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 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.
3. 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.
4. 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.
5. What is point-point link?
If the physical links are limited to a pair of nodes it is said to be point-point link.
6. What is Multiple Access/multipoint ?
If the physical links are shared by more than two nodes, it is said to be Multiple Access.
7. What are the advantages of Distributed Processing?
a. Security/Encapsulation
b. Distributed database
c. Faster Problem solving
d. Security through redundancy
e. Collaborative Processing
8. What are the criteria necessary for an effective and efficient network?
a. Performance
   It can be measured in many ways, including transmit time and response time. b. Reliability
   It is measured by frequency of failure, the time it takes a link to recover from a failure, and the network's robustness.
c. Security
   Security issues includes protecting data from unauthorized access and virues.
9. Name the factors that affect the performance of the network?
a. Number of Users
b. Type of transmission medium
c. Hardware
d. Software
10. Name the factors that affect the reliability of the network?
a. Frequency of failure
b. Recovery time of a network after a failure
11. Name the factors that affect the security of the network?
a. Unauthorized Access
b. Viruses
12. What is Protocol?
A protocol is a set of rules that govern all aspects of information communication.
13. What are the key elements of protocols?
The key elements of protocols are
a. Syntax
   It refers to the structure or format of the data, that is the order in which they are presented.
b. Semantics
   It refers to the meaning of each section of bits.
c. Timing
   Timing refers to two characteristics: When data should be sent and how fast they can be sent.
14. What are the key design issues of a computer Network?
a. Connectivity
b. Cost-effective Resource Sharing
c. Support for common Services
d. Performance
15. Define Bandwidth and Latency?
Network performance is measured in Bandwidth (throughput) and Latency (Delay). Bandwidth of a network is given by the number of bits that can be transmitted over the network in a certain period of time. Latency corresponds to how long it takes a message to travel from one end off a network to the other. It is strictly measured in terms of time.
16. Define Routing?
The process of determining systematically how to forward messages toward the destination nodes based on its address is called routing.
17. What is a peer-peer process?
The processes on each machine that communicate at a given layer are called peer-peer process.
18. When a switch is said to be congested?
It is possible that a switch receives packets faster than the shared link can accommodate and stores in its memory, for an extended period of time, then the switch will eventually run out of buffer space, and some packets will have to be dropped and in this state is said to congested state.
25. What is WDM?
WDM is conceptually the same as FDM, except that the multiplexing and demultiplexing involve light signals transmitted through fiber optics channel.
26. What is TDM?
TDM is a digital process that can be applied when the data rate capacity of the transmission medium is greater than the data rate required by the sending and receiving devices.
27. What is Synchronous TDM?
In STDM, the multiplexer allocates exactly the same time slot to each device at all times, whether or not a device has anything to transmit.
28. 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
29. Which layers are network support layers?
a. Physical Layer
b. Data link Layer and 
c. Network Layers
30. Which layers are user support layers?
a. Session Layer
b. Presentation Layer and 
c. Application Layer
31. Which layer links the network support layers and user support layers?
The Transport layer links the network support layers and user support layers.
32. What are the concerns of the Physical Layer?
Physical layer coordinates the functions required to transmit a bit stream over a physical medium.
a. Physical characteristics of interfaces and media
b. Representation of bits
c. Data rate
d. Synchronization of bits
e. Line configuration
f. Physical topology
g. Transmission mode
33. What are the responsibilities of Data Link Layer?
The Data Link Layer transforms the physical layer, a raw transmission facility, to a reliable link and is responsible for node-node delivery.
a. Framing
b. Physical Addressing
c. Flow Control
d. Error Control
e. Access Control
34. What are the responsibilities of Network Layer?
The Network Layer is responsible for the source-to-destination delivery of packet possibly across multiple networks (links).
a. Logical Addressing
b. Routing
35. What are the responsibilities of Transport Layer?
The Transport Layer is responsible for source-to-destination delivery of the entire message.
a. Service-point Addressing
b. Segmentation and reassembly
c. Connection Control
d. Flow Control
e. Error Control
36. What are the responsibilities of Session Layer?
The Session layer is the network dialog Controller. It establishes, maintains and synchronizes the interaction between the communicating systems.
a. Dialog control
b. Synchronization
37. What are the responsibilities of Presentation Layer?
The Presentation layer is concerned with the syntax and semantics of the information exchanged between two systems.
a. Translation
b. Encryption
c. Compression
38. What are the responsibilities of Application Layer?
The Application Layer enables the user, whether human or software, to access the network. It provides user interfaces and support for services such as e-mail, shared database management and other types of distributed information services.
a. Network virtual Terminal
b. File transfer, access and Management (FTAM)
c. Mail services
d. Directory Services
39. What are the two classes of hardware building blocks?
Nodes and Links.
40. What are the different link types used to build a computer network?
a. Cables
b. Leased Lines
c. Last-Mile Links
d. Wireless Links
41. What are the categories of Transmission media?
a. Guided Media
  i. Twisted - Pair cable
    1. Shielded TP
    2. Unshielded TP
  ii. Coaxial Cable
  iii. Fiber-optic cable
b. Unguided Media
  i. Terrestrial microwave
  ii. Satellite Communication
42. What are the types of errors?
a. Single-Bit error
  In a single-bit error, only one bit in the data unit has changed
b. Burst Error
  A Burst error means that two or more bits in the data have changed.


1 comment:

Tamal kumar Das said...

For Best Classroom Coaching Crash Course In Kolkata Or Study Materials (Online/Offline) Solved Previous Year Papers Tips Tricks Strategies & Preparation Plan ForIBPS CWE PO & SPECIALIST OFFICER IT/LAW/HR/MARKETING Entrance Exam 2015 Visit http://tsa1998.blogspot.in