Networking Basics

Introduction

Table of Contents

  1. What is Networking?
  2. IP Addressing
  3. Subnetting
  4. Routing
  5. Network Protocols
  6. Firewalls and Security
  7. DNS and Load Balancing
  8. Conclusion

What is Networking?

Networking is the practice of connecting computers and other devices to share resources and communicate. It involves the design, implementation, and management of network infrastructure.

Key Concepts

  • Network: A collection of interconnected devices that can communicate with each other.
  • Network Interface: A hardware or software interface that allows devices to connect to a network.

IP Addressing

IP addressing is a fundamental concept in networking, used to uniquely identify devices on a network.

IPv4 and IPv6

  • IPv4: Uses 32-bit addresses (e.g., 192.168.1.1).
  • IPv6: Uses 128-bit addresses to accommodate a larger number of devices (e.g., 2001:db8::1).

Address Classes

  • Class A: 1.0.0.0 to 126.0.0.0
  • Class B: 128.0.0.0 to 191.255.0.0
  • Class C: 192.0.0.0 to 223.255.255.0

Subnetting

Subnetting involves dividing a network into smaller, manageable segments.

Benefits

  • Improved Performance: Reduces network congestion.
  • Enhanced Security: Limits broadcast domains.

Subnet Mask

A subnet mask determines the network and host portions of an IP address (e.g., 255.255.255.0).

  • 255 represents to network part and 0 represents to host part.

Routing

Routing is the process of directing data packets from one network to another.

Static vs. Dynamic Routing

  • Static Routing: Manually configured routes.
  • Dynamic Routing: Routes are automatically learned and adjusted (e.g., using protocols like OSPF or BGP).

Routing Tables

A routing table contains rules used to determine the path for network traffic.

Network Protocols

Network protocols define the rules and conventions for communication between network devices.

Common Protocols

  • TCP (Transmission Control Protocol): Ensures reliable data transfer.
  • UDP (User Datagram Protocol): Provides faster, connectionless communication.
  • HTTP/HTTPS (Hypertext Transfer Protocol/Secure): Used for web traffic.
  • FTP (File Transfer Protocol): Used for file transfers.

Firewalls and Security

Firewalls and security measures protect networks from unauthorized access and threats.

Firewalls

  • Packet-Filtering Firewalls: Inspects packets based on rules.
  • Stateful Firewalls: Tracks active connections and makes decisions based on connection state.

Security Measures

  • Encryption: Secures data transmitted over the network.
  • Access Control Lists (ACLs): Define permissions for accessing network resources.

DNS

DNS (Domain Name System)

DNS translates human-readable domain names (e.g., www.example.com) into IP addresses.

Conclusion

Understanding these basic networking concepts will provide a solid foundation for exploring AWS networking services. In the next section, we’ll delve into how these principles apply to AWS’s cloud infrastructure and services.

Understanding AWS Networking

Introduction

We’ll explore fundamental networking concepts within AWS and how they can be used to design robust and scalable cloud architectures.

Table of Contents

  1. Overview of AWS Networking
  2. Virtual Private Cloud (VPC)
  3. Subnets
  4. Route Tables
  5. Internet Gateway
  6. NAT Gateway
  7. Security Groups
  8. Network ACLs
  9. Peering Connections
  10. Conclusion

Overview of AWS Networking

AWS networking services enable you to set up and manage your cloud network infrastructure. Key services include VPCs, subnets, route tables, and gateways. These components work together to ensure secure, scalable, and efficient network communication.

Virtual Private Cloud (VPC)

A Virtual Private Cloud (VPC) is a logically isolated section of the AWS Cloud where you can launch AWS resources in a virtual network that you define.

  • CIDR Block: The IP address range for the VPC.
  • VPC Peering: Allows you to connect multiple VPCs.
  • Default vs. Custom VPC: AWS creates a default VPC for each region, but you can create custom VPCs for more control.

Creating a VPC

  1. Go to the VPC Dashboard in the AWS Management Console.
  2. Click on “Create VPC.”
  3. Specify the CIDR block and other settings.
  4. Create and attach an internet gateway if needed.

Subnets

Subnets allow you to partition your VPC into smaller, more manageable segments.

  • Public Subnet: Accessible from the internet.
  • Private Subnet: Not directly accessible from the internet.

Creating a Subnet

  1. Navigate to the VPC Dashboard.
  2. Select “Subnets” and click “Create subnet.”
  3. Specify the VPC, CIDR block, and availability zone.

Route Tables

Route tables control the traffic routing for your VPC.

  • Main Route Table: Automatically associated with all subnets in the VPC.
  • Custom Route Tables: Can be associated with specific subnets to control routing.

Configuring a Route Table

  1. Go to the VPC Dashboard.
  2. Select “Route Tables.”
  3. Click “Create route table” and configure the routes as needed.

Internet Gateway

An Internet Gateway (IGW) allows communication between instances in your VPC and the internet.

  • Attach to VPC: An IGW must be attached to your VPC to function.

Attaching an Internet Gateway

  1. Go to the VPC Dashboard.
  2. Select “Internet Gateways” and click “Create internet gateway.”
  3. Attach the IGW to your VPC and update the route table to direct traffic to the IGW.

NAT Gateway

A NAT Gateway enables instances in a private subnet to connect to the internet without being directly exposed.

  • Elastic IP: NAT Gateways require an Elastic IP address.

Setting Up a NAT Gateway

  1. Go to the VPC Dashboard.
  2. Select “NAT Gateways” and click “Create NAT gateway.”
  3. Allocate an Elastic IP and specify the subnet.

Security Groups

Security Groups act as virtual firewalls to control inbound and outbound traffic to AWS resources.

  • Stateful: Automatically allows return traffic for allowed inbound requests.

Configuring Security Groups

  1. Go to the EC2 Dashboard and select “Security Groups.”
  2. Click “Create security group” and configure inbound and outbound rules.

Network ACLs

Network Access Control Lists (ACLs) provide an additional layer of security at the subnet level.

  • Stateless: Rules must be specified for both inbound and outbound traffic.

Setting Up Network ACLs

  1. Go to the VPC Dashboard.
  2. Select “Network ACLs” and click “Create network ACL.”
  3. Define inbound and outbound rules and associate with a subnet.

Peering Connections

VPC Peering allows you to connect two VPCs, enabling instances in different VPCs to communicate with each other as if they are within the same network.

Creating a VPC Peering Connection

  1. Go to the VPC Dashboard.
  2. Select “Peering Connections” and click “Create Peering Connection.”
  3. Specify the VPCs and update the route tables.

Conclusion

Understanding AWS networking components is crucial for designing scalable, secure, and efficient cloud architectures.

For further reading, consult the AWS VPC Documentation.