What is AWS Shield?


AWS Web Application Firewall
AWS Shield
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4h 44m

This course looks at the key Security services within AWS relevant to the SysOps Administrator - Associate exam. The core to security is Identity & Access Management, commonly referred to as IAM. This service manages identities and their permissions that are able to access your AWS resources and so understanding how this service works and what you can do with it will help you to maintain a secure AWS environment.  In addition to IAM, this course covers a range of other security services covering encryption and access control

Learning Objectives

  • Learn about identity and access management on AWS including users, groups & roles, IAM policies, MFA, and cross-account access
  • Learn the fundamentals of AWS Web Application Firewall (WAF) including what it is, when to use it, how it works, and why use it
  • Learn how to manage data protection through encryption services such as the Key Management Service (KMS) and CloudHSM
  • Learn how to secure your AWS accounts using AWS Organizations
  • Understand how to configure and monitor AWS WAF, Firewall Manager, and Shield
  • Learn the fundamentals of access control via federation using AWS Cognito and AWS SSO

Hello and welcome to this section of the course focusing on the third and final service, AWS Shield. AWS Shield is closely related to both AWS WAF and also the AWS Firewall Manager. So what is it used for? Well, AWS Shield has been designed to help protect your infrastructure against distributed denial of service attacks, commonly known as DDoS. These attacks are very common, and the attack itself targets a host which might be running a website or web application, and it receives a huge number of requests simultaneously sent maliciously by an attacker from multiple distributed sources. This increase and flood of traffic aims to prevent legitimate requests getting through to host and being processed, while at the same time severely hindering the performance of the application or website. So much so in fact, that users often think the site is down. 

There are a number of different types of DDoS takes that can take place, for example, a SYN Flood. In a Syn Flood attack, a large number of connections are made to the host under attack. The host will then respond accordingly with an SYN/ACK packet, at which point the client sending the original connection request would normally respond with another SYN, completing the three-way handshake to allow communications to begin. However, this final SYN packet is not sent to the host, and this leaves a huge number of open connections on the host, resulting in diminished resources available to process legitimate requests. DNS Query Flood. By using multiple DNS queries an attacker can drain the resources against a DNS server, such as Route 53 in AWS. HTTP flood and cache-busting attacks. These attacks operate at layer seven, the application layer. And during an HTTP flood attack an attacker sends a large amount of HTTP requests, which may include POST and GET requests to a host, consuming the resources available. Cache-busting attacks are similar to HTTP floods, however, by using the HTTP request query string they are able to force content to be retrieved from the originating server, rather than from an edge location, which impacts the performance of the source servers available resources unnecessarily. AWS Shield itself is available at two different levels of features, AWS Shield Standard and AWS Shield Advanced, and AWS shield advanced has a lot more power and protection on offer than standard. AWS Shield Standard is free to everyone, well, at least anyone who has an AWS account, and it offers DDoS protection against some of the more common layer three, the network layer, and layer four, transport layer, DDoS attacks. This protection is integrated with both CloudFront and Route 53. 

AWS Shield advanced offers a greater level of protection for DDoS attacks across a wider scope of AWS services for an additional cost. This advanced level offers protection against your web applications running on EC2, CloudFront, ELB and also Route 53. In addition to these additional resource types being protected, there are enhanced levels of DDoS protection offered compared to that of Standard. And you will also have access to a 24-by-seven specialized DDoS response team at AWS, known as DRT. With these additional features, the advanced level also provides an enhanced monitoring capability allowing you to view real-time metrics of any attacks against your resources. Whereas the Standard version of Shield offered protection against layer three and layer four, Advanced also offers protection against layer seven, application, attacks. Another great advantage is the fact that you also get cost protection as a part of the plan, whereby your resources may scale suddenly and unexpectedly to cope with the rise in traffic. From a cost perspective, if your decide to go with AWS Shield Advanced then you also get AWS WAF included in the same price, and this price is currently $3,000 a month, plus data transfer fees. As you can see from this image, there are a significant amount of advantages with the Advanced version of AWS Shield over Standard. That now brings me to the end of this lecture. Coming up next I shall provide an overview of how to set up and implement AWS Shield Advanced.

About the Author
Learning Paths

Stuart has been working within the IT industry for two decades covering a huge range of topic areas and technologies, from data center and network infrastructure design, to cloud architecture and implementation.

To date, Stuart has created 150+ courses relating to Cloud reaching over 180,000 students, mostly within the AWS category and with a heavy focus on security and compliance.

Stuart is a member of the AWS Community Builders Program for his contributions towards AWS.

He is AWS certified and accredited in addition to being a published author covering topics across the AWS landscape.

In January 2016 Stuart was awarded ‘Expert of the Year Award 2015’ from Experts Exchange for his knowledge share within cloud services to the community.

Stuart enjoys writing about cloud technologies and you will find many of his articles within our blog pages.