mode
47 Network
File System (NFS) allow computers to share files across a network or networks.
True
48 Serial
transmission can be
Synchronous , Asynchronous
49 Transmission
media is characterized by
Throughput , Propagation speed , Propagation
time
Time waited timer = Termination phase
Keep Alive Timer = Prevents long idle
connection
Persistence timer = Handles zero window size
Retransmission timer = Lost segments
50 The
datagram approach of packet switching is used in
Network layer
