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Free CCNA | NAT (Part 1) | Day 44 | CCNA 200-301 Complete Course

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Published on Nov 25, 2025 This response is partially generated with the help of AI. It may contain inaccuracies.

Table of Contents

Introduction

In this tutorial, we will explore Network Address Translation (NAT) as covered in Day 44 of the CCNA 200-301 complete course by Jeremy's IT Lab. NAT is a crucial networking concept that allows multiple devices on a private network to share a single public IP address. This guide will break down the key concepts, configurations, and commands related to NAT, making it easier for you to understand and implement in real-world scenarios.

Step 1: Understand Private IPv4 Addresses

Private IPv4 addresses are used within local networks and are not routable on the internet.
Common private IP address ranges include:
- 10.0.0.0 to 10.255.255.255
- 172.16.0.0 to 172.31.255.255
- 192.168.0.0 to 192.168.255.255
These addresses help conserve public IP addresses and provide security by keeping internal addresses hidden from external networks.

Step 2: Introduction to NAT

NAT translates private IP addresses to a public IP address, allowing devices on a private network to communicate with external networks, such as the internet.
There are different types of NAT, including:
- Static NAT: Maps a private IP to a public IP.
- Dynamic NAT: Maps private IPs to a pool of public IPs.
- PAT (Port Address Translation): Allows multiple devices to share a single IP address by using different ports.

Step 3: Configure Static NAT

Static NAT is ideal for servers that need a consistent address. Here’s how to configure it:
1. Access your router's command-line interface (CLI).
2. Enter configuration mode:
```
configure terminal
```
3. Define the static NAT mapping:
```
ip nat inside source static [Private_IP] [Public_IP]
```
4. Example:
```
ip nat inside source static 192.168.1.10 203.0.113.1
```

Step 4: Cisco NAT Terminology

Familiarize yourself with key NAT terminology:
- Inside Local: The private IP address of a device in the internal network.
- Inside Global: The public IP address that represents the inside local address to the outside world.
- Outside Local: The IP address of an external device as seen from the inside network.
- Outside Global: The actual IP address of the external device.

Step 5: Useful NAT Commands

Utilize the following commands to manage and troubleshoot NAT:
- To clear NAT translations:
```
clear ip nat translation *
```
- To display NAT statistics:
```
show ip nat statistics
```
These commands help you verify configurations and monitor NAT operations effectively.

Step 6: Review Key Concepts

Recap the main points covered in this tutorial:
- The importance of private IPv4 addresses and the purpose of NAT.
- Configuration steps for Static NAT.
- Understanding Cisco NAT terminology and using NAT commands.

Conclusion

By understanding and configuring NAT, you can effectively manage IP address utilization in networks. This tutorial covered the basics of private IPv4 addresses, the types of NAT, and how to configure Static NAT on Cisco devices. As a next step, consider practicing these configurations in a lab environment or utilizing simulation tools like Packet Tracer to reinforce your learning.

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