
AWS Certified Advanced Networking – Specialty (ANS-C01) Certification Guide
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Connectivity within a VPC is relatively straightforward and easy to configure. But often, you need to build connectivity to resources outside of that VPC. This could mean allowing public access to some web servers you’re hosting, allowing your instances to download package updates from the internet, and more. This type of connectivity can be enabled using the gateway services offered by AWS. This section will look at internet gateways, NAT gateways, and egress-only gateways.
Resources within a VPC may require connectivity to the public internet. This connectivity is achieved by deploying an internet gateway (IGW) into the VPC. IGWs are horizontally scaled and highly redundant within a VPC, meaning that they are deployed across all Availability Zones (AZs) within a particular Region. From a configuration perspective, this is true for all configured IGWs and cannot be altered. They are able to support internet connectivity...