Google Cloud Storage is a RESTfulonline file storageweb service for storing and accessing your data on Google's infrastructure. The service combines the performance and scalability of Google's cloud with advanced security and sharing capabilities. It is an Infrastructure as a Service (IaaS), comparable to Amazon S3 online storage service.
User activation is resourced through the API Developer Console. Google Account holders must first access the service by logging in and then agreeing to the Terms of Service, followed by enabling a billing structure. As of May 21, 2011, the console is part of Google Labs, and is free up to a usage quota.
Google Storage (GS) stores objects (originally limited to 100 GiB, currently up to 5 TiB) that are organized into buckets (as S3 does) identified within each bucket by a unique, user-assigned key. All requests are authorized using an access control list associated with each bucket and object. Bucket names and keys are chosen so that objects are addressable using HTTP URLs:
Consistency - Upload operations to Google Storage are atomic, providing strong read-after-write consistency for all upload operations.
Access Control - Google Storage uses access control list (ACLs) to manage object and bucket access. An ACL consists of one or more entries, each granting a specific permission to a scope. Permissions define what someone can do with an object or bucket (for example, READ or WRITE). Scopes define who the permission applies to. For example, a specific user or a group of users (such as Google account email addresses, Google Apps domain, public access, etc.)
Resumable Uploads - Google Storage provides a resumable data transfer feature that allows to resume upload operations after a communication failure has interrupted the flow of data.