Assigning access to AWS accounts
Now that we can sign in to AWS SSO with our external IDP, we need to assign accounts to users within AWS SSO in order to close the loop between the authorization controlled by the IDP and the authorization controlled by AWS. If we considered the IDP's authorization control coarse-grained, AWS SSO provides options for fine-grained control through a variety of mechanisms. Let's start with some basic authorization controls and refine the permissions further as we go.
We can see all of our AWS accounts listed in the AWS accounts menu inside AWS SSO, as illustrated in the following screenshot:
Presently, we have no users assigned to any of them. We also do not have any permission sets assigned to any of the accounts. A permission set defines what an AWS user can do within an AWS account when signing in through AWS SSO. A permission set is stored as an AWS IAM role that is assumed...