We have our identity server implemented using identity server
https://github.com/IdentityServer/IdentityServer3 or https://github.com/IdentityServer/IdentityServer4
And user will authenticate and get the access token from the identity server. We have some APIs developed in AWS api gateway. Just wondering what is the common practice to implement the authentication / authorization in the aws api gateway. We would prefer to use the existing access token from the identity server in the API gateway.