10 questions to initialize the journey

1. Explain Data and Types?
Data can be defined as a systematic record of a particular quantity. 
In other word data may be defined as character or group of character.
-Depending upon types of character data has been divided into following types.
1)Alphabetic data
2)Numeric data
3)Alphanumeric data

2. What is information and information security?

-Very structured data for the particular person or organization is called information.

-Simply processed data is called information.

-information system is associated with input,Process and output.

Information security:We must know that information is valuable for any organization and it must be secure to maintain the value of information.

                                   security means information should be only accessed by by authorized user and information should not be lost or theft 

                                   because of any unavoidable circumstances.

(Authorization-Access permission, Authentication-We can read not write. eg. Checking user validation)

3.Explain CIA concept for information security

This is the value concept associated with information security and which explains as:

Confidential-Any authorized user can access the system information and information should not come in contact with the wrong hands.

Integrity-Data/Information should not be modifiable else whole meaning of information will be meaningless

 

4.What is software and hardware?

Computer hardware is any physical device used in or with your machine, whereas software is a collection of programming code installed on your computer's hard drive. In other words, hardware is something you can hold in your hand, whereas software cannot be held in your hand. You can touch hardware, but you cannot touch software. Hardware is physical, and software is virtual.

5.Types of software?

Application software-requires to fulfill our requirements eg. MS office,tally banking software etc.

System software- Operating system responsible to perform everything happening within the system like Process management, Memory management, File management. eg. Windows,Linux,mac,android.

Program:A set of instructions in particular order to perform specific task is a program.

6.Types of operating system?

GUI stands for graphical user interface.

It is a user interface which user interact with applications by making use of graphics.

In GUI more than one task can run simultaneously.

The user interacts by pointing the applications using devices like mouse.

It is a very user friendly interface.

Example(Windows, Linux)

CUI stands for character user interface.

In CUI user has to interact with the applications by making use of commands.

In CUI only one task can run at a time.

Additional information :-

CUI and GUI are user interface used in connection with computers

• CUI is the precursor of GUI and stands for character user interface where user has to type on keyboard to proceed. On the other hand GUI stands for Graphical User Interface which makes it possible to use a mouse instead of keyboard

• GUI is much easier to navigate than CUI

• There is only text in case of CUI whereas there are graphics and other visual clues in case of GUI

• Most modern computers use GUI and not CUI

• DOS is an example of CUI whereas Windows is an example of GUI.

7. What is Networking? Explain importance.

When a no of systems are interconnected with each other though communication media in order to fulfill the requirements called network. 

Importance: Main objective is to support the feature resource utilization and information sharing.

Eg. Resource utilization in bank-one server multiple users 

8.Types of network?

There are five types of topology in computer networks:

1. Mesh Topology
2. Star Topology
3. Bus Topology
4. Ring Topology
5. Hybrid Topology

Mesh Topology

In mesh topology each device is connected to every other device on the network through a dedicated point-to-point link. When we say dedicated it means that the link only carries data for the two connected devices only. Lets say we have n devices in the network then each device must be connected with (n-1) devices of the network. Number of links in a mesh topology of n devices would be n(n-1)/2.

Advantages of Mesh topology

1. No data traffic issues as there is a dedicated link between two devices which means the link is only available for those two devices.
2. Mesh topology is reliable and robust as failure of one link doesn’t affect other links and the communication between other devices on the network.
3. Mesh topology is secure because there is a point to point link thus unauthorized access is not possible.
4. Fault detection is easy.

Disadvantages of Mesh topology

1. Amount of wires required to connected each system is tedious and headache.
2. Since each device needs to be connected with other devices, number of I/O ports required must be huge.
3. Scalability issues because a device cannot be connected with large number of devices with a dedicated point to point link.

Star Topology

In star topology each device in the network is connected to a central device called hub. Unlike Mesh topology, star topology doesn’t allow direct communication between devices, a device must have to communicate through hub. If one device wants to send data to other device, it has to first send the data to hub and then the hub transmit that data to the designated device.

Advantages of Star topology

1. Less expensive because each device only need one I/O port and needs to be connected with hub with one link.
2. Easier to install
3. Less amount of cables required because each device needs to be connected with the hub only.
4. Robust, if one link fails, other links will work just fine.
5. Easy fault detection because the link can be easily identified.

Disadvantages of Star topology

1. If hub goes down everything goes down, none of the devices can work without hub.
2. Hub requires more resources and regular maintenance because it is the central system of star topology.

Bus Topology

In bus topology there is a main cable and all the devices are connected to this main cable through drop lines. There is a device called tap that connects the drop line to the main cable. Since all the data is transmitted over the main cable, there is a limit of drop lines and the distance a main cable can have.

Advantages of bus topology

1. Easy installation, each cable needs to be connected with backbone cable.
2. Less cables required than Mesh and star topology

Disadvantages of bus topology

1. Difficultly in fault detection.
2. Not scalable as there is a limit of how many nodes you can connect with backbone cable.

Ring Topology

In ring topology each device is connected with the two devices on either side of it. There are two dedicated point to point links a device has with the devices on the either side of it. This structure forms a ring thus it is known as ring topology. If a device wants to send data to another device then it sends the data in one direction, each device in ring topology has a repeater, if the received data is intended for other device then repeater forwards this data until the intended device receives it.

Advantages of Ring Topology

1. Easy to install.
2. Managing is easier as to add or remove a device from the topology only two links are required to be changed.

Disadvantages of Ring Topology

1. A link failure can fail the entire network as the signal will not travel forward due to failure.
2. Data traffic issues, since all the data is circulating in a ring.

Hybrid topology

A combination of two or more topology is known as hybrid topology. For example a combination of star and mesh topology is known as hybrid topology.

Advantages of Hybrid topology

1. We can choose the topology based on the requirement for example, scalability is our concern then we can use star topology instead of bus technology.
2. Scalable as we can further connect other computer networks with the existing networks with different topologies.

Disadvantages of Hybrid topology

1. Fault detection is difficult.
2. Installation is difficult.
3. Design is complex so maintenance is high thus expensive.

9.Explain ISO-OSI model in networking?

The ISO-OSI model is a seven layer architecture. It defines seven layers or levels in a complete communication system. They are:

1. Application Layer
2. Presentation Layer
3. Session Layer
4. Transport Layer
5. Network Layer
6. Datalink Layer
7. Physical Layer

Below we have the complete representation of the OSI model, showcasing all the layers and how they communicate with each other.

In the table below, we have specified the protocols used and the data unit exchanged by each layer of the OSI Model.

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Feature of OSI Model

1. Big picture of communication over network is understandable through this OSI model.
2. We see how hardware and software work together.
3. We can understand new technologies as they are developed.
4. Troubleshooting is easier by separate networks.
5. Can be used to compare basic functional relationships on different networks.

10. TCP /UDP ports:

About TCP/UDP Ports

• Port Number 0 to 1023: These TCP/UDP port numbers are known well-known ports. These ports are assigned to specific server sevice by the Internet Assigned Numbers Authority (IANA). For example, port 80 is used by web servers.
• Port Numbers 1024 to 49151: These are ports that an organization, such as application developers, can register with IAMA to be used for a particular service. These should be treated as semi-reserved.
• Port Numbers 49152 to 65535: These are port numbers used by client programs, such as a web browser. When you visit a web site, your web browser will assign that session a port number from within this range. As an application developer, you are free to use any of these ports.