Trending November 2023 # Learn The Architecture Of Firewall In Detail # Suggested December 2023 # Top 20 Popular

You are reading the article Learn The Architecture Of Firewall In Detail updated in November 2023 on the website We hope that the information we have shared is helpful to you. If you find the content interesting and meaningful, please share it with your friends and continue to follow and support us for the latest updates. Suggested December 2023 Learn The Architecture Of Firewall In Detail

Introduction to Firewall

Start Your Free Software Development Course

Web development, programming languages, Software testing & others

The basic concept of a firewall is to protect the internal or organizational environment from any external security attack. Similarly, three major aspects will define the firewall’s configuration, like the network’s objective regarding the organization’s point of view, the development ability, and how we need to implement it. While considering it in terms of the hardware level, then we need to consider the budget also.

Firewall Architecture in Detail

There are different types of architecture available in the firewall.

1 Screened host firewall architecture

We have improved the packet filtering routers firewall architecture in the screened host firewall architecture. In this architecture, we use the packet filtering routers firewall technique with the dedicated or the separate firewall. It is known as the application proxy server. In the packet filtering router’s firewall architecture, we have a very big overhead to filter the network traffic (once the access control list increases). Due to this, we are facing lots of issues. Here, we have tried to overcome it and added a dedicated firewall. This technique will allow the router to access the firewall. Due to this architecture, the routers will pre-screen the network traffic or the packets to minimize the network overhead. It will also help to distribute the load as well.

Work Flow: As per the above architecture, a separate host is available, i.e., the bastion host. It acts like a proxy server to balance the load on the firewall. The firewall holds all the set of rules and access control. The Bastion server will help to filter out the network traffic. If it is a valid packet, it will allow it via proxy access to the internal filter router, moving further in the internal network.

2. Packet filtering routers’ firewall architecture

Many organizations want internet connectivity. If we enable internet connectivity, the organization without a firewall will be exposed to the external world. We need to install and configure the firewall to avoid an external security attack. In the packet filtering routers, we have the router concept. Here, the router interface acts as the internet provider to the organization. The router acts as an intermediate between the organization and the internet provider. On the same level, we are enabling the network packet filtering process.

If any unwanted packets may come, so it will filter them out on the same level. Hence the packages will drop or be rejected. It will not come in the organization-level network. It is a very simple way to implement it. It will also help to lower the risk of external security threats. But it has a few concerns also. If we go with the packet filtering routers, there will be less auditing of the network traffic. Similarly, we are also having the drawback of the strong authentication mechanism. Day by day, the access control list will grow. Hence, it will be a very big overhead to filter the incoming network packets. Due to this, it will decrease the network performance also. In a few cases, we will face a lag.

Work Flow: It is the basic technique to implement the firewall. Here, the ISP will provide an internet connection to the organization. Then, it is attached to the external filter router. First, we need to add the list of ACLs and configurations on the firewall. Then, with the help of the same configuration, the network traffic will filter and pass to the internal filter router. Further, the internal filter router will separate the network traffic into the internal organization-level network.

3. Dual-homed firewall architecture

The architectural complexity is increasing because we need high performance and less network lag. We use the single network interphase card in the previous firewall architecture. But when using such firewall architecture, the bastion host will contain the two different network interphase cards. In this architecture, one network interphase card will connect with the external network, and the other will connect with the internal network. Here, all the network traffic will physically travel from the firewall between internal and external network interphase cards.

Work Flow: In this architecture, there is no separate proxy server. In this firewall architecture, there are two different NIC’s available. In one NIC, the external ISP connection will connect. In the second NIC, the internal network will connect. Once the traffic comes, the firewall will filter the traffic and pass it to the internal network. If the traffic is not valid, the firewall will drop the packet and not flow it further.


We have seen the uncut concept of the “firewall architecture” with the proper explanation. Several firewall architectures are available; we must choose them per our requirements and budget. The firewall will track the traffic on the application level also.

Recommended Articles

We hope that this EDUCBA information on “Firewall Architecture” was beneficial to you. You can view EDUCBA’s recommended articles for more information.

You're reading Learn The Architecture Of Firewall In Detail

Learn The Working Of The Math Library In Lua

Introduction to Lua math

In Lua, math is defined as a standard library that consists of mathematical functions that are used in Lua programs for dealing with mathematical concepts easily by declaring this library in the program. In general, Lua math is a standard library provided by Lua programming language to work with mathematical concepts using the functions that are defined in this library for solving mathematical related problems such as logarithmic functions (log), exponential functions (exp), trigonometric functions (sin, cos, tan, etc), rounding functions (floor, ceil) and many other functions like max, min, pi, etc are defined within this Lua math library which is an interface to standard C math library.

Start Your Free Software Development Course


math.function_name(argument_list or parameter);

In the above syntax, we can when we want to use any math functions then we need to use math library provided by Lua standard library and to define or use any kind of math functions then we have to use math library starting with math then followed by a dot and then followed by the function name along with the parameters that need to be declared or used in the function for calculations.

Working of math library in Lua programming language

The Lua math library can be included directly with its function name and the parameters are passed to this function to include the variable values that are needed to calculate according to the function defined. In Lua, there are various functions for different mathematical calculations in the math library and a few of them are listed in the below section. But before that, we will see a list of math functions that are defined within this math library.

math.sin(x), math.cos(x), math.tan(x), math.asin(x), math.acos(x), etc are some of the trigonometric functions for getting sine, cosine and tangent for radiant values that are passed as parameter to the function and asin and acos are for getting arc sine and arc cosine in radians for the given values in the parameter.

In Lua, the math library also provides random functions such as math.random([x [,y]]) to get random numbers.


In the below example let us see few math functions demonstration using math library.

print( "Demonstration of math library function in Lua programming language ") print("n") print("Rounding functions in math library are as follows:") a = 89.50983 print(" The floor value of a is ", math.floor(a)) print(" The ceil value of a is ", math.ceil(a)) print("n") print(" Comparative function are as follows: ") print(" The maximum of the given numbers is : ", math.max(30, 46, 29, 78, 56, 9)) print(" The minimum of the given numbers is : ",math.min(30, 46, 29, 78, 56,9)) print("n") print(" The trigonometric functions provided in the math library is as follows: ") print("n") p = math.rad(math.pi / 2) print("The pi value for calculating trigonometric values is : ", p) print("n") print("The sine value of the given radian which is 90 degree is : ", string.format("%.1f ", math.sin(p))) print("The cosine value of the given radian which is 90 degree is : ", string.format("%.1f ", math.cos(p))) print("The tangent value of the given radian which is 90 degree is : ", string.format("%.1f ", math.tan(p))) print("The sine hyperbolic value of the given radian which is 90 degree is : ", string.format("%.1f ", math.sinh(p))) print("The cosine hyperbolic value of the given radian which is 90 degree is : ", string.format("%.1f ", math.cosh(p))) print("The tangent hyperbolic value of the given radian which is 90 degree is : ", string.format("%.1f ", math.tanh(p)))


In the above program, we can see some of the math functions that are defined using the math library in the program. In the first we are finding the rounding of functions such as math.floor() which will round of to the previous value and math.ceil() will round off the value to the next value of the given number. Then we are defining comparative functions such as max and min which will display the maximum and minimum number in the given list of the numbers as parameters to this function. Then we have defined few trigonometric functions and to display the values for the radian with 90 degrees where we have converted the pi value to the radian value using rad() such as math.rad(math.pi / 2), whereas if we want to display the degree value then we can use deg() function as math.deg(math.pi / 2). In the above program, we have displayed the values of sine, cosine, and tangent along with its hyperbolic values also. The output of all these functions can be seen in the above screenshot.


print( "Demonstration of some other math library function in Lua programming language ") print("n") print("The squareroot of given number a is :", math.sqrt(24)) print("n") print("The 2 to the power of 5 is :", math.pow(2,5)) print("n") print("The absolute value of the given number is :", math.abs(-45)) print("n") print("The exponential value of the given number is :", math.exp(4)) print("n") print("The logarithmic value of the given number is :",math.log(2)) print("n") print("Random number between 70 and 80 is ",math.random(70,80))


In the above program, we can see we have defined some other math function provided by the math library such as math.sqrt() will display the square root of the specified number, math.pow() will specify the powers of the given number in the above program, it is 2 ^ 5 =32, then we saw math.abs() which will display the absolute value which will always display positive number, then math.exp() will display the exponential value, math.log() displays logarithmic values, then we have also defined the math.random() function to display the random number. The output in the above screenshot will show the result of these functions respectively.


In this article, we conclude that Lua provides a standard library that contains mathematical functions for some mathematical calculations in the program and it is provided by the math library. In this, we don’t need to separately import or include the math library we can directly use it with the math function with a dot followed by the math function name. Therefore unlike other programming languages, this also has a simple math library for mathematical operations.

Recommended Articles

We hope that this EDUCBA information on “Lua math” was beneficial to you. You can view EDUCBA’s recommended articles for more information.

Top 10 Components Of Iot Architecture In 2023

In this article, we aim to examine the concept of IoT architecture, explain the difference between IoT ecosystem and IoT architecture, demonstrate its ten different components, and finally provide a real-life example for contextualization.

What is IoT architecture?

IoT architecture comprises several IoT building blocks connected to ensure that sensor-generated data is collected, transferred, stored, and processed in order for the actuators to perform their designated tasks.

What is the difference between IoT ecosystem and IoT architecture?

IoT ecosystem is the encompassing term attributed to the five general components of devices, communication protocols, the cloud, monitoring, and the end-user in the IoT system.

IoT architecture is the breakdown of the inner workings of these building blocks to make the ecosystem function.

What are the different elements of IoT architecture?

For the sake of brevity, we will only explore the ten most important parts of an IoT architecture.

1- Devices

IoT devices are equipped with sensors that gather the data, which will be transferred over a network. The sensors do not necessarily need to be physically attached to the equipment. In some instances, they are remotely positioned to gather data about the closest environment to the IoT device. Some examples of IoT devices include:

Temperature detectors

Smoke detectors

Cameras and CCTVs

2- Actuators

Actuators are devices that produce motions with the aim of carrying out preprogrammed tasks, for example:

Smart lights turning on or off

Smart locks opening or closing

Thermostat increasing or decreasing the temperature

3- Gateways 4- Cloud gateways 5- Data lake

A data lake is a data storage space that stores all sorts of structured and non-structured data such as images, videos, and audio, generated by IoT devices, which will then be filtered and cleaned to be sent to a data warehouse for further use.

6- Data warehouse

For meaningful insight, data should be extracted from the data lake to the data warehouse, either manually, or by using data warehouse automation tools. A data warehouse contains cleaned, filtered, and mostly structured information, which is all destined for further use.

7- Data analytics

Data analytics is the practice of finding trends and patterns within a data warehouse in order to gain actionable insights and make data-driven decisions about business processes. After having been laid out and visualized, data and IoT analytics tools help identify inefficiencies and work out ways to improve the IoT ecosystem.

8- Control applications

Previously, we mentioned how actuators make “actions” happen. Control applications are a medium which, through them, it’s possible to send out the relevant commands and alerts which will make actuators function. An example of a control application could be soil sensors signaling a dryness in the lawns, and consequently, the actuators turning on the sprinkles to start irrigation.

9- User applications

They are software components (e.g. smartphone apps) of an IoT system that allow users to control the functioning of the IoT network. User applications allow the user to send commands, turn the device on or off, or access other features.

10- Machine learning

Machine learning, if available, gives the opportunity to create more precise and efficient models for control applications. ML models pick up on patterns in order to predict future outcomes, processes, and behavior by making use of historical data that’s accumulated in the data warehouse. Once the applicability and efficiency of the new models are tested and approved by data analysts, new models are adopted.

What is a real-life example IoT architecture?

The sensors take relevant data, such as daylight or people’s movement. The lamps on the other end, are equipped with actuators to switch the light on and off. The data lake stores these raw data coming from the sensors, while a data warehouse houses the inhabitants’ behavior on various days of the week, energy costs, and more. All these data, through field and cloud gateways, are transferred to computing databases (on-premise or cloud).

The users have access to the user application through an app. The app allows them to see which lights are on and off, or it gives them the ability to pass on commands to the control applications. If there is a gap in algorithms, such as when the system mistakenly switches off the lights and the user has to switch it on manually, data analytics can help address these problems at its core.

When daylights get lower than the established threshold, it’s the control applications commanding the actuators to turn the lights on. At other times, if the lights are on power-saving mode and would only be turned on if a user walks past the lawn, it’s the cloud that receives the data of a passerby walking and after identification, alerts the actuators to turn the lights on. This makes sure that false alarms are detected and the power is conserved.

But the control application does not only function with already-established commands. By leveraging machine learning, algorithms would learn more about usage patterns and customize the functionality accordingly. For example, if the inhabitants leave home at 7 am and come back at 5 pm, after some time, the lights would turn off and on in between this interval autonomously. These smart adjustments would, furthermore, reduce the need for human intervention and make for seamless continuity.

For more on the internet of things

To learn more about the technical side of internet of things, read:

Finally, If you believe your business will benefit from an IoT solution, feel free to check our data-driven hub of IoT solutions and tools.

And we can guide you through the process:

He primarily writes about RPA and process automation, MSPs, Ordinal Inscriptions, IoT, and to jazz it up a bit, sometimes FinTech.





Learn The List Of Coreldraw Viewer

Introduction to CorelDraw Viewer

A CorelDraw Viewer is a program that helps the user to view the CorelDraw files without having to download the CorelDraw software. CorelDraw is a vector software that creates a specific file Extension .CDR.

.CDR is a file extension that cannot be viewed or opened on every software, just like the JPG format. To view the files with this extension, the user needs a definite program that helps them to do the same.

Start Your Free Design Course

3D animation, modelling, simulation, game development & others

List of CorelDraw Viewer

Some of the programs that help the user to view or edit .CDR files are finite but are either downloadable freeware programs or are available online instantly.

1. Imagine

This is a freeware program available in the market. The users can easily download the software and use it to view .CDR files. In addition, this program can create animations and batch sequence images as well. It is a useful program for graphic designers who are looking for open-source software. Following are the steps to view .CDR files:-

Download and install the software.

Open the software

Select the source folder where the .CDR file is saved to view the same

2. Inkscape

This program was created by SODIPODI developers. INKSCAPE is the successor of the Sodipodi program. This program is a vector graphics program, and it creates files in .SVG format (Scalable Vector Graphics). Other vector file formats such as .CDR can be viewed and edit within the software. The program proves to be functional and user-friendly. It has multiple features and can easily be used to create vector artworks.

Following are the steps to view .CDR files in the software:-

Download and install the program from the internet.

Open the CDR file. The program is also capable of modifying the artwork easily.

3. Irfan View

Following are the steps to view .CDR files in the software:-

Download and install the program from the internet.

Open the program

Select the CDR file that needs to be viewed

4. LibreOffice

To view a .CDR file, the user either needs CorelDraw Viewer or may convert the same file extension to other file formats. In this way, the user can view a .CDR file on any software.

One of the programs that help the user to convert the .CDR files to any other file format is Bit Recover CDR CONVERTER WIZARD.

Following are the steps through which the user can covert the .CDR files to any other file format.

Download and install Bit Recover CDR Converter wizard from the internet

Select the .CDR Files that you need to convert.

Select the File extension you need to convert the .CDR files to

Select the destination folder in which the files needs to be saved

This program will help the user to convert the existing .CDR files to any other file format. With the program .CDR files can also be viewed in Adobe Photoshop or Adobe Illustrator programs.


To view CorelDraw files, the user can use some of the methods that are listed above. Since CorelDraw is a paid and expensive program, not every user can afford to purchase the software. In such a case, the user can use the open-source freeware programs to view or edit graphic artworks as per their requirements.

Furthermore, these open-source programs can only be used for viewing and simple editing. For complex and detailed modifications, the user will have to purchase CorelDraw software.

Recommended Articles

This is a guide to CorelDraw Viewer. Here we discuss the list of CorelDraw viewers like Imagine, Inkscape, Irfan view, and LibreOffice in detail with an explanation. You may also have a look at the following articles to learn more –

Top 15 Components Of 8085 Architecture

Introduction to 8085 Architecture

Eighty-eighty-five is an 8-bit microprocessor created in 1971 by Intel. It requires less circuit and makes the computer system to be simpler and easy to be built. It uses 5-volt power supply and has depletion mode transistors. Hence, 8085 could be compared with 8080 derived CPU. Hence these can be used in the systems with CP/M operating system. It has a DIP package with 40 pins. There is a data bus in the processor to fully utilize the functions of pins. There is built in serial I/O and 5 interrupts so that 8085 has long life similar to the controller used.

Start Your Free Data Science Course

Architecture of 8085:

Components of 8085 Architecture

1. It consists of timing and control unit, accumulator, arithmetic and logic unit, general purpose register, program counter, stack pointer, temporary register, flag register, instruction register and decoder, controls, address buffer and address and data bus.

2. The timing and control unit provides proper signals to the microprocessor to perform functions in the system. We have control signals, status signals, DMA signals and RESET signals. This also controls the internal and external circuits in the system.

3. The accumulator is a register that performs all the arithmetic and logic operations in 8-bit processor. It connects the data bus and ALU unit of the processor.

4. ALU performs all the operations that includes arithmetic and logic operations such as addition, subtraction, multiplication, division, and the logical operations in the system.

5. General purpose registers used in the processor include B, C, D, E, H and L registers. Each register holds the data and also these could be made to work in pairs. Hence these can hold 16-bit data in the processor.

7. Stack pointer works like a stack with a 16-bit register. It performs push or pop operations and is either incremented or decremented by 2 in the register.

8. Temporary data of the operations in ALU is handled in a temporary register which is 8-bit.

9. The 8-bit register with 1-bit flip-flops is called Flag register. There are 5 flip-flops and it holds logic data from the accumulator register. The logic data can be 0 or 1. The five flip-flops are Sign, Zero, Auxiliary Carry, Parity and Carry.

10. Instruction register and decoder is also an 8-bit register where instructions are stored after taking it from the memory. Decoder encrypts the instruction stored in the register.

11. The signal is given to the microprocessor through the timing and control unit to do the operations. There are different time and control signals to perform the operations. They are control signals, status signals, DMA signals, and RESET signals.

13. Serial data communication is controlled using serial input data and serial output data.

14. Stack pointer and program counter load the data into the address buffer and data buffer so that it communicates with the CPU. The chips are connected here and CPU transfers data via these chips to the data buses.

15. Data to be stored is saved in the data bus and it transfers data to different address services.

Features of 8085 Architecture

Any 8-bit data could be processed, accepted, or provided in the microprocessor simultaneously. The power supply is a single 5-volt supply and operates on a 50% duty cycle.

The clock generator in the processor is internal that needs a tuned circuit, either LC or RC or crystal. The frequency is divided by 2 so that the clock signal is generated to synchronize external devices of the system.

3 MHz frequency can be used to operate the processor. The maximum frequency in which 8085 operates is 5 MHz

16 address lines are provided in the processor so that it can access 64 Kbytes of memory in the system. Also, 8 bit I/O addresses are provided to access 256 I/O ports.

The address bus and data bus in the processor is multiplexed so that the number of external pins can be reduced. External hardware is needed to separate the address and data lines in the processor. 74 instructions are supported in the processor with different address modes. The address modes are immediate, register, direct, indirect, and implied modes.


The general-purpose electronic processing devices in the system to execute various tasks are called the microprocessors. All the logic and arithmetic operations are performed here and the results are stored in the registers. This helps the CPU to fetch information whenever needed in the system.

Data could be fetched and moved easily to various locations with the help of registers in the microprocessor.

Operands are delivered easily from the microprocessor and this is easy to do than to restore the operands from the memory. Program variables are stored easily in the registers and hence developers prefer to work with processors in the system.

Serial communication is provided with serial control and hardware interrupts are available to deliver urgent requests. It handles the interruptions in a skilled manner so that the process is kept on hold until the urgent requests are fulfilled. Control signals are available so that bus cycles are controlled. This rule out the chance of an external bus controller.

The system bus is shared with Direct Memory Access to transfer huge data from device to memory or vice versa.

Trainer kits are provided in the institutions to learn about microprocessors so that complete documentation is provided to the students regarding the microprocessors. Also, simulators are available for the execution of the codes in the graphical interface. Assembly language programming is added in the microprocessor course so that it helps the students.

Recommended Articles

3D Color Images Of The Brain Reveal Its Glorious Unseen Detail

The human brain remains one of the most mysterious organs in the human body. However, an imaging technique tested on mice brains and developed by a group of researchers including from Harvard, MIT, and Boston University, may bring them one step closer to understanding the human brain’s intricacies. Their results were published yesterday in the journal, Cell.

The approach will allow scientists to see the brain’s beautifully layered 3D structure on the nanoscale with different colors to separate and distinguish cell types. They first created the 3D structure of a mouse dendrite by combining electron microscope (EM) images of the brain structure together. Then, they achieved the color differentiation using VAST, an annotation tool–developed at Harvard by a co-author of this study–that allows users to manually add color to EM images. This is the first time VAST was used to create color images of the brain.

The point of this study was simply to see what could be learned from seeing the brain, anatomized into its parts using different colors. But going forward, the researchers think this tool could be used to see what a neurological disorder actually looks like in the brain and how the human brain differs from that of other animals as well as how individual human brains differ from each other.

To see if the application would actually work, the researchers chose to visualize parts of a mouse’s neocortex–the area of the brain that receives sensory information from mouse whiskers, which are even more sensitive than human fingertips. They first took EM images of the structure, combined them, then, using VAST, they assigned different colors to piece apart the individual structures and cell types, allowing them to see each type individually and how they come together to create the brain structures. In the video below, they use color coordination to reconstruct the structures that surround two dendrites–the tree-like branches of a neuron that receive sensory information from other neurons. The objects are initially shown as they would appear in the brain. Then, they are sorted by category–axonal, dendritic, or glial–then further by functional type–excitatory or inhibitory for axons and dendrites and when applicable, by type of glial cell.

“The complexity of the brain is much more than what we had ever imagined,” said Narayanan Kasthuri, an assistant professor at Boston University School of Medicine and lead author of the study, in the press release.

Here’s a breakdown of the color-coordinated brain structures in .gif form:

However, despite the beauty of the finished product, whether or not the technique will actually be put to use is still up in the air. During their testing, the researchers found that the sheer magnitude of neuronal connections that make up the brain imposed a huge challenge–one that the authors conclude in their study made them question whether the finished product justifies its use. They write that their effort “lays bare the magnitude of the problem confronting neuroscientists who seek to understand the brain.” They also used a mouse’s brain and note that a human brain has far more neuronal complexity. But despite the brain’s so-called near impossible-to-understand intricacies, they remain hopeful: “In the nascent field of connectomics there is no reason to stop doing it until the results are boring.”

Update the detailed information about Learn The Architecture Of Firewall In Detail on the website. We hope the article's content will meet your needs, and we will regularly update the information to provide you with the fastest and most accurate information. Have a great day!