Essential networking concepts for Backend Development:

Basic Network Components

1-->IP Address: Unique numerical identifier assigned to devices on a network, allowing them to communicate with other devices through the Internet Protocol (IP).

Types:

• IPv4: 32-bit address, e.g., 192.168.1.1 (most common).
• IPv6: 128-bit address, e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334(designed to replace IPv4 due to exhaustion).

2-->Port: A virtual point where network connections start and end. It's a number that tells the computer which program should receive incoming data.

Common Ports:

• 80: HTTP(Regular web traffic)
• 443: HTTPS(Secure web traffic)
• 21: FTP (File transfer)
• 22: SSH(Secure Shell)
• 3306: MySQL(Database)

3-->Domain Name: Human-readable address that corresponds to an IP address, making it easier to access websites.

Structure: Composed of subdomains and a top-level domain (TLD), e.g., www.example.com.

4-->DNS (Domain Name System):

Function: Translates domain names into IP addresses, allowing browsers to load Internet resources.

Network Protocols

1-->TCP (Transmission Control Protocol):

Features:

• Establishes a connection before data transfer.
• Ensures data integrity through error-checking and retransmission of lost packets.
• Use Cases: Web browsing, email, and file transfers where reliability is crucial.

2-->UDP (User Datagram Protocol):

Features:

• No connection establishment, leading to lower latency.
• Does not guarantee delivery or order of packets.

• Use Cases: Streaming services, online gaming, and VoIP where speed is prioritised over reliability.

3-->HTTP (HyperText Transfer Protocol):

Request Methods:

• GET: Requests data from a specified resource.
• POST: Sends data to a server to create/update a resource.
• PUT: Replaces all current representations of the target resource with the uploaded content.
• DELETE: Removes the specified resource.

Status Codes:

• 2xx: Indicates successful requests (e.g., 200 OK).
• 3xx: Indicates redirection (e.g., 301 Moved Permanently).
• 4xx: Indicates client errors (e.g., 403 Forbidden).
• 5xx: Indicates server errors (e.g., 500 Internal Server Error).

Security Concepts

1. HTTPS: Extension of HTTP that uses SSL/TLS to encrypt data exchanged between the client and server, ensuring privacy and data integrity.
2. SSL/TLS: Protocols that provide secure communication over a computer network by encrypting the data transmitted.
3. Authentication: Process of verifying the identity of a user or system, often through credentials like usernames and passwords.
4. Authorization: Process of determining what an authenticated user is allowed to do, often managed through roles and permissions.
5. CORS (Cross-Origin Resource Sharing): Security feature that allows or restricts resources requested from another domain outside the domain from which the first resource was served.