Explanation
References:
A fault domain is a grouping of hardware and infrastructure within an availability domain. Each availability domain contains three fault domains. Fault domains provide anti-affinity: they let you distribute your instances so that the instances are not on the same physical hardware within a single availability domain.

Explanation
References: https://docs.cloud.oracle.com/iaas/Content/Compute/Concepts/computeoverview.htm

Pre-authenticated requests provide a way to let users access a bucket or an object without having their own credentials, as long as the request creator has permissions to access those objects. For example, you can create a request that lets an operations support user upload backups to a bucket without owning API keys. Or, you can create a request that lets a business partner update shared data in a bucket without owning API keys.
When you create a pre-authenticated request, a unique URL is generated. Anyone you provide this URL to can access the Object Storage resources identified in the pre-authenticated request, using standard HTTP tools like curl and wget.
Understand the following scope and constraints regarding pre-authenticated requests:
Users can't list bucket contents.
You can create an unlimited number of pre-authenticated requests.
There is no time limit to the expiration date that you can set.
You can't edit a pre-authenticated request. If you want to change user access options in response to changing requirements, you must create a new pre-authenticated request.
The target and actions for a pre-authenticated request are based on the creator's permissions. The request is not, however, bound to the creator's account login credentials. If the creator's login credentials change, a pre-authenticated request is not affected.
You cannot delete a bucket that has a pre-authenticated request associated with that bucket or with an object in that bucket.
Understand the following scope and constraints regarding public access:
Changing the type of access is bi-directional. You can change a bucket's access from public to private or from private to public.
Changing the type of access doesn't affect existing pre-authenticated requests. Existing pre-authenticated requests still work.