When you’re managing stuff in the cloud, one big challenge is making sure your private things can safely connect to the internet inside your private space. That’s where Network Address Translation (NAT) comes in. People often talk about two main options: NAT Gateway and NAT Instance. In this guide, we’ll break down these choices to help you make the right decision for your cloud setup.

A] NAT Gateways: Streamlined Simplicity: – 

1] Fully Managed Solution: NAT Gateway is fully managed by AWS, which means they handle all the technical stuff, like making sure they’re always available and can handle lots of internet traffic. You don’t have to worry about it.

2] High Availability: These Gateway are spread out in different availability zone, so if something goes wrong in one zone, your internet traffic switches smoothly to another location. It’s like having a backup plan for your internet connection.

3] Adapts Automatically: NAT Gateways are pretty smart. They can grow or shrink as needed, depending on how much internet traffic you have. You don’t have to adjust them yourself; AWS takes care of it. This keeps your internet running smoothly.

4] Top-Notch Security: Security is a top priority. NAT Gateway are super secure, and you can put them in a super secure area. Your outgoing data is well protected.

5] Easy to Set Up: Setting up a NAT Gateway is as easy as making a cup of tea. You don’t need to be a tech expert. It’s beginner-friendly.

6] Predictable Basic Costs: You know exactly how much you’ll pay. There are no surprise charges. You’re charged by the hour and for the data you use. It’s easy on your budget.

7] Heavy Data Processing and Cost: Just keep in mind, if you have tons of internet traffic, it might cost more because of the high data processing. So, think about what you need carefully.

B] NAT Instances: Customizable Control :- 

NAT Instances: Your Custom Canvas

Custom Control: You’re in charge of everything – from choosing the right setup to handling software updates. f you want complete customization, this is your playground.

Customize Security : Think of security as a piece of art, and you’re the artist. You can configure your own security rules and access control to fit your exact needs. Make it as tight or flexible as you want.

Cost and Scaling: NAT Instances give you cost flexibility, but you need to manage scaling on your own. As your setup grows, costs might change depending on your Ec2 instance server size.

No Extra Data process Costs: Unlike NAT Gateways, NAT Instances don’t charge you extra for data processing. You pay for the resources you use, like the EC2 instances and data transfer, and that’s it.

Differences between NAT Gateway and NAT Instance :


NAT gateway

NAT Instance


Highly available. NAT gateways in each Availability Zone are implemented with redundancy. Create a NAT gateway in each Availability Zone to ensure zone-independent architecture.

Use a script to manage failover between instances.


Scale up to 100 Gbps.

Depends on the bandwidth of the instance type.


Managed by AWS. You do not need to perform any maintenance.

Managed by you, for example, by installing software updates or operating system patches on the instance.


Software is optimized for handling NAT traffic.

A generic AMI that’s configured to perform NAT.


Charged depending on the number of NAT gateways you use, duration of usage, and amount of data that you send through the NAT gateways.

Charged depending on the number of NAT instances that you use, duration of usage, and instance type and size.

Type and size

Uniform offering; you don’t need to decide on the type or size.

Choose a suitable instance type and size, according to your predicted workload.

Public IP addresses

Choose the Elastic IP address to associate with a public NAT gateway at creation.

Use an Elastic IP address or a public IP address with a NAT instance. You can change the public IP address at any time by associating a new Elastic IP address with the instance.

Private IP addresses

Automatically selected from the subnet’s IP address range when you create the gateway.

Assign a specific private IP address from the subnet’s IP address range when you launch the instance.

Security groups

You cannot associate security groups with NAT gateways. You can associate them with the resources behind the NAT gateway to control inbound and outbound traffic.

Associate with your NAT instance and the resources behind your NAT instance to control inbound and outbound traffic.

Network ACLs

Use a network ACL to control the traffic to and from the subnet in which your NAT gateway resides.

Use a network ACL to control the traffic to and from the subnet in which your NAT instance resides.

Flow logs

Use flow logs to capture the traffic.

Use flow logs to capture the traffic.

Port forwarding

Not supported.

Manually customize the configuration to support port forwarding.

Bastion servers

Not supported.

Use as a bastion server.

Traffic metrics

View Cloudwatch

View Cloud Watch metrics for the instance.

Timeout behavior

When a connection times out, a NAT gateway returns an RST packet to any resources behind the NAT gateway that attempt to continue the connection (it does not send a FIN packet).

When a connection times out, a NAT instance sends a FIN packet to resources behind the NAT instance to close the connection.

IP fragmentation

Supports forwarding of IP fragmented packets for the UDP protocol.

Does not support fragmentation for the TCP and ICMP protocols. Fragmented packets for these protocols will get dropped.

Supports reassembly of IP fragmented packets for the UDP, TCP, and ICMP protocols.

Choosing Your NAT Option: NAT Gateways vs. NAT Instances

Think of this decision like picking a vehicle for a road trip. Each option is like a different type of car. Let’s break it down:

A] NAT Gateways: The Reliable Sedan

1] Smooth and Steady: NAT Gateways are like a trusty sedan. They work well without much trouble.

2] Always On: They’re reliable and work 24/7, so your apps are always connected.

3] Auto-Pilot: Just like a car with cruise control, NAT Gateways adjust to traffic changes on their own.

4] Top Security: They’re safe, with strong security features to protect your data.

5] Cost Consideration: But in heavy traffic, they might cost more, like a car using extra fuel.

B] NAT Instances: The Custom Sports Car

1] Custom Ride: NAT Instance are like a sports car you can customize. You set them up the way you want.

2] Traffic Handling: They can handle changes well, like a sports car switching from cruising to racing mode.

3] Your Security: You decide the security, just like choosing the security features for your car.

4] Cost Control: You have control over costs, like having a fuel-efficient car but maintaining it yourself.

5] Learning Curve: Managing NAT Instance might require more knowledge, like becoming an experienced driver.

In a nutshell:

Think of it like buying a car. Consider the road, your needs, and your style. If you want a reliable everyday car, go for NAT Gateways. But if you like customizing and are ready to manage things, choose NAT Instance like a sports car. It’s all about what suits you best on your network journey. Just remember, NAT Gateway can cost more in heavy traffic.