Forem: Palak Hirave

Network Address Translation (NAT)

Palak Hirave — Sun, 03 May 2026 04:51:33 +0000

As we have talked about before, the Internet relies on numerical addresses, IP addresses to route data from one device to another. IPv4 offers around 4.3 billion addresses, we have discussed that that is not enough. While there is IPv6, another solution to this issue is through Network Address Translation (NAT)

NAT allows multiple devices on a private network to share a single public IP address. This not only helps conserve the limited pool of public IP addresses but also adds a layer of security to the internal network.

Private vs. Public IP Addresses

Public IP addresses are globally unique identifiers that are assigned by Internet Service Providers (ISPs). Devices with these IP addresses can be accessed from anywhere on the Internet, allowing them to communicate across the global network.

On the other hand, private IP addresses are designated for use within local networks such as homes, offices and schools. These are not routable on the global internet, so they cannot be forwarded by internet backbone routers. Defined by RFC 1918, common IPv4 private address ranges include 10.0.0.0 to 10.255.255.255, 172.16.0.0 to 172.31.255.255, and 192.168.0.0 to 192.168.255.255. This setup ensures that these private networks operate independently of the internet while facilitating internal communication and device connectivity.

Private IP addresses contribute to conserving public IP addresses. Using Network Address Translation (NAT), a local network can utilize private IP addresses while sharing a single public IP address, reducing the number of public IPs needed. This setup makes devices accessible from the internet without using multiple public addresses. Additionally, private IPs help secure the network by isolating internal devices from direct exposure to the internet, protecting them from potential external threats.

How does it work?

Network Address Translation (NAT) is a process carried out by a router or a similar device that modifies the source or destination IP address in the headers of IP packets as they pass through. This modification is used to translate the private IP addresses of devices within a local network to a single public IP address that is assigned to the router.

For example, say that your home network has a few devices, laptop, smartphone, tablet and a smart thermostat. All of these have their own private IP addresses which they can use to connect to eachother. But when, suppose the laptop wants to access a DNS Server on the internet, it will need a public IP address. As the packet passes though the router, the router will change the private IP address into a public one. This public IP address is the same for all of the devices in the network. As the response arrives, the router's NAT table, which keeps track of IP mappings, identifies that 203.0.113.50:4444 corresponds to the laptop at 192.168.1.10:5555 (ports 4444 and 5555 are dynamic). All of this is done by the NAT process.

Types of NAT

Static NAT - Involves a one-to-one mapping, where each private IP address corresponds directly to a public IP address.

Dynamic NAT - Assigns a public IP from a pool of available addresses to a private IP as needed, based on network demand.

Port Address Translation (PAT) - Also known as NAT Overload, is the most common form of NAT in home networks. Multiple private IP addresses share a single public IP address, differentiating connections by using unique port numbers. This method is widely used in home and small office networks, allowing multiple devices to share a single public IP address for internet access.

Benefits and Trade-Offs

Benefits

Conserves the limited IPv4 address space.
Provides a basic layer of security by not exposing internal network structure directly.
Flexible for internal IP addressing schemes.

Trade-Offs

Complex services like hosting a public server behind NAT can require additional configuration (e.g., port forwarding).
NAT can break certain protocols that rely on end-to-end connectivity without special handling.
Adds complexity to troubleshooting connectivity issues.

DHCP - What is it?

Palak Hirave — Sun, 03 May 2026 04:18:45 +0000

DHCP stands for Dynamic Host Configuration Protocol. Rather than manually assigning IP addresses to devices when they join the network, DHCP does this on its own. Once a new device connects to the network, the DHCP is responsible for assigning in network configuration parameters such as subnet mask, default gateway, DNS servers, and an IP address. This saves time and effort as you do not have someone manually doing this every time a device joins the network. It also prevents human error. DHCP's recycle IP addresses when they are done being used. Eg. device has left the network, so its IP address is assigned to another device who needs one.

DHCP works via interactions between the server and client.

DHCP Server : A network device (router/dedicated server) that manages IP address allocation. It maintains a pool of available IP addresses and configuration parameters.

DHCP Client : Any device that connects to the network and requests network configuration parameters from the DHCP server.

You can use the acronym, DORA to remember how the process works.

Discover

When a device first connects to the network, it figures out where the DHCP Servers are located. It does this by broadcasting a DHCP Discover message.

Offer

A DHCP Server on the network sees this message and responds with an DHCP Offer message, which offers the client an IP address and lease.

Request

The client receives this message and responds with a DHCP Request message. This says that the client has accepted the given IP address and lease.

Acknowledgement

The server sends a DHCP Acknowledgement message which confirms that the client has been given an IP address, the client can start using this IP address to communicate on the network.

Now the device doesn't get to keep this lease and IP address forever. When the DHCP assigns the lease, it has been given with a certain amount of time, say 24 hours, and once that time is up the lease ends and you can no longer connect till you get a new one. You also lose your IP address as you will not be considered as part of the network. So, once the lease is coming to an end, the device sends out a DHCP Request, saying that its lease needs to be renewed and to continue with the same IP address. If possible, the DHCP responds with an DHCP Acknowledgement message saying that the lease has been renewed.

A simple example would be that Rebecca wants to connect to her office's network with a new device. The first thing the device will have to do in order to connect is send a DHCP Discover message. Once a DHCP Server sees it, it will respond with a DHCP Offer containing a lease and the IP address(e.g. 192.168.3.64). The device then accepts it with a DHCP Request message and the server responds with a DHCP Acknowledgement message. Once the time on the lease is starting to finish, the device sends another DHCP Request message in order to continue using it as well as the IP address.

Ports

Palak Hirave — Sat, 02 May 2026 04:28:15 +0000

A port is a number assigned to a specific process or sevice in the network to help comuters sort and direct network traffic correctly. It works on Layer 4(Transport Layer) of the OSI model and works with protocals such as TCP and UDP. They enable the simultaneous operaton of multiple network services on a single IP adress.

When a client application initiates a connection, it specifies the destination port number corresponding to the desired service. Client applications are those who request data or services while server applications respond to those requests and provide the data or services. The OS(opperating system) then directs the incoming traffic to the correct application based on this port number.

eg. a user accesses a website: the user’s browser initiates a connection to the server's IP address on port 80(which is designated for HTTP). The server, listening on this port, responds to the request. If the user needs to access a secure site, the browser instead connects to port 443, the standard for HTTPS.

Well-Known Ports

These ports are numbers 0 to 1023 and are reserved for common and universally recognized services and protocols. They are standerdized and managed by the IANA(Internet Assigned Numbers Authority). HTTP, for example, is used for data communication for the the WWW and uses port 80. Browsers do not tend to display the port number in order to simplyify the user exerience. And HTTPS, S standing for Secure, uses port 443. FTP, used for file transfers, uses ports 20 and 21.

Registered Ports

These ports go from 1024 to 49151 and, while they are not as strictly regulated as well-known ports, they still need to be registered and assigned to specific services by the IANA. They are used for external services that users might install such as Microsoft SQL Server, which is a database service and runs of port 1433. Software companies tend to register a port for their application in order to ensure that their software consistently uses the same port no matter the system. Registration also helps in managing network traffic and preventing port conflicts across different applications.

Dynamic/Private Ports

They are also known as ephemeral ports and range form 49152 to 65535 and are majorly used by client applications to send and recive data from servers. These ports are called dynamic because they are not fixed and can be randomly selected by the client's OS as needed. They act as temporary communication sessions and get closed once the session ends. They can also be assigned to custom server applications.

Browsing Internet Example

DNS Lookup - computer resolves the domain name to an IP address (eg. 93.184.216.34 for example.com)
Data Encapsulation

Browser generates an HTTP request.
Request is encapsulated with TCP, specifying the destination port 80 or 443.
Packet includes the destination IP address (eg. 93.184.216.34.)
On the local network, the computer uses ARP to find the MAC address of the default gateway (router).

Data Transmission

Data frame is sent to the router's MAC address.
Router forwards the packet toward the destination IP address.
Intermediate routers continue forwarding the packet based on the IP address.

Server Processing

Server receives the packet and directs it to the application listening on port 80 or 443.
Server processes the HTTP request and sends back a response following the same path in reverse.

Response Transmission

Server sends the response back to the client’s temporary port, which was randomly selected by the client’s operating system at the start of the session.
Response follows the reverse path back through the network, being directed from router to router based on the source IP address and port information until it reaches the client.

Anddd...thats all

Useful video I found to learn about ports - https://www.youtube.com/watch?v=h5vq9hFROEA

Network Components

Palak Hirave — Mon, 20 Apr 2026 13:42:44 +0000

Devices are able to communicate with each other, share resources, and access the internet with almost uniform consistency but, what exactly enables this? Various network components work together to make this happen.

End Devices

End Devices, also known as hosts, are devices that end up receiving or sending data within a network(e.g. phones, laptops). Users interact with these devices directly to perform tasks such as browsing the web, sending messages and creating documents. These devices play an important role in data generation and data consumption, like when users stream videos(consumption) or send emails(generation). End devices serve as the primary UI(User Interface) to the WWW(World Wide Web), enabling them to access network resources and services seamlessly. This can be done through both wired(Ethernet) and wireless(Wi-Fi) connections. An example of this is an office employee using a laptop to connect to the office's network to access online resources and communicate with others. The end device is the laptop and serves as the user's way to interact with the network.

Intermediary Devices

These devices assist the flow of data between end devices, within a LAN or between different networks. They include routers, switches, modems and access points, all of which play a role in ensuring efficient and secure data transmission. These devices are responsible for things such as packet forwarding, directing data packets to their destinations(by reading network address info) and determining the most efficient paths. Their main job is to connect networks and control network traffic to enhance performance and reliability. Intermediary devices often incorporate security features like firewalls to protect certain networks from unauthorized access and potential threats. They operate at different layers of the OSI model, e.g. routers at the Network Layer and switches at the Data Link Layer, and use routing tables(a digital data file in a router or network device that acts as a roadmap to store rules and determine the best path for forwarding IP packets to their destinations) and protocols to make decisions about data forwarding.

Network Interface Card (NIC)

Is a hardware component installed into a computer/other device that enables it to connect to a network. It provides the physical interface between the device and network media and handles the sending and receiving of data across a network. Each NIC has their own unique MAC address so that devices can identify each other and enable communication at the data link layer of the OSI model. They can be designed for both wired connections(Ethernet cards that connect via cables) and wireless connections(Wi-Fi adapters using radio waves). A desktop computer may use a wired NIC with an Ethernet cable whilst your smartphone uses a wireless NIC to connect to networks via Wi-Fi.

Router

A router is an intermediary device that forwards data packets between networks and directs internet traffic. They work at the Network Layer of the OSI model and read the network address info in data packets to determine their destinations. By using routing tables and routing protocols like Open Shortest Path First(OSPF) or Border Gateway Protocol(BGP) they can find the most efficient path for the data to travel across interconnected networks and the internet. They do this by examining incoming data packets and forwarding them toward their destinations based on IP addresses. By connecting multiple networks, routers enable devices on different networks to communicate. They also manage network traffic by selecting optimal paths for data transmission, which helps prevent congestion, a process known as traffic management. Routers also enhance security by incorporating features like firewalls and access control lists, protecting the network from unauthorized access and potential threats. To understand this better, visualize all the devices in a home network(printer, smartphones, laptops, smart TV, etc.). A router connects all these devices together in a network. It also connects this network to the internet which is provided by your Internet Service Provider(ISP). The router then directs incoming and outgoing internet traffic efficiently, ensuring that each device in the network can communicate with external networks(e.g. Internet) and with each other.

Switches & Hubs

A switch connects multiple devices within the same network, usually a LAN. Don't confuse this with a router as routers can also connect various networks together(e.g. home network and the Internet). A switch only connects the devices in a single network. They operate at the Data Link Layer and use MAC addresses to forward data only to its intended recipient. They reduce network congestion and improve overall performance by managing data traffic between the connected devices. They enable devices like computers, printers, and servers to communicate directly with each other within the network. For example, in a school, switches can connect the teacher's laptops in order for them to communicate quickly and effectively with each other and share files.

On the other hand, a hub is a far more basic networking device and isn't really used anymore. You would only find a few networks still using it. It connects multiple devices in a network segment just like a router but rather than sending data to only its intended recipient it broadcasts the data to all connected ports, regardless of the destination. This means that there's increased network traffic and higher chance of data collisions(when packets of data collide, causing that bit of data to be lost and you will have to resend the file/request). It is also quite easier to hack and gather all data as every bit of it is broadcasted to all devices, even if the device doesn't open it.

Network Media and Software Components

Network Media provides the physical paths that connect devices and allow data to be transmitted between them and includes wired media such as Ethernet cables and fiber-optic cables and wireless media such as Wi-Fi and Bluetooth.

Software components define the rules and procedures for data transmission, ensuring that the info is correctly formatted, addressed, transmitted, routed and received. It does this through management software which allows administrators to monitor network performance, configure devices, and enhance security and network protocols such as TCP/IP, and HTTP to enable devices to communicate over the network.

Cabling and Connectors

These are the physical materials that are used to link devices in networks which form pathways so that data can be transmitted through them. This includes all sorts of cables such as Ethernet, Fiber-Optic(which sends data via. light pulses) and also uses connections like the RJ-45 plug which is used to directly connect network devices such as computers, switches, printers and routers. The quality and type of cabling and connectors can affect network performance, reliability, and speed. For example, in an office, Ethernet cables with RJ-45 connectors might connect desktop computers to network switches to enable high-speed data transfer across the local area network.

Network Protocols

They are a set of rules and conventions that control how data is formatted, transmitted, received and interpreted across a network. This ensures that devices from different manufacturers and with varying configurations can adhere to the same standard and communicate effectively and without errors. They encompass a large range of things such as data segmentation, addressing, routing, error checking and synchronization. Some common protocols are TCP/IP, HTTPS, SMTP, FTP and more.

Network Management Software

This consists of various tools and applications that are used to monitor, control and maintain network components and operations. These software can do things such as performance monitoring, configuration management, fault analysis and security management.

They help network admins ensure that the network remains secure, can quickly address any issues that arise and operate efficiently. For example, in a business, the IT department might use network management software to oversee all devices connected to the company network, monitor traffic for unusual activity, update device configurations remotely and enforce security policies to maintain optimal network performance and security. This can also help prevent hackers and data breaches.

Software Firewalls

This is a security application that is installed on someone's device that monitors and controls incoming and outgoing network traffic based on predetermined security rules(you can edit/change/add/modify these rules) Hardware firewalls are physical components that protect entire networks whilst software firewalls(also known as Host-based firewalls) provide protection only to the device that it has been installed on. They guard the device from threats that may have bypassed the network's physical firewall. Software firewalls help prevent unauthorized access, reject incoming packets that contain suspicious or malicious data and can be configured to restrict access to certain applications or services. For example, most operating systems include a built-in software firewall that can be set up to block incoming connections from untrusted sources. This ensures that only legitimate network traffic reaches the device and reduces the change of a virus being installed on the device.

Servers

They are powerful computers that are made to provide services to other computers(clients) over a network. They host services that the clients access, suppose opening a web page or email service. They enable resource sharing by allowing multiple users to access resources like files and printers via the network. They also handle data management by storing and managing data centrally, which simplifies backup processes and enhances security management. Rather than having hard drives all around your house where they might easily get lost or stolen, servers provide a secure place to store your data without having to worry about the physical aspects of it. Additionally, they manage authentication by controlling user access and permissions across multiple components in the network. Servers often run specialized operating systems optimized for handling multiple, simultaneous requests in what is known as the Client-Server Model(which is when the sever waits for the client to respond and then goes about it accordingly). When you browse, your browser sends a request to the server hosting that site, who then responds back with the web page data after processing the request. This is also show in the TCP 3-Way Handshake(which I will not be explaining but it's good to look into it).

Anyways...that's all for this one. Bye!

Network Concepts

Palak Hirave — Fri, 17 Apr 2026 08:41:07 +0000

Just a few key concepts to show how networking fits into the bigger picture of technology.

OSI Model

The OSI(Open Systems Interconnection) Model is a conceptual framework that standardises the functions of a telecommunication or computing system into seven abstract layers.

Layer 1 (Physical Layer)
It is the first layer in the OSI model and is the bottom most layer(it helps to imagine a pyramid and this layer being at the bottom of it). It is responsible for transmitting raw bitstreams over a physical medium. It deals with the physical connection between devices and uses hardware such as Ethernet Cables, hubs and repeaters.

Layer 2 (Data Link Layer)
This layer provides node-to-node data transfer, a direct link between two physically connected nodes. It ensures that the data frames are sent with proper synchronization, error detection and correction. Switches and bridges operate at this layer and use MAC addresses to identify network devices.

Layer 3 (Network Layer)
This layer concerns with package forwarding and figuring out the best route for packages to travel by using routers to reach the destination network. It's responsible for logical addressing and path determination to ensure that the data reaches the correct destination. Routers work at this layer and use IP addresses to identify devices and determine the most effective path for data transmission.

Layer 4 (Transportation Layer)
Provides end-to-end communication services for applications. It handles the responsibility of the reliable/unreliable delivery of data, segmentation, reassembly of messages, flow control and error checking. Protocols such as TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) function at this layer. TCP offers reliable, connection-oriented transmission with error recovery, while UDP provides faster, connectionless communication without guaranteed delivery.

Layer 5 (Session Layer)
This layer concerns itself with handling the sessions between applications. It establishes, maintains, and terminates connections, allowing devices to hold ongoing communications known as sessions. This layer is important for session checkpointing (inserting synchronization points into network data streams to allow recovery from failures without restarting the session) and recovery, ensuring that data transfer can resume seamlessly after interruptions. Protocols and APIs (Application Programming Interfaces) operate at this layer and coordinate communication between systems and applications.

Layer 6 (Presentation Layer)
This layer acts as the translator between the network format and the application layer (Layer 7). It handles data representation to ensure that the data sent by the application layer of one system is readable by the other's application layer. It does this through things such as data encryption and decryption, converting data formats and data compression. Encryption protocols and data compression techniques operate at this layer to secure and optimize data transmission.

Layer 7 (Application Layer)
This is the topmost layer and provides network services directly to end-user applications. It concerns itself with resource sharing, remote file access, and other network services. Common protocols operating at this layer include HTTP (Hypertext Transfer Protocol), FTP (File Transfer Protocol), SMTP (Simple Mail Transfer Protocol), and DNS (Domain Name System) for resolving domain names to IP addresses. This layer serves as the interface between the network and the application software.

TCP/IP Model

The Transmission Control Protocol/Internet Protocol (TCP/IP) model is a abridged version of the OSI model. It is tailored for pratical implementation on the internet and other networks.

Link Layer
This is the bottommost and is ressponsible for handling the physical aspects of network hardware and media. It includes technologies such as Ethernet for wired connections and Wi-Fi for wireless connections. This layer corresponds to the Physical and Data Link Layers of the OSI model.

Internet Layer
This layer manages the logical adressing of devices and routing of packets across networks. Protocols such as IP (Internet Protocol) and ICMP (Internet Control Message Protocol) work at this layer. This layer corresponds to the Network Layer in the OSI model.

Transport Layer
At the Transport Layer, the TCP/IP model provides end-to-end communication services that are essential for the functioning of the internet. This includes the use of TCP (Transmission Control Protocol) for reliable communication and UDP (User Datagram Protocol) for faster, connectionless services. This layer ensures that data packets are delivered in a sequential and error-free manner, corresponding to the Transport Layer of the OSI model.

Application Layer
This layer contains protocols that offer specific data communication services to applications. Protocols such as HTTP (Hypertext Transfer Protocol), FTP (File Transfer Protocol), and SMTP (Simple Mail Transfer Protocol) are used at this layer and enable functionalities such as web browsing, file transfers, and email services. This layer corresponds to the top three layers of the OSI model: Session, Presentation, Application, providing interfaces and protocols necessary for data exchange between systems.

Protocols
Protocols are standardized rules that determine the formatting and processing of data to facilitate communication between devices in a network

HTTP (Hypertext Transfer Protocol) : Used for transferring web pages, allows browsers and servers to communicate in the delivery of web content. (Application Layer)
FTP (File Transfer Protocol) : Facilitates the transfer of files between systems. It provides a way for users to upload or download files to and from servers. (Application Layer)
SMTP (Simple Mail Transfer Protocol) : Handles the transmission of email and is responsible for sending messages from one server to another, ensuring they reach their intended recipients. (Application Layer)
TCP (Transmission Control Protocol) : Ensures reliable data transmission through error checking and recovery. It also establishes a connection between sender and receiver to guarantee the delivery of data in the correct order. (Transport Layer)
UDP (User Datagram Protocol) : Allows for fast, connectionless communication, which operates without error recovery and therefore makes it ideal for applications that require speed over reliability, such as streaming services. (Transport Layer)
IP (Internet Protocol) : Used for routing packets across network boundaries and handles the addressing and routing of packets to ensure they travel from the source to the destination across diverse networks. (Internet Layer)

Learning a new skill

Palak Hirave — Wed, 15 Apr 2026 13:09:40 +0000

Hi everyone, I am going to be pausing my 100 day python challenge to start learning about cyber security as that is the field that has interested me for months and I thought that I might as well start learning it and do my python challenge side-by-side as it don't really align as much with my goals as learning cyber security does. I will be posting what I learnt here in my own words for others to read and understand.

Network Basics

Palak Hirave — Tue, 14 Apr 2026 13:22:44 +0000

What is Networking?

Networks are things that are connected, to put it simply. They are all around us and come in many different forms like

Friend and social groups
Transportation links within a city
Power supply girds
Your neighborhood

and many other examples, wherever something is connected/linked to others, it's likely to be a network.

In computing, networking is all about the connection of technological devices and how they are linked together so that you can communicate and share things with others.

There are three main components in networks:

Nodes : Individual devices that are connected to the network
Links : Communication pathways that link the nodes together(wired/wireless)
Data Sharing : The main use case of the network is to enable data exchange

In a real-world example, a group of office workers talking to each other form the network, each worker is a node and then talking to each other are the links. What they are talking about is the data being shared across these links and to the various workers.

Why is it important?
Networks are significant as they enable us to do a range of things, especially now that we have the Internet. It helps us share physical and software resources, communicate with others via instant messaging, emails, and video calls, access files and databases from any connected device, and collaborate with others to work together in real-time when they are physically far apart.

Types of Networks

There are two main types of networks, Local Area Network(LAN) and Wide Area Network(WAN).

Local Area Network
They connect devices over a small area and these types of networks are controlled by one person or body. Due to not having much scale, the data transfer rate is higher and uses Ethernet cables for wired connection or Wi-Fi for wireless.

Example of an LAN 
                   ------------
                   | Internet |
                   ------------
                        |
                        |
                   ------------
                   |  Modem   |
                   ------------
                        |
                        |
                   ------------
                   |  Router  |
                   ------------
                        |
                        |
  -------------   ------------         ----------
  |Smartphone |---|   PC     | ------- | Laptop | 
  -------------   ------------         ----------
         |             |                    |
         |             |                    |
    -----------        |                    |
    | Printer | -------|                 ----------
    -----------                          | Tablet |
                                         ----------

There can be a mix of wired and wireless connections, for example, the PC and printer have a wired connection whilst the smartphone and printer have a wireless one.

Wide Area Network(WAN)
WANs cover a larger area than LANs and are typically owned by multiple people/organizations. One example is the Internet, which is also the largest WAN there is. WANs tend to span across cities, countries and/or continents. Due to their sheer size, there are slower data transfer rates than LANs as they have to cover a longer distance. They utilize fiber optics, satellite links, and leased telecommunication lines in order to get data across.

How do they work together?
Multiple LANs can connect to WANs in order to grant expanded communication and resource sharing. An example of this is when large businesses connect many LANs to a WAN in order to achieve unified connection across geographical locations.

Home Networks, which are LANs, connect to their Internet Service Provider's (ISP's) WAN in order to gain acess to Internet. In this setup, a device called a modem (modulator-demodulator) acts as a bridge between your home network and the ISP's infrastructure, converting digital signals from your router into a format suitable for transmission over various media like telephone lines, cable systems, and fiber optics.

Identifing Devices

Humans use their name and fingerprint for verification/their identity. In a similar manner, computers have an IP Adress and MAC Adress, the IP Adress is like your name, something that can change whilst the MAC Adress is like your fingerprint, something that you cannot.

Internet Protocol Adress
An IP address is a set of numbers that are divided into four octets. The value of each octet will summarise to be the IP address of the device on the network. This number is calculated through a technique known as IP addressing & subnetting. IP addresses can change from device to device but cannot be active simultaneously more than once within the same network.

IP Addresses follow a set of standards known as protocols. These protocols are the backbone of networking and force many devices to communicate in the same language. Devices can be on both a private and public network. Depending on where they are will determine wether they have a public or private IP address.

A public address is used to identify the device on the Internet, whereas a private address is used to identify a device amongst other devices(eg. in a LAN).

Octet          1   2  3 4 
IP Adress     192.168.1.1

The number in each octet is between 0 and 255. 

Examples of private network IP Adress - 
   192.168.1.77
   192.168.1.84
   192.168.3.93

The first two octets stay the same for most home networks whilst the last two change.

Examples of public network IP Adress - 
   86.157.52.21
   86.157.52.95

As more devices get connected, it has become harder to find an IP address that has not already been taken up. Cisco, an industry giant in the world of networking, estimated that there would be approximately 50 billion devices connected on the Internet by the end of 2021.

The mentioned version of the IP addressing scheme is known as IPv4 which uses a numbering system of 2^32 IP addresses (4.29 billion), not enough to meet demand.

So, in order to solve this, IPv6 was thought of which supports up to 2^128 of IP addresses (340 trillion-plus), resolving the issues faced with IP and it also uses better and improved methodologies.

IPv6 Example - 2001:0db8:85a3:0000:0000:8a2e:0370:7334

It uses the hexadecimal system which ranges from 0-9 and A-F. It is known as a base sixteen numbering system used in computing to represent numbers. IPV6 consists of 8 octets.

Media Access Control Adress
Devices on a network will all have a physical network interface, which is a microchip board found on the device's motherboard. This network interface is assigned a unique address at the factory it was built at, called a MAC address. The MAC address is a twelve-character hexadecimal number split into two's and separated by a colon. The first six characters represent the company that made the network interface, and the last six is a unique number.

eg. a4:c3:f0:85:ac:2d

MAC addresses can be faked or "spoofed" in a process known as spoofing. This occurs when a networked device pretends to identify as another using its MAC address. When this happens, it can often break poorly implemented security designs that assume that devices talking on a network are trustworthy.

Eg. A firewall is configured to allow any communication going to and from the MAC address of the administrator. If a device were to pretend or "spoof" this MAC address, the firewall would now think that it is receiving communication from the administrator when it isn't in reality.

Day 21 of 100

Palak Hirave — Sun, 22 Mar 2026 07:08:50 +0000

Finished my snake game! It's supposed to be simple to play and yet my score never seems to go above five. What's your high score?

I also learnt about slicing lists and tuples and what is class inheritance.

main.py

from turtle import Screen
from snake import Snake
from food import Food
from scoreboard import Scoreboard
import time

screen = Screen()
screen.setup(width=600, height=600)
screen.bgcolor("black")
screen.title("My Snake Game")
screen.tracer(0)

snake = Snake()
scoreboard = Scoreboard()
food = Food()

screen.listen()
screen.onkey(snake.up, "Up")
screen.onkey(snake.down, "Down")
screen.onkey(snake.left, "Left")
screen.onkey(snake.right, "Right")

game_is_on = True
while game_is_on:
    screen.update()
    time.sleep(0.1)

    snake.move()

    if snake.head.distance(food) < 15:
        food.refresh()
        scoreboard.increase_score()
        snake.extend()

    if snake.head.xcor() > 295 or snake.head.xcor() < -295 or snake.head.ycor() > 295 or snake.head.ycor() < -295:
        scoreboard.game_over()
        game_is_on = False

    for segments in snake.segments[1:]:
        if snake.head.distance(segments) < 10:
            game_is_on = False
            scoreboard.game_over()

screen.exitonclick()

snake.py

from turtle import Turtle
STARTING_POSITIONS = [(0, 0), (-20, 0), (-40, 0)]
MOVE_DISTANCE = 20
UP = 90
DOWN = 270
LEFT = 180
RIGHT = 0


class Snake:

    def __init__(self):
        self.segments = []
        self.create_snake()
        self.head = self.segments[0]

    def create_snake(self):
        for position in STARTING_POSITIONS:
            self.add_segment(position)

    def add_segment(self, position):
        new_segment = Turtle("square")
        new_segment.color("white")
        new_segment.penup()
        new_segment.goto(position)
        self.segments.append(new_segment)

    def extend(self):
        self.add_segment((self.segments[-1].position()))

    def move(self):
        for seg_num in range(len(self.segments) - 1, 0, -1):
            new_x = self.segments[seg_num - 1].xcor()
            new_y = self.segments[seg_num - 1].ycor()
            self.segments[seg_num].goto(new_x, new_y)
        self.head.forward(MOVE_DISTANCE)

    def up(self):
        if self.head.heading() != DOWN:
            self.head.setheading(UP)

    def down(self):
        if self.head.heading() != UP:
            self.head.setheading(DOWN)

    def left(self):
        if self.head.heading() != RIGHT:
            self.head.setheading(LEFT)

    def right(self):
        if self.head.heading() != LEFT:
            self.head.setheading(RIGHT)

scoreboard.py

from turtle import Turtle, Screen

class Scoreboard(Turtle):
    def __init__(self):
        super().__init__()
        self.score = 0
        self.color("white")
        self.penup()
        self.goto(0,260)
        self.hideturtle()
        self.write(f"Score: {self.score}", align="center", font=("Courier", 20, "bold"))

    def increase_score(self):
        self.score += 1
        self.clear()
        self.write(f"Score: {self.score}", align="center", font=("Courier", 20, "bold"))

    def game_over(self):
        self.goto(0,0)
        self.write("Game Over.", align="center", font=("Courier", 20, "bold"))

food.py

from turtle import Turtle
import random

class Food(Turtle):
    def __init__(self):
        super().__init__()
        self.shape("circle")
        self.penup()
        self.shapesize(stretch_wid=0.5, stretch_len=0.5)
        self.color("red")
        self.speed("fastest")
        self.refresh()

    def refresh(self):
        random_x = random.randint(-280, 280)
        random_y = random.randint(-280, 280)
        self.goto(random_x, random_y)

What are you currently working on?

Day 20 of 100

Palak Hirave — Sat, 21 Mar 2026 06:38:19 +0000

Built a snake game! -or at least part of it...

Today I made the snake and got it to move around, next time I will be working on getting the points system working as well as making the apple.

Day 19 of 100

Palak Hirave — Thu, 19 Mar 2026 03:15:00 +0000

Today, I did more on turtle graphics and also leart about event listeners and multiple instances.

Basically, an event listener is a function that 'listens' for when you press a certain key and it then preformes an action when you do press that key and multiple instances means having multiple objects from the same class, in my case this would mean having multiple turtles at once.

First Project - Drawing

from turtle import Turtle, Screen

turtle = Turtle()
screen = Screen()
turtle.shape("turtle")
turtle.pensize(2)
screen.bgcolor("#FDFBD4")
screen.setup(width=700, height=500)
screen.title("Etch-a-Sketch")

def forwards():
    turtle.forward(10)
def backwards():
    turtle.backward(10)
def clockwise():
    turtle.left(10)
def anti_clockwise():
    turtle.right(10)
def clearscreen():
    turtle.penup()
    turtle.home()
    turtle.pendown()
    turtle.clear()

screen.onkey(forwards, "w")
screen.onkey(backwards, "s")
screen.onkey(anti_clockwise, "a")
screen.onkey(clockwise, "d")
screen.onkey(clearscreen, "c")
screen.listen()


screen.exitonclick()

Second Project - Turtle Race

from turtle import Turtle, Screen
import random as r

is_race_on = False
colors = ["red", "orange", "yellow", "green", "blue", "purple"]
positions_y = [-70, -40, -10, 20, 50, 80]
all_turtles = []

screen = Screen()
screen.setup(width=500, height=400)
screen.title("~~~~~~~~~~~~~~~~Turtle Race~~~~~~~~~~~~~~~~")
user_bet = screen.textinput("Place your bet", "Please bet on a colour: \n(red/orange/yellow/green/blue/purple)")

for index in range(0,6):
    turtle = Turtle("turtle")
    turtle.pensize(2)
    turtle.color(colors[index])
    turtle.penup()
    turtle.goto(-230,positions_y[index])
    all_turtles.append(turtle)
    turtle.pendown()

if user_bet:
    is_race_on = True

while is_race_on:

    for turtle in all_turtles:
        if turtle.xcor() > 230:
            is_race_on = False
            winner = turtle.pencolor()
            if winner == user_bet:
                print(f"You win! The winner was the {winner} turtle")
            else:
                print(f"You lose! The winner was the {winner} turtle")

    for turtle in all_turtles:
        distance = r.randint(0,15)
        turtle.forward(distance)


screen.exitonclick()

Day 17 of 100

Palak Hirave — Tue, 17 Mar 2026 02:00:00 +0000

Hi! Today, I learned to make my own classes. I did run into a few problems whilst working on today's project but luckly I managed to figure it out.

Resource for generating quizzes - https://opentdb.com/

Notes

# Creating Class
class User:
    # Creating Attribute
    def __init__(self, user_id, username):
        self.user_id = user_id
        self.username = username
        self.followers = 0
        self.following = 0

    # Creating Method
    def follow_count(self):
        self.followers += 1
        print(f"Yay! You have {self.followers} followers.")

    def follow(self, user):
        self.following +=  1
        user.followers += 1

        print(f"Yay! You are following {self.following} user(s).")
        print(f"Yay! They now have {user.followers} follower(s).")

user_1 = User("001", "Palak")
print(user_1)
user_2 = User("002", "Hirave")
print(user_2)
print(user_1, user_2)

user_3 = User("003", "Damn")
# Adding another attribute
user_3.notes = "~Yay~"
print(user_3.notes)

# Having a default value (followers are 0) to use later
user_4 = User("004", "Kevin")
print(user_4.followers)
user_4.followers += 1
print(user_4.followers)
print(user_4.follow_count())

print(user_1.follow_count())
print(user_3.follow_count())

user_4.follow(user_1)
user_4.follow(user_1)
user_4.follow(user_1)
user_4.follow(user_1)

'''PascalCase - HelloHowAreYou
snake_case - hello_how_are_you
camelCase - helloHowAreYou'''

Project

main.py

from data import question_data
from question_model import Question
from quiz_brain import QuizBrain

question_bank = []
for query in question_data:
    question = Question(query["question"], query["answer"])
    question_bank.append(question)

print(question_bank)

quiz_brain = QuizBrain(question_data)

game_on = True

print("Welcome to the quiz! Answer each question with a True or False. Good Luck!")
while game_on:
    quiz_brain.next_question()
    quiz_brain.check_answer()

    if False == quiz_brain.end_quiz():
        game_on = False

    if quiz_brain.question_number >= 12:
        print("Opps! We do not have any more questions! Good Job!")
        game_on = False

# TODO: ask the question
# TODO: checking if the answer is correct
# TODO: checking if we are at the end of the quiz
# TODO: Continue to show the next problem

quiz_brain.py

from data import question_data

class QuizBrain:

    def __init__(self, q_list):
        self.question_number = 0
        self.questions_list = q_list

    def next_question(self):
        # TODO: ask the question
        global main_q, key
        key = (question_data[self.question_number])
        main_q = key["question"]
        self.question_number += 1

    def check_answer(self):
        # TODO: checking if the answer is correct
        global index
        user_input = str(input(f"{main_q} - True or False: "))
        correct_ans = key["answer"]
        index = 101
        if user_input == correct_ans:
            print("Correct!")
            index = 1

        else:
            print("Wrong!")
            index = 0

    def end_quiz(self):
        # TODO: checking if we are at the end of the quiz
        global game_on
        if index == 0:
            print(f"Game ending. Final score: {self.question_number - 1}")
            game_on = False
            return game_on

        else:
            if index == 1:
                game_on = True
                print(f"Your current score is: {self.question_number}")
                print("Moving on to the next question.")
                return game_on

question_model.py

class Question:
    def __init__(self, question, answer):
        self.question = question
        self.answer = answer

data.py

question_data = [
    {"question": "A slug's blood is green.", "answer": "True"},
    {"question": "The loudest animal is the African Elephant.", "answer": "False"},
    {"question": "Approximately one quarter of human bones are in the feet.", "answer": "True"},
    {"question": "The total surface area of a human lungs is the size of a football pitch.", "answer": "True"},
    {"question": "In West Virginia, USA, if you accidentally hit an animal with your car, you are free to take it home to eat.", "answer": "True"},
    {"question": "In London, UK, if you happen to die in the House of Parliament, you are entitled to a state funeral.", "answer": "False"},
    {"question": "It is illegal to pee in the Ocean in Portugal.", "answer": "True"},
    {"question": "You can lead a cow down stairs but not up stairs.", "answer": "False"},
    {"question": "Google was originally called 'Backrub'.", "answer": "True"},
    {"question": "Buzz Aldrin's mother's maiden name was 'Moon'.", "answer": "True"},
    {"question": "No piece of square dry paper can be folded in half more than 7 times.", "answer": "False"},
    {"question": "A few ounces of chocolate can to kill a small dog.", "answer": "True"}
]

Day 16 of 100

Palak Hirave — Mon, 16 Mar 2026 02:00:00 +0000

Day 16 on the 16th day of the month. Wonderful.

Today, I learned the basics of OOP, what a class is, what are objects in the class, attributes and methods. I used this to play around with the turtle library and also downloaded prettytable from pypi.org to play around with.

I have gotten a pretty basic understanding of how classes work in general and how to use the attributes within. At first, I was a bit confused between attributes and methods but I am assuming that attributes is the variable you call on eg. class.variable and method is the fuction eg. class.do_this()

As per my understanding it is:
Class > Object > Attributes(variables)/components is has & Methods(Functions)/things that it can do

Anyways, tomorrow I will go a bit more in-depth or just continue to practice this.