Chapter-17
1)What is HUB?
⇒A
Hub is a device that operates only in the
physical Layer.
2)What is repeater and how it works in a Hub?
⇒A
repeater is a device which receives a signal
and, before it becomes too weak or corrupted
regenerates and retimes the original bit pattern.
3)Why a repeater was used when a Ethernet LANs
were using bus Topology?
⇒A
repeater was used to connect two segments of
a LAN to overcome the length restriction of the
coaxial cable.
4)Which network Topology often called a Hub?
⇒Star
Topology.
5)In a Star Topology what is the uses of a repeater
in a Hub?
⇒It
can be used to serve as the connecting point
and at the same time Function.
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6)Which device has no Filtering Capability?
⇒A
repeater or a Hub.
7)Why a Hub or a repeater do not have a link-layer
address?
⇒They
do not have a link-layer address because
they just regenerate the corrupted bits and send
them out from every port.
8)Which device operates in both the Physical and
the data-link Layer?
⇒A
Switch.
9)Which Capability has access in a link-layer
Switch?
⇒Filtering.
10)How does a Filtering Capability has work in a
Switch?
⇒It
can check the destination address of a frame
and can decide from which outgoing port the
frame should be sent.
11)In Switch, what has used in filtering decisions?
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⇒A
Table.
12) In Switch Which address does not change the
link layer in a frame?
⇒MAC
Address.
13) What is Transparent Switches?
⇒A
Transparent Switch is a Switch in which the
Stations are completely unaware of the switch's
existence.
14 )What is unnecessary when a switch is added or
deleted from the system?
⇒Reconfiguration
of the station.
15 )In a Transparent switches what is the position
of a Frame from one station to another?
⇒It
must be forwarding.
16 )In a Transparent system what should be
prevented?
⇒Loops.
17 )What is the meaning of redundant Switches?
⇒More
than one switch between a pair of LAN's.
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18 )Which device can create Loops in the system?
⇒Redundancy.
19 )How does a Loop can be created by more than
one Switch?
⇒When
two or more broadcasting LAN's are
connected.
20 )From which specification require to solve the
looping problem?
⇒IEEE.
21 )In a IEEE specification how does switches use
to create a Loop less Topology?
⇒To
create a spanning tree algorithm.
22 )What is spanning Tree?
⇒Spanning
Tree is a graph in which there is no
Loop.
23 )Why we cannot changes the physical
Topology a system?
⇒Because
physical connections are between cables
and switches.
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24 )Which Topology can create the overlays in the
physical one?
⇒Logical.
25 )In, Some of textbooks which name can be
replaced as LAN's?
⇒Nodes.
26 )In some textbooks which device can be
represent as connecting arcs?
⇒Switches.
27 )What is the meaning of shortest path?
⇒A
path with the shortest cost.
28 )What does the connecting arcs show in a
switch?
⇒The connection of a LAN to a switch and vice
versa.
29 ) Which Switch has selected the smallest ID of
a switch?
⇒roofs
switch.
30 ) What does the meaning of roofs?
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⇒Root
of the tree.
31 ) How does a shortest Tree can be created?
⇒ The
combination of the shortest paths.
32 ) What is forwarding ports?
⇒The
Forwarding port, which forward a frame
that the switch receives.
33 )What is blocking ports?
⇒ The
blocking ports, which block the frames
received by the switch.
34 )How much path in the spanning tree system
from one LAN to another LAN?
⇒Only
one path.
35 ) How does each switch is equipped?
⇒ With
a software package.
36 )Which switch has several advantages over a
hub?
⇒ Link
-Layer.
37 ) Which LAN doesn't need for carrier sensing
and collision detection?
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⇒ Switched
LAN.
38 ) In a Switch, which device can receive a
Frame?
⇒Twisted
-pair cable.
39 )How much data can sends at Twisted -pair
cable?
⇒ 10Mbps.
40 )In switch, Which device can deliver the frame
to another device?
⇒ Fiber-
optic cable.
41 ) How much data can receive at fiber-optic
cable?
⇒
1OO Mbps.
42 ) What is router?
⇒A
router is a three - layer device; it operates is
the physical, data-link and network layers.
43 ) How does a physical layer works in a router?
⇒ It regenerates the signal it receives.
44 ) How does a data-link Layer works in a router?
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⇒ The
router checks the physical address contained
in the packet.
45 ) How does a network- layer works in a router?
⇒A
router checks the network-layer address.
46 ) Which device can connect Network?
⇒A
router.
47 ) Which device has a physical and logical
address?
⇒A
router.
48 ) In a router, Which address is changes in a
Packet?
⇒ Link-
Layer.
49 ) What is the full form of (VLAN ) ?
⇒ Virtual
local area network.
50) What is VLAN?
⇒a
virtual local area network is a local area
network configured by software ,not by physical
wiring.
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