You can use the following mechanisms to control access to OBS.
IAM policies define the actions that can be performed on your cloud resources, specifying what actions are allowed or denied.
IAM policies can be used to grant access to various IAM users under the same parent account.
The process is as follows:
A bucket policy applies to the configured OBS bucket and all the objects in the bucket. An OBS bucket owner can use a bucket policy to grant permissions on buckets and objects in the buckets to IAM users or other accounts.
ACLs control read and write permissions for accounts. ACL control is not as fine-grained as bucket policies and IAM policies, so IAM policies and bucket policies are recommended instead.