Fundamental information

Note：

The authorization granularity of cloud products is divided into three levels: service level, operation level, and resource level, based on the degree of granularity.

• Service level: It defines whether a user has the permission to access the service as a whole. A user can have either full access or no access to the service. For the authorization granularity of cloud products at service level, the authorization of specific APIs are not supported.
• Operation level: It defines whether a user has the permission to call a specific API of the service. For example, granting an account read-only access to the CVM service is an authorization at the operation level.
• Resource level: It is the finest authorization granularity which defines whether a user has the permission to access specific resources. For example, granting an account read/write access to a specific CVM instance is an authorization at the resource level.

API authorization granularity

Two authorization granularity levels of API are supported: resource level, and operation level.

• Resource level: It supports the authorization of a specific resource.
• Operation level: It does not support the authorization of a specific resource. If the policy syntax restricts a specific resource during authorization, CAM will determine that this API is not within the scope of authorization, and deem it as unauthorized.
  

Read operations