AWS Network ACL and subnets: network level security
Learn how to secure your VPC using an AWS Network ACL and subnets. Network ACLs act as a firewall for controlling traffic in and out of a VPC subne...Learn More
In this article, I’m going to break AWS networking down to its basic building blocks to offer some big-picture insight. By the way, you might enjoy Cloud Academy’s course on VPCs and AWS networking.
The following are what I believe the main network-oriented services on AWS:
Here’s their definition:
Amazon Virtual Private Cloud (Amazon VPC) enables you to launch Amazon Web Services (AWS) resources into a virtual network that you’ve defined. This virtual network closely resembles a traditional network that you’d operate in your own data center, with the benefits of using the scalable infrastructure of AWS.
So if you’re already familiar with networking, you are in luck: AWS networking’s use of virtual networks closely resembles a traditional network that you’d operate in your own data center. but even if you’re still a bit new to the scene, you can hopefully still pick up some important basics.
Assuming you have an AWS account you should already have a configured VPC waiting for you. If you’d like to roll your own, open your VPC dashboard an select “Start VPC Wizard” you will see these four choices:
For the time being forget about the last two – which involve connecting to an external VPN – and concentrate on numbers one and two.
In a VPC with a Single Public Subnet, your instances run in a private, isolated section of the AWS cloud with direct access to the Internet. Network Access Control Lists and Security Groups can be used to provide close control over inbound and outbound network traffic to your instances.
In a VPC with Public and Private Subnets, besides a public subnet, this configuration adds a private subnet whose instances are not addressable from the Internet. Instances in the private subnet can establish outbound connections to the Internet via the public subnet using Network Address Translation (NAT).
So subnets come in two flavors, public and private. Here’s how they work:
Some other things to know about subnets:
AWS regions are completely isolated from each other. To reduce network traffic latency, it is usually best to choose a region that’s geographically close to you or your resources. While each AWS region is isolated, there are multiple Availability Zones within a region that are connected to each other via low-latency links.
While Network Access Control Lists and Security groups both exist to control network traffic, their main difference is that ACLs act as a firewall for controlling traffic into and out of subnets, while security groups provide security at the instance level.
When you launch a VPC, by default, an Internet Gateway (IGW) will be created and attached. As you can probably guess, this serves to connect resources within a VPC to the Internet. Now, since the Internet is where all the bad guys live, make sure you’ve locked all the doors that need locking.
Hint: If you are setting up an instance, configure your security group to allow only the minimum possible amount of incoming traffic – which is probably SSH (port 22) set to allow access only from your own IP. You can open other ports as needed later on.
Route tables direct network traffic between instances inside a subnet. If you need resources within different subnets to be able to talk to each other, then you will definitely need to understand route tables.
You are probably not going to need AWS Direct Connect unless you are planning on building significant infrastructure on AWS. Nevertheless, it is an important AWS networking concept. In a nutshell, AWS Direct Connect links a local network to your AWS resources through a dedicated connection to an AWS Direct Connect physical location (generally, a third party provider) over a standard 1 gigabit or 10 gigabit Ethernet fiber-optic cable.
If you want your users to find you, you’ll need DNS routing. The AWS networking solution to that problem is Route 53, which offers highly available and scalable Domain Name System, domain name registration, and health-checking web services. It provides services, unlike other DNS providers, but with some nice extras like:
AWS Networking is not quite the same as “old world” networking, but where it’s different, it’s usually a good thing. Here’s a summary of what we discussed:
– Different Configurations for your Network
– Regions and Availability Zones
– Security Groups and NACLs
– Internet Gateways
– Route Tables
– Health checks and DNS failover
– Routing Decision Making
Learn how Aviatrix’s intelligent orchestration and control eliminates unwanted tradeoffs encountered when deploying Palo Alto Networks VM-Series Firewalls with AWS Transit Gateway.Deploying any next generation firewall in a public cloud environment is challenging, not because of the f...
Use AWS Config the Right Way for Successful ComplianceIt’s well-known that AWS Config is a powerful service for monitoring all changes across your resources. As AWS Config has constantly evolved and improved over the years, it has transformed into a true powerhouse for monitoring your...
Cloud Academy is a proud sponsor of the 2019 AWS Summits in Atlanta, London, and Chicago. We hope you plan to attend these free events that bring the cloud computing community together to connect, collaborate, and learn about AWS. These events are all about learning. You can learn how t...
The AWS cloud platform has made it easier than ever to be flexible, efficient, and cost-effective. However, monitoring your AWS infrastructure is the key to getting all of these benefits. Realizing these benefits requires that you follow AWS best practices which constantly change as AWS...
Amazon Web Services’ resource offerings are constantly changing, and staying on top of their evolution can be a challenge. Elastic Cloud Compute (EC2) instances are one of their core resource offerings, and they form the backbone of most cloud deployments. EC2 instances provide you with...
Before migrating domains to Amazon's Route53, we should first make sure we properly understand how DNS worksWhile we'll get to AWS's Route53 Domain Name System (DNS) service in the second part of this series, I thought it would be helpful to first make sure that we properly understand...
As businesses expand their footprint on AWS and utilize more services to build and deploy their applications, it becomes apparent that multiple AWS accounts are required to manage the environment and infrastructure. A multi-account strategy is beneficial for a number of reasons as ...
AWS's WaitCondition can be used with CloudFormation templates to ensure required resources are running.As you may already be aware, AWS CloudFormation is used for infrastructure automation by allowing you to write JSON templates to automatically install, configure, and bootstrap your ...
Massive migration to the public cloud is changing architecture patterns, operating principles, and governance models. That means new approaches are vital to get a handle on soaring cloud spend. Because the cloud’s short-term billing cycles call for financial discipline, you must empower...
As companies increasingly shift workloads to the public cloud, cloud computing has moved from a nice-to-have to a core competency in the enterprise. This shift requires a new set of skills to design, deploy, and manage applications in cloud computing.As the market leader and most ma...
As Head of Content at Cloud Academy I work closely with our customers and my domain leads to prioritize quarterly content plans that will achieve the best outcomes for our customers.We started 2018 with two content objectives: To show customer teams how to use Cloud Services to solv...
“Add GPU acceleration to any Amazon EC2 instance for faster inference at much lower cost (up to 75% savings)”So you’ve just kicked off the training phase of your multilayered deep neural network. The training phase is leveraging Amazon EC2 P3 instances to keep the training time to a...