Essential Networking Interview Questions Part – 4
1.Define Network?
A network is a set of devices connected by physical media links. A network is recursively is a connection of two or more nodes by a physical link or two or more networks connected by one or more nodes.
2.What is Protocol?
A protocol is a set of rules that govern all aspects of information communication.
3.What is a Link?
At the lowest level,a network can consist of two or more computers directly connected by some physical medium such as coaxial cable or optical fiber. Such a physical medium is called as Link.
4.What is a node?
A network can consist of two or more computers directly connected by some physical medium such as coaxial cable or optical fiber. Such a physical medium is called as Links and the computer it connects is called as Nodes.
5.What is a gateway or Router?
A node that is connected to two or more networks is commonly called as router or Gateway. It generally forwards message from one network to another.
6.Name the factors that affect the performance of the network?
a.Number of Users
b. Type of transmission medium
c. Hardware
d. Software
7.What is Round Trip Time?
The duration of time it takes to send a message from one end of a network to the other and back,is called RTT.
8.List the layers of OSI
a. Physical Layer
b. Data Link Layer
c. Network Layer
d. Transport Layer
e. Session Layer
f. Presentation Layer
g. Application Layer
9.Which layers are network support layers?
a. Physical Layer
b. Data link Layer and
c. Network Layers
10.Which layers are user support layers?
a. Session Layer
b. Presentation Layer and
c. Application Layer
11.What is Pipelining ?
In networking and in other areas,a task is often begun before the previous task has ended. This is known as pipelining.
12.What is Piggy Backing?
A technique called piggybacking is used to improve the efficiency of the bidirectional protocols. When a frame is carrying data from A to B,it can also carry control information about arrived (or lost) frames from B; when a frame is carrying data from B to A,it can also carry control information about the arrived (or lost) frames from A.
13.What are the two types of transmission technology available?
(i) Broadcast and
(ii) point-to-point
14.What is Bandwidth?
Every line has an upper limit and a lower limit on the frequency of signals it can carry. This limited range is called the bandwidth.
15.Explain RIP (Routing Information Protocol)
It is a simple protocol used to exchange information between the routers.
16.What is subnet?
A generic term for section of a large networks usually separated by a bridge or router.
17.What is MAC address?
The address for a device as it is identified at the Media Access Control (MAC) layer in the network architecture. MAC address is usually stored in ROM on the network adapter card and is unique.
18.What is multiplexing?
Multiplexing is the process of dividing a link,the phycal medium,into logical channels for better efficiency. Here medium is not changed but it has several channels instead of one.
19.What is simplex?
It is the mode of communication between two devices in which flow of data is unidirectional.
i.e. one can transmit and other can receive.
E.g. keyboard and monitor.
20.What is half-duplex?
It is the mode of communication between two devices in which flow of data is bi-directional but not at the same time. ie each station can transmit and receive but not at the same time.
E.g walkie-talkies are half-duplex system.
21.What is full duplex?
It is the mode of communication between two devices in which flow of data is bi-directional and it occurs simultaneously. Here signals going in either direction share the capacity of the link.
E.g. telephone
22.What is sampling?
It is the process of obtaining amplitude of a signal at regular intervals.
23.What is Asynchronous mode of data transmission?
It is a serial mode of transmission. In this mode of transmission,each byte is framed with a start bit and a stop bit. There may be a variable length gap between each byte.
24.What is Synchronous mode of data transmission?
It is a serial mode of transmission.In this mode of transmission,bits are sent in a continuous stream without start and stop bit and without gaps between bytes. Regrouping the bits into meaningful bytes is the responsibility of the receiver.
25.What are the different types of multiplexing?
Multiplexing is of three types. Frequency division multiplexing and wave division multiplexing is for analog signals and time division multiplexing is for digital signals.
26.What are the different transmission media?
The transmission media is broadly categorized into two types
i)Guided media(wired)
i)Unguided media(wireless)
27.What are the duties of data link layer?
Data link layer is responsible for carrying packets from one hop (computer or router) to the next. The duties of data link layer include packeting,addressing,error control,flow control,medium access control.
28.What are the types of errors?
Errors can be categorized as a single-bit error or burst error. A single bit error has one bit error per data unit. A burst error has two or more bits errors per data unit.
29.What do you mean by redundancy?
Redundancy is the concept of sending extra bits for use in error detection. Three common redundancy methods are parity check,cyclic redundancy check (CRC),and checksum.
30.Define parity check.
In parity check,a parity bit is added to every data unit so that the total number of 1s is even (or odd for odd parity).Simple parity check can detect all single bit errors. It can detect burst errors only if the total number of errors in each data unit is odd.In two dimensional parity checks,a block of bits is divided into rows and a redundant row of bits is added to the whole block.