AWS Academy Cloud Foundations - Module 5 - Part 1

Summary

This video explores key AWS networking and security features for Virtual Private Cloud (VPC) setups. It covers AWS Direct Connect for private, high-throughput connections, VPC endpoints for private access to services like S3 and DynamoDB, and AWS PrivateLink to securely connect cloud applications. It also discusses VPC peering and introduces Transit Gateway to simplify complex VPC networks. On the security side, the video explains the role of Security Groups and Network ACLs in managing traffic, highlighting their differences in scope, rule types, and statefulness. These tools are essential for building secure, scalable AWS architectures.

Takeaways

• 😀 AWS Direct Connect enables a dedicated, private connection between your network and AWS locations, improving bandwidth throughput and network consistency.
• 😀 A VPC Endpoint allows private connections between your VPC and services like Amazon S3 and DynamoDB, keeping traffic within the Amazon network.
• 😀 AWS PrivateLink ensures secure, private connectivity between VPCs, AWS services, and on-premises applications without exposing data to the public internet.
• 😀 VPC Peering is a method to connect multiple VPCs, but it can become complex when scaling to hundreds of VPCs, requiring numerous direct connections.
• 😀 The AWS Transit Gateway simplifies network architecture by acting as a central hub for connecting multiple VPCs and on-premises networks.
• 😀 Security Groups act as virtual firewalls for EC2 instances, controlling inbound and outbound traffic at the instance level. They are stateful, meaning outbound traffic is allowed by default.
• 😀 Network ACLs control inbound and outbound traffic at the subnet level. They are stateless, requiring both inbound and outbound rules to be defined.
• 😀 Security Groups support only 'allow' rules, whereas Network ACLs support both 'allow' and 'deny' rules.
• 😀 Security Groups are evaluated before making a decision to allow traffic, while Network ACLs evaluate rules in numerical order until a match is found.
• 😀 Using AWS Direct Connect, PrivateLink, VPC Endpoints, and Transit Gateway together helps streamline network connectivity and enhance security across multiple AWS services and VPCs.

Q & A

What is AWS Direct Connect, and how does it improve network performance?

AWS Direct Connect establishes a dedicated, private connection between your on-premises network and AWS. This connection increases bandwidth throughput and provides a more consistent network experience than typical internet-based connections or VPNs, ensuring lower latency and higher reliability.

How do VPC endpoints work, and what are their benefits?

VPC endpoints allow private connections between your VPC and AWS services like Amazon S3 and DynamoDB. By using VPC endpoints, traffic between your VPC and these services stays within AWS’s private network, improving security and performance as it does not traverse the public internet.

What is the difference between a VPC Gateway Endpoint and an AWS PrivateLink?

A VPC Gateway Endpoint is a private connection between your VPC and AWS services like Amazon S3 or DynamoDB. In contrast, AWS PrivateLink provides secure, private connectivity between VPCs, AWS services, and on-premises applications, with traffic staying entirely within the Amazon network and avoiding exposure to the public internet.

What is a Transit Gateway, and why is it useful for managing VPC connections?

A Transit Gateway acts as a hub that simplifies network connectivity by interconnecting multiple VPCs, on-premises networks, and other AWS services like Direct Connect and VPNs. It reduces the number of point-to-point connections needed, simplifying the network architecture and management.

What are security groups in AWS, and how do they differ from traditional firewalls?

Security groups in AWS are virtual firewalls that control inbound and outbound traffic to EC2 instances. Unlike traditional firewalls, security groups are stateful, meaning that once inbound traffic is allowed, the related outbound traffic is automatically permitted. Security groups only allow rules, and traffic is evaluated based on the instance’s configuration.

How do Network ACLs function, and what makes them different from security groups?

Network Access Control Lists (ACLs) work at the subnet level, controlling both inbound and outbound traffic. Unlike security groups, which are stateful, Network ACLs are stateless, meaning both inbound and outbound rules must be defined explicitly. They also allow both **allow** and **deny** rules, whereas security groups only allow rules.

What is the key distinction between stateful and stateless firewalls in AWS?

Stateful firewalls, like security groups, automatically allow the response to allowed inbound traffic. Stateless firewalls, like Network ACLs, require separate rules for inbound and outbound traffic, with no automatic allowance for related traffic.

Can a subnet in AWS be associated with multiple Network ACLs?

No, each subnet in AWS can only be associated with one Network ACL. However, a single Network ACL can be associated with multiple subnets.

What happens if you don't explicitly associate a subnet with a Network ACL?

If you don't explicitly associate a subnet with a Network ACL, the default Network ACL is automatically used for that subnet. The default Network ACL is wide open, allowing all inbound and outbound traffic.

How does a Transit Gateway simplify network management for multiple VPCs?

A Transit Gateway simplifies the management of multiple VPCs by acting as a centralized hub for connectivity. Instead of having multiple point-to-point VPC peering connections, all VPCs and on-premises networks can connect to the Transit Gateway, reducing the complexity of managing numerous connections and improving scalability.