Network Protocols Overview

Definition: A set of rules and conventions for communication between network devices.
Types of Protocols:
- Transmission Control Protocol (TCP): Ensures reliable delivery of data packets, error-checking, and sequencing.
- User Datagram Protocol (UDP): Offers faster, connectionless communication without error-checking, suitable for streaming.
- Internet Protocol (IP): Routes packets between devices using IP addresses.
- Hypertext Transfer Protocol (HTTP): Used for transferring web pages over the internet.
- File Transfer Protocol (FTP): Facilitates file transfer between a client and a server.
- Simple Mail Transfer Protocol (SMTP): Used for sending emails.
- Post Office Protocol (POP) / Internet Message Access Protocol (IMAP): Used for retrieving emails.
Common Protocol Suites:
- TCP/IP: The foundational suite for the internet, combining TCP and IP.
- OSI Model: A conceptual framework with seven layers, each corresponding to a set of protocols.

Definition: A numerical label assigned to each device on a network to identify and locate them.
Types of IP Addresses:
- IPv4: Uses a 32-bit address format (e.g., 192.168.1.1), providing approximately 4.3 billion unique addresses.
- IPv6: Uses a 128-bit address format (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334), allowing for virtually unlimited IP addresses.
Address Classes (IPv4):
- Class A: 0.0.0.0 to 127.255.255.255 (large networks).
- Class B: 128.0.0.0 to 191.255.255.255 (medium-sized networks).
- Class C: 192.0.0.0 to 223.255.255.255 (small networks).
Private vs. Public IP Addresses:
- Public IP: Unique on the internet; assigned by an Internet Service Provider (ISP).
- Private IP: Used within local networks; not routable on the internet (e.g., 10.0.0.1, 192.168.0.1).
Subnetting: Divides a network into smaller, manageable segments, improving performance and security.
Dynamic vs. Static IP Addresses:
- Dynamic IP: Assigned by a DHCP server; can change over time.
- Static IP: Manually assigned and does not change; useful for servers and devices requiring consistent access.

A network protocol is a defined set of rules for communication between network devices.
Transmission Control Protocol (TCP): Provides reliable delivery of data through error-checking and sequencing protocols.
User Datagram Protocol (UDP): Facilitates faster, connectionless communication ideal for streaming applications; lacks error-checking.
Internet Protocol (IP): Responsible for routing packets between devices based on their IP addresses.
Hypertext Transfer Protocol (HTTP): Core method for transferring web pages across the internet.
File Transfer Protocol (FTP): Enables file transfers between clients and servers.
Simple Mail Transfer Protocol (SMTP): Protocol used for sending outbound emails.
Post Office Protocol (POP) / Internet Message Access Protocol (IMAP): Used for retrieving email messages from mail servers.
Common Protocol Suites:
- TCP/IP: Fundamental suite for internet communications, integrating TCP and IP.
- OSI Model: A framework consisting of seven layers, with each layer linked to a specific set of protocols.

An IP address is a numerical identifier for each device connected to a network, aiding in identification and location.
Types of IP Addresses:
- IPv4: Format includes 32 bits, accommodating approximately 4.3 billion unique addresses (e.g., 192.168.1.1).
- IPv6: Uses a 128-bit format, allowing for an almost limitless number of addresses (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334).
Address Classes for IPv4:
- Class A: Range from 0.0.0.0 to 127.255.255.255, suited for large networks.
- Class B: Ranges between 128.0.0.0 to 191.255.255.255, ideal for medium-sized networks.
- Class C: Ranges from 192.0.0.0 to 223.255.255.255, designed for smaller networks.
Private vs. Public IP Addresses:
- Public IP: Unique on the global internet, assigned by Internet Service Providers (ISPs).
- Private IP: Utilized within local networks; not routable on the internet (common examples include 10.0.0.1, 192.168.0.1).
Subnetting: Technique for dividing larger networks into smaller sub-networks, enhancing performance and security.
Dynamic vs. Static IP Addresses:
- Dynamic IP: Assigned by a DHCP server and may change over time.
- Static IP: Assigned manually; remains constant, beneficial for servers and devices that need stable addresses.