Define computer
network.
Computer network is a
connection of autonomous computers and network devices for:
Resource
sharing (data/devices) in an efficient manner Communication amongst them.
Compare simplex and
duplex communication with example.
In
simplex mode, the communication is unidirectional (Eg: keyboard,
monitor).
In
half-duplex mode, each station can both transmit and receive, but
not simultaneously (Eg. walkie-talkie).
In
full-duplex (also called duplex), both stations can transmit and
receive simultaneously (Eg. telephone network).
List the criteria
based on which a network can be assessed.
Performance is
based on its throughput (no. of packets delivered) and delay. Reliability is
how much the network is fault tolerant.
Security includes preventing
unauthorized access and recovery from breaches.
What are the two
types of line configuration?
A
point-to-point connection provides a dedicated link between two nodes.
In a multipoint connection, more than two nodes
share a single link, i.e., bandwidth is shared amongst the nodes..
Classify LAN, WAN,
MAN and Internetwork.
LAN is privately owned and links
the devices in a single office, building, or campus. The LAN size is
limited to a few kilometers. A LAN will use only one type of transmission
medium. The speed of LAN is in the range 10–1000 Mbps.
WAN provides long-distance
transmission of data, image, audio, and video information over large
geographic areas that may comprise a country, a continent, or the whole world.
MAN is a network with a size
between a LAN and a WAN. It normally covers the area inside a town or a
city. It is designed for customers who need a high-speed connectivity to the
Internet, and have endpoints spread over a city or part of city.
When
two or more independent networks are connected, it becomes an internetwork or internet.
List the advantages
of layering.
It
decomposes the problem of building a network into more manageable components.
It provides a more modular design. To add a new service,
then it is only needed to modify the functionality at one layer, reusing the
functions at all the other layers.
Uses abstraction to hide complexity of network from
application.
Define protocol.
The abstract objects that make up the layers of a network
system are called protocols. Each protocol defines two different interfaces.
o Service interface that
specifies the set of operations
o
Peer-to-peer interface
for messages to be exchanged amongst peers Protocol is a set of rules
that govern communications between devices.
