What is Cloud Storage ? What is DaaS ? What is the Object ?
SNIA describing cloud storage is simply the delivery of virtualised storage on demand. Different explanations you can find 1 , 2 ,3 .
DaaS (Data Storage as a Service) very easy explanation its have ; without thinking about functional interface delivering it on demand. Functional interface means access method to data like block based (ex:iscsi) or file based (NFS,WebDAV)
The keys are here, everything should be on demand , not fixed size , expandable , virtual and should be feed by different services compression, dedup, versioning , antivirus …….
Container or bucket S3 point of view are very popular terms, both of them have same meaning, grouping, storing, organising the data. You can find out comparison of S3 Support and CDMI Support here.
CRUD is another term you have to know what is it, actually very easy Create, Retrieve , Update and Delete operations are described as a CRUD and mostly operate with HTTP protocol.
You can understand what is Cloud Storage model , what is CDMI and its used for manage storage and offer service too ! if you know S3 then you can put S3 between Container and Object Storage Client which is CDMI in picture means with CDMI commands you can also do CRUD operations instead of S3.
Storage service is capacity or pool how you think, data services is describe data requirement.
CDMI can manage the data as well as a means to store and retrieve the data.
CDMI may also be used by administrative and management applications to manage containers, domains,
security access, and monitoring/billing information, even for storage that is functionally accessible by legacy or proprietary protocols. The capabilities of the underlying storage and data services are exposed so that clients may understand the offering.
CDMI is a RESTful protocol
Object Model for CDMI
Just redefine file, directory,domain and ACLs…..
Using CDMI object model client can send a PUT via CDMI to the new container URI and create a new container with the specified name. Again client can use PUT command also for upload a file or data object to inside container and also using GET command to fetch it.
Capability of storage can be sound interesting and wonder what is it such link
describe it but some quick examples ;
Query Capability of DaaS –> Do you support snapshot ?
Query Capability of DaaS –> Do you support encryption ?
Query Capability of DaaS –> Do you support geographic placement ?
Query Capability of DaaS –> Do you support export container iscsi ?
CDMI uses many different types of metadata, including HTTP metadata, data system metadata, user metadata, and storage system metadata.
Example of storage system metadata ;
Example of data system metadata ;
Every object stored in CDMI-Compliant system need to have unique identifier like GUID.
Every cloud storage system shall allow object ID-based access to stored objects by allowing the object’s ID to be appended to the root container URI. If the data object “MyDataObject.txt” has an object ID of “00006FFD001001CCE3B2B4F602032653”, the following pair of URIs access the same data object:
I find out many article from 2010 which SNIA first CDMI kickoff happen and now see that still S3 is the best because still soo much vendor use S3 for too many their own services.
I imagine that maybe in future all our Netapp , IBM , EMC and other storages can be part of the CDMI and client with querying the capability choose what they want and go go looks like its dream for now , still block and file access continue to run with old style , cloud storage mostly used a new way instead of use FTP 🙂