Table of Contents

PART – A

Q1. Write any two internal commands of DOS.

Ans. DIR, COPY.

Q2. What is PageMaker?

Ans. PageMaker is a sophisticated page layout software used to design and produce documents for printing. It is versatile enough to create anything from a simple business card to a complex, multi-page book. It allows users to:

  • Position text and graphics with precision.
  • Create professional newsletters, brochures, and reports.
  • Integrate elements from other software (like MS Word or Excel) into a single layout.

Q3. What is Workbook?

Ans. The entire Excel file that contains one or more worksheets (like a notebook) is known as the workbook. By default, there are three worksheets in a workbook.

Q4. What is Cell?

Ans. A cell is the intersection of a row and a column where data is entered (e.g., A1).

Q5. What is Logical Function?

Ans. In Microsoft Excel, a Logical Function is a formula used to evaluate whether a specific condition or criteria is True or False. For E.g.: IF, AND, OR, NOT.

If you want to check if a student passed (score over 50), you would use: =IF(A1>50, "Pass", "Fail")

Q6. What is DBMS?

Ans. A Database Management System (DBMS) is software that acts as an interface between a user and a database. It allows users to store, retrieve, update, and manage data efficiently while ensuring security and consistency. Think of it as a digital filing cabinet where the software manages how files are tucked away and found.

Q7. What is freezing a field in DBMS?

Ans. In DBMS, freezing a field (often referred to as "Freezing Columns") is a feature used to keep specific columns visible on the screen while scrolling horizontally through a large dataset.

Q8. W1rn t is Multimedia?

Ans. The term Multimedia is a linguistic blend of two words: "Multi," meaning many, and "Media," referring to the material or medium through which information is transmitted or sent. It is defined as the integration of various media elements, such as text, graphics, audio, and video, to present information in a more effective, engaging, and attractive manner.

Q9. What is Mesh Topology?

Ans. In Mesh Topology, a host is connected to one or multiple hosts. This topology has hosts in point-to-point connection with every other host or may also have hosts which are in point-to point connection to few hosts only.

Hosts in Mesh topology also work as relay for other hosts which do not have direct point-to point links.

Mesh technology comes into two types:

  1. Full Mesh: All hosts have a point-to-point connection to every other host in the network. Thus for every new host n(n-1)/2 connections are required. It provides the most reliable network structure among all network topologies.
  2. Partially Mesh: Not all hosts have point-to-point connection to every other host. Hosts connect to each other in some arbitrarily fashion. This topology exists where we need to provide reliability to some hosts out of all.

Q10. What is LAN?

Ans. A LAN connects devices within a limited geographical area, such as a single room, a home, or an office building. It offers high data transfer speeds and is usually owned and managed by a single organization.

Example: A school computer lab or a home Wi-Fi network.

PART – B

Q11. Explain the features of UNIX Operating System.

Ans. UNIX is a powerful, multi-user, and multi-tasking operating system that has served as the blueprint for much of modern computing (including Linux and macOS).

Features of UNIX operating system:

1. Multi-user and Multi-tasking - UNIX allows multiple users to access system resources simultaneously while keeping their data and processes isolated. Furthermore, it supports multi-tasking, meaning a single user can run several programs at once in the background while continuing to work in the foreground.

2. Hierarchical File System - UNIX organizes data in a logical, tree-like structure. It starts at a single point called the root (represented by /), and everything from documents to hardware devices, is treated as a file within this hierarchy. This consistency makes it much easier for the system to manage diverse types of data.

3. The Kernel and the Shell - The system is split into two primary layers. Kernel is the "brain" of the OS that interacts directly with the hardware to manage memory, files, and CPU time.

And Shell is The command-line interface that acts as an intermediary between the user and the kernel. It interprets your commands and passes them to the system to be executed.

4. Portability - Unlike many early operating systems written in assembly language for specific machines, UNIX was rewritten in the C programming language. This makes it highly portable, allowing it to be moved (ported) to different hardware architectures with minimal changes to the code.

5. Pipes and Filters - UNIX encourages a "modular" approach to computing. Using pipes (represented by the | symbol), users can take the output of one small, specialized program and feed it directly as input into another. This allows users to build complex tools out of simple, reliable building blocks.

Q12. Write the features of Electronic Spread Sheet.

Ans. An electronic spreadsheet is a computer program that organizes data in a grid of rows and columns, allowing users to store, analyse, and calculate numerical and textual information using formulas and functions. These digital worksheets act as interactive tables for managing large datasets and performing complex analyses.

Common examples include: Microsoft Excel and Google Sheets.

Features of an electronic spreadsheet are as follows:

  1. Grid Layout – It’s made up of tiny boxes (called cells) arranged in rows and columns. You can type anything into these boxes; numbers, words, or formulas.
  2. Automatic Calculations – Just enter a formula (like `=A1 + A2`) and the spreadsheet does the math for you instantly. It updates the result automatically if you change the numbers.
  3. Formulas and Functions – Spreadsheets have built-in tools to do all kinds of tasks: adding numbers, finding averages, checking if something is true or false, counting items, and way more.
  4. Data Organization – You can neatly organize lists like to-do items, sales records, or monthly expenses. You can even sort them alphabetically, by size, or by date to make things easier to understand.
  5. Charts and Graphs – Spreadsheets can turn your data into colourful, easy-to-read visuals, like bar charts, line graphs, and pie charts, so you can spot trends or explain your point more clearly.
  6. Cell Referencing – Instead of copying and pasting numbers everywhere, spreadsheets can refer to other cells. That means if one number changes, any related calculations update automatically.
  7. Data Filtering and Sorting – Got a huge list? You can filter it to see only what you need; like all the items sold in June, or the names starting with “A.” Sorting helps you put things in order too, from smallest to largest, A to Z, etc.
  8. Conditional Formatting – You can tell the spreadsheet to highlight things for you. For example, “Make any cell red if the number is below 50.”
  9. Multiple Sheets in One File – A spreadsheet file can have different "pages" (called sheets). It’s like a notebook with many tabs, one for budgets, one for plans, one for notes, all in one place.
  10. Collaboration and Sharing – With tools like Google Sheets, many people can work on the same spreadsheet at once from different locations. You can leave comments, make suggestions, or see changes in real time.
  11. Data Validation – You can control what kind of data gets entered; like forcing a column to only accept dates or numbers between 1 and 100. This helps avoid errors.
  12. Templates – There are ready-made templates for budgets, schedules, invoices, and more, making your job more convenient and easier.

Q13. Explain the types of Data Transmission.

Ans. Movement of data in form of bits between two devices is data transmission. When we enter data into the computer via keyboard, each keyed element is encoded by the electronics within the keyboard into an equivalent binary coded pattern, using one of the standard coding schemes that are used for the interchange of information.

Types of Data Transmission:

Types of Data Transmission include: -

  1. Parallel Transmission
  2. Serial Transmission
  • Synchronous
  • Asynchronous
  1. Parallel Transmission:

Within a computing or communication device, the distances between different subunits are too short. Thus, it is normal practice to transfer data between subunits using a separate wire to carry each bit of data. There are multiple wires connecting each sub-unit and data is exchanged using a parallel transfer mode. This mode of operation results in minimal delays in transferring each word.

In parallel transmission, all the bits of data are transmitted simultaneously on separate communication lines. In order to transmit n bits, n wires or lines are used. Thus each bit has its own line. All n bits of one group are transmitted with each clock pulse from one device to another i.e. multiple bits are sent with each clock pulse.

Parallel transmission is used for short distance communication.

Advantage of Parallel Transmission –

It is speedy way of transmitting data as multiple bits are transmitted simultaneously with a single clock pulse.

Disadvantage of Parallel Transmission –

It is costly method of data transmission as it requires n lines to transmit n bits at the same time.

  1. Serial Transmission:

When transferring data between two physically separate devices, especially if the separation is more than a few kilometres, for reasons of cost, it is more economical to use a single pair of lines. Data is transmitted as a single bit at a time using a fixed time interval for each bit. This mode of transmission is known as bit- serial transmission.

In serial transmission, the various bits of data are transmitted serially one after the other.

It requires only one communication line rather than n lines to transmit data from sender to receiver.

Thus all the bits of data are transmitted on single line in serial fashion. In serial transmission, only single bit is sent with each clock pulse.

Advantage of Serial Transmission –

Use of single communication line reduces the transmission line cost by the factor of n as compared to parallel transmission.

Disadvantages of Serial Transmission –

  1. Use of conversion devices at source and destination end may lead to increase in overall transmission cost.
  2. This method is slower as compared to parallel transmission as bits are transmitted serially one after the other.

Types of Serial Transmission:

Serial Transmission is further categorised as –

  • Synchronous
  • Asynchronous

Both these transmissions use 'Bit synchronization'.

Bit Synchronization is a function that is required to determine when the beginning and end of the data transmission occurs. It helps the receiving computer to know when data begin and end

during a transmission. Therefore, bit synchronization provides timing control.

  1. Asynchronous Transmission:

Asynchronous transmission sends only one character at a time where a character is either a letter of the alphabet or number or control character i.e. it sends one byte of data at a time. Bit synchronization between two devices is made possible using start bit and stop bit. Start bit indicates the beginning of data i.e. alerts the receiver to the arrival of new group of bits. A start bit usually 0 is added to the beginning of each byte. Stop bit indicates the end of data i.e. to let the receiver know that byte is finished, one or more additional bits are appended to the end of the byte. These bits, usually 1s are called stop bits. Addition of start and stop increase the number of data bits. Hence more bandwidth is consumed in asynchronous transmission.

There is idle time between the transmissions of different data bytes. This idle time is also known as Gap. The gap or idle time can be of varying intervals. This mechanism is called Asynchronous, because at byte level sender and receiver need not to be synchronized. But within each byte, receiver must be synchronized with the incoming bit stream.

Applications of Asynchronous Transmission –

  1. Asynchronous transmission is well suited for keyboard type-terminals and paper tape devices. The advantage of this method is that it does not require any local storage at the terminal or the computer as transmission takes place character by character.
  2. Asynchronous transmission is best suited to Internet traffic in which information is transmitted in short bursts. This type of transmission is used by modems.

Advantages of Asynchronous Transmission –

  1. This method of data transmission is cheaper in cost as compared to synchronous e.g. If lines are short, asynchronous transmission is better, because line cost would be low and idle time will not be expensive.
  2. In this approach each individual character is complete in itself, therefore if character is corrupted during transmission, its successor and predecessor character will not be affected.
  3. It is possible to transmit signals from sources having different bit rates.
  4. The transmission can start as soon as data byte to be transmitted becomes available.
  5. Moreover, this mode of data transmission in easy to implement.

Disadvantages of Asynchronous Transmission –

  1. This method is less efficient and slower than synchronous transmission due to the overhead of extra bits and insertion of gaps into bit stream.
  2. Successful transmission inevitably depends on the recognition of the start bits. These bits can be missed or corrupted.
  1. Synchronous Transmission:

Synchronous transmission does not use start and stop bits. In this method bit stream is combined into longer frames that may contain multiple bytes. There is no gap between the various bytes in the data stream. In the absence of start & stop bits, bit synchronization is established between sender & receiver by 'timing' the transmission of each bit. Since the various bytes are placed on the link without any gap, it is the responsibility of receiver to separate the bit stream into bytes so as to reconstruct the original information. In order to receive the data error free, the receiver and sender operates at the same clock frequency.

Application of Synchronous Transmission –

Synchronous transmission is used for high speed communication between computers.

Advantage of Synchronous Transmission –

This method is faster as compared to asynchronous as there are no extra bits (start bit & stop bit) and also there is no gap between the individual data bytes.

Disadvantages of Synchronous Transmission –

  1. It is costly as compared to asynchronous method. It requires local buffer storage at the two ends of line to assemble blocks and it also requires accurately synchronized clocks at both ends. This lead to increase in the cost.
  2. The sender and receiver have to operate at the same clock frequency. This requires proper synchronization which makes the system complicated.

Q14. Explain any four mathematical functions in MS-Excel

Ans. MS Excel functions are powerful tools used to perform calculations, manipulate data, and automate tasks. Four mathematical functions which are:

1. SUM

The SUM function adds all the numbers in a specific range of cells. It is the most frequently used function for totaling data.

Syntax: =SUM(number1, [number2], ...)

Example: =SUM(A1:A10) adds all the values from cell A1 through A10.

2. AVERAGE

The AVERAGE function calculates the arithmetic mean of a group of numbers. It adds the numbers together and then divides by the count of those numbers.

Syntax: =AVERAGE(number1, [number2], ...)

Example: If cells B1, B2, and B3 contain 10, 20, and 30, =AVERAGE(B1:B3) will result in 20.

3. MIN and MAX

While these are technically statistical, they are essential "math" functions used to find the extremes in a dataset.

  • MAX: Returns the largest value in a set.
  • MIN: Returns the smallest value in a set.

Example: =MAX(C1:C100) will find the highest sales figure in a column of 100 entries.

4. ROUND

The ROUND function is used to round a number to a specified number of digits. This is particularly useful for financial data where you only want two decimal places.

Syntax: =ROUND(number, num_digits)

Example: =ROUND(15.6789, 2) will result in 15.68.

PART – C

Q15. What is Formatting? Explain the tasks which can be done in Formatting.

Ans. Microsoft Excel is a spreadsheet application for creating tables to store, organize, and analyse numerical and statistical data using formulas and functions. It features a grid of cells organized in rows and columns, where data can be entered and manipulated to perform calculations, create charts, and visualize information.

Formatting in MS Excel:

Formatting refers to changing the appearance of data and the spreadsheet layout without changing the actual data itself. Its purpose is to make the worksheet more readable and professional.

Adjusting Column Width and Row Height:

Steps to adjust column width include: -

  1. Point to the column header’s right border until the pointer changes to a plus sign, with arrows pointing towards West and East direction.
  2. Click and drag to the left or right to adjust the width. A dotted line appears as you drag, showing you where the new column border will be.

Alternatively,

Right-click the column header, select Column Width from the contextual menu, and enter the column width.

Or, select the column header, click the Format button in the Cells group on the Home tab, select Width, and enter column width.

Steps to adjust row height include: -

  1. Point to the row header’s bottom border until the pointer changes to a plus sign, with arrows pointing towards North and South direction.
  2. Click and drag up or down to adjust the height. A dotted line appears as you drag, showing you where the new row border will be.

Alternatively,

Right-click the row header, select Row Height from the contextual menu, and enter the row height.

Or, select the row header, click the Format button in the Cells group on the Home tab, select Height, and enter the row height.

Hiding/Unhiding Rows and Columns:

You can hide rows, columns, worksheets and entire workbook windows from view. Data isn’t deleted, but simply hidden from view until you unhide it.

Steps to hide a row or column include: -

  1. Select the row or column heading for the row or column you want to hide.
  2. Right-click the heading and select Hide from the contextual menu.

The row or column is hidden.

Alternatively,

  1. Select the row or column heading for the row or column you want to hide.
  2. On the Home tab, click the Format button in the Cells group.
  3. Point to Hide & Unhide and select Hide Rows or Hide Columns.

Steps to unhide a row or column include: -

  1. Select the row or column heading on both sides of the hidden row or column.

For example, if columns C and D were hidden, you would select the B and E column headings.

  1. Right-click the heading and select Unhide from the contextual menu.

Alternatively,

  1. Select the row or column heading on both sides of the hidden row or column.
  2. On the Home tab, click the Format button in the Cells group.
  3. Point to Hide & Unhide and select Unhide Rows or Unhide Columns.

Aligning a Worksheet Data:

Steps to align worksheet data include: -

  1. Select your desired cells.
  2. Go to the Home tab.
  3. Use the Alignment group icons to choose between –
  • Top Align, Middle Align, or Bottom Align for vertical positioning, and
  • Align Text Left, Centre, or Align Text Right for horizontal positioning.

Alternatively,

  1. Select your desired cells.
  2. Right-Click the selected cells.
  3. Select Format Cells. Format Cells Dialog Box appears.
  4. Click on Alignment Tab.
  5. Perform changes as per your requirement.
  6. Click OK.

Q16. What is Chart? Describe the components of a Chart. Also describe various types of Chart.

Ans. Charts in Microsoft Excel are visual tools that turn numerical data into easy-to-understand graphics. They help users quickly spot patterns, compare values, and track changes over time without reading long tables. Excel offers different chart types, such as column, line, pie, and bar charts, so data can be presented in the most suitable way. Using charts makes data analysis clearer, faster, and more effective.

Components of a Chart:

Components of a chart include: -

  1. Chart Area –
  • Chart Title: Gives the chart a name, describing the overall topic.
  • Plot Area: The rectangular region within the chart that contains the actual data points.
  1. Axes and Labels –
  • X-axis (Category Axis): The horizontal axis, typically displaying categories of data.
  • Y-axis (Value Axis): The vertical axis, showing numerical values.
  • Axis Titles: Text that explains what each axis represents.
  • Data Labels: Provide additional information, like the exact value, for a data marker.
  1. Data Visualisation –
  • Data Series: A set of related values that are plotted on the chart, such as all the bars or lines for one category.
  • Data Markers: The individual symbols on the chart that represent a single data value (e.g., a bar, dot, or slice of a pie).
  1. Supporting Elements –
  • Legend: Identifies the colours or patterns used to represent different data series.
  • Gridlines: Horizontal or vertical lines extending across the plot area, making it easier to read values.
  • Trendlines: Lines added to a chart to show a trend in the data, such as a moving average.

Types of a Chart:

Various types of charts in MS Excel include: -

  1. Column Chart - Column charts are used when you want to compare different values vertically side-by-side. Each value is represented in the chart by a vertical bar. If there are several series, each series is represented by a different colour.
  2. Line Chart - Line charts are used to illustrate trends over time. Each value is plotted as a point on the chart and is connected to other values by a line. Multiple items are plotted using different lines.
  3. Pie Chart - Pie charts are useful for showing values as a percentage of a whole. The values for each item are represented by different colours. Limit pie charts to eight sections.
  4. Bar Chart - Bar charts are just like column charts, except they display information in horizontal bars rather than in vertical columns.
  5. Area Chart - Area charts are the same as line charts, except the area beneath the lines is filled with colour.
  6. XY (Scatter) Chart - Scatter charts are used to plot clusters of values using single points. Multiple items can be plotted by using different coloured points or different point symbols.
  7. Stock Chart - Stock charts are effective for reporting the fluctuation of stock prices, such as the high, low, and closing points for a certain day.
  8. Surface Chart - A surface chart is useful for finding optimum combinations between two sets of data. Colours and patterns indicate values that are in the same range.
  9. Doughnut Chart - A doughnut chart shows the relationship of parts to a whole, but it can contain more than one data series.
  10. Bubble Chart - Bubble charts are similar to XY Scatter charts, but they compare three sets of values instead of two, with the third set determining the size of the bubble.
  11. Radar Chart - Radar charts compare the aggregate values of a number of data series.

Creating Charts:

Steps to create/insert a chart are as follows: -

  1. Make sure the cell range containing the data and labels you want to chart are selected.
  2. Click the Insert tab on the Ribbon. In the Charts group, there are several chart types to choose from. Each of the chart types then has several charts to choose from.
  3. Click a chart type button in the Charts group. A list of charts for the selected chart type appears.
  4. Select the chart you want to use from the list. The chart appears in the worksheet and the Chart Tools appear on the Ribbon. The Chart Tools include three new tabs (Design, Layout and Format) that help you modify and format the chart.

Q17. Explain various components of Multimedia.

Ans. The term Multimedia is a linguistic blend of two words: "Multi," meaning many, and "Media," referring to the material or medium through which information is transmitted or sent. It is defined as the integration of various media elements, such as text, graphics, audio, and video, to present information in a more effective, engaging, and attractive manner.

Components of Multimedia

Multimedia is comprised of five primary elements that work in synergy to represent data:

  1. Text

The most common medium for representing information It is primarily utilised for titles, headlines, and navigation menus.

Common extensions include .DOC and .TXT.

Software: Microsoft Word, Notepad, and WordPad.

  1. Audio

Encompasses speech and music to increase the "understandability" and clarity of concepts. The MP3 format is the industry standard for storing compressed sound and music.

Software: QuickTime, RealPlayer, and Windows Media Player.

  1. Graphics

The foundation of every multimedia presentation, making concepts more presentable and professional. Often viewed via Windows Picture viewer or web browsers like Internet Explorer.

Software: Adobe Photoshop is a leading tool for editing graphics to make them more attractive.

  1. Video

A combination of moving pictures with synchronized sound. It is considered the most effective way to communicate, as it saves time and enhances presentation. The MPEG (Moving Pictures Experts Group) format is widely used for video files.

  1. Animation

The process of altering images in a sequence so they appear as moving pictures to the human eye. It shows a specific number of frames per second to produce the effect of motion.

Q18. What is Networking? Describe various types of Networking.

Ans. Computer networking refers to the practice of connecting two or more computers or electronic devices (nodes) together for the purpose of sharing resources, exchanging files, or allowing electronic communications. These connections are established using either wired media (like Ethernet cables) or wireless media (like Wi-Fi).

In a network, devices use a set of common communication protocols to transmit data over digital interconnections. This system allows for the centralized management of data, increased storage capacity, and efficient resource sharing (such as printers and internet connections).

Classification by Geographical Area:

1. PAN (Personal Area Network)

A PAN is the smallest type of network, typically used by a single person within a very small range (about 10 meters). It connects personal devices like smartphones, tablets, and smartwatches.

Example: Connecting a Bluetooth headset to a phone or syncing a smartwatch.

2. LAN (Local Area Network)

A LAN connects devices within a limited geographical area, such as a single room, a home, or an office building. It offers high data transfer speeds and is usually owned and managed by a single organization.

Example: A school computer lab or a home Wi-Fi network.

3. MAN (Metropolitan Area Network)

A MAN covers a larger area than a LAN but is smaller than a WAN. It typically connects multiple LANs across a city or a large campus.

Example: A cable TV network or a city-wide public Wi-Fi system.

4. WAN (Wide Area Network)

A WAN spans a large physical distance, such as a country, a continent, or even the entire globe. It uses leased telecommunication lines, fiber optics, or satellites to link smaller networks together.

Example: The Internet is the largest and most well-known WAN.

Classification by Topology:

A Network Topology is the arrangement with which computer systems or network devices are

connected to each other. Topologies may define both physical and logical aspect of the network. Both logical and physical topologies could be same or different in a same network.

Types of Network Topology –

Various types of network topologies include: -

  1. Point-to-Point Topology –

Point-to-point networks contains exactly two hosts such as computer, switches or routers, servers connected back to back using a single piece of cable. Often, the receiving end of one host is connected to sending end of the other and vice-versa.

If the hosts are connected point-to-point logically, then may have multiple intermediate devices. But the end hosts are unaware of underlying network and see each other as if they are connected directly.

  1. Bus Topology –

In case of Bus topology, all devices share single communication line or cable. Bus topology may have problem while multiple hosts sending data at the same time. Therefore, Bus topology either uses CSMA/CD technology or recognizes one host as Bus Master to solve the issue. It is one of the simple forms of networking where a failure of a device does not affect the other devices. But failure of the shared communication line can make all other devices stop functioning.

Both ends of the shared channel have line terminator. The data is sent in only one direction and as soon as it reaches the extreme end, the terminator removes the data from the line.

  1. Star Topology –

All hosts in Star topology are connected to a central device, known as hub device, using a point to-point connection. That is, there exists a point to point connection between hosts and hub. The hub device can be any of the following:

  • Layer-1 device such as hub or repeater
  • Layer-2 device such as switch or bridge
  • Layer-3 device such as router or gateway

As in Bus topology, hub acts as single point of failure. If hub fails, connectivity of all hosts to all other hosts fails. Every communication between hosts, takes place through only the hub. Star topology is not expensive as to connect one more host, only one cable is required and configuration is simple.

  1. Ring Topology –

In ring topology, each host machine connects to exactly two other machines, creating a circular network structure. When one host tries to communicate or send message to a host which is not adjacent to it, the data travels through all intermediate hosts. To connect one more host in the existing structure, the administrator may need only one more extra cable. Failure of any host results in failure of the whole ring. Thus, every connection in the ring is a point of failure. There are methods which employ one more backup ring.

  1. Mesh Topology –

In this type of topology, a host is connected to one or multiple hosts. This topology has hosts in point-to-point connection with every other host or may also have hosts which are in point-to point connection to few hosts only.

Hosts in Mesh topology also work as relay for other hosts which do not have direct point-to point links.

Mesh technology comes into two types:

  • Full Mesh: All hosts have a point-to-point connection to every other host in the network. Thus for every new host n(n-1)/2 connections are required. It provides the most reliable network structure among all network topologies.
  • Partially Mesh: Not all hosts have point-to-point connection to every other host. Hosts connect to each other in some arbitrarily fashion. This topology exists where we need to provide reliability to some hosts out of all.
  1. Tree Topology –

Also known as Hierarchical Topology, this is the most common form of network topology in use presently. This topology imitates as extended Star topology and inherits properties of bus topology.

This topology divides the network in to multiple levels/layers of network. Mainly in LANs, a network is bifurcated into three types of network devices. The lowermost is access-layer where computers are attached. The middle layer is known as distribution layer, which works as mediator between upper layer and lower layer. The highest layer is known as core layer, and is central point of the network, i.e. root of the tree from which all nodes fork.

All neighbouring hosts have point-to-point connection between them. Similar to the Bus topology, if the root goes down, then the entire network suffers. Even though it is not the single point of failure. Every connection serves as point of failure, failing of which divides the network into unreachable segment.

  1. Daisy Chain –

This topology connects all the hosts in a linear fashion. Similar to Ring topology, all hosts are connected to two hosts only, except the end hosts. Means, if the end hosts in daisy chain are connected then it represents Ring topology.

Each link in daisy chain topology represents single point of failure. Every link failure splits the network into two segments. Every intermediate host works as relay for its immediate hosts.

  1. Hybrid Topology –

A network structure whose design contains more than one topology is said to be hybrid topology. Hybrid topology inherits merits and demerits of all the incorporating topologies.

The combining topologies may contain attributes of Star, Ring, Bus, and Daisy-chain topologies. Most WANs are connected by means of Dual-Ring topology and networks connected to them are mostly Star topology networks. Internet is the best example of largest Hybrid topology.

Classification by Network Architecture:

  1. Client-Server Network: A powerful central computer (server) provides resources to less powerful computers (clients).
  2. Peer-to-Peer (P2P) Network: Every computer has equal status and shares resources directly without a central server.