Storage Provisioning and Networking - Deploying and Managing a Cloud Infrastructure - page 278

■ Frequency of data access:
■ How often is a particular set of data accessed? Can it be archived?
■ What is an acceptable delivery time or latency?
■ Level of redundancy required:
■ Corporate value of the data. How important is the data to the organization?
Once an organization has determined these three factors, it can make an informed
decision for choosing a cloud storage service. Table 9.3 summarizes typical use cases and
real-world examples for the aforementioned storage technologies.

TABLE 9.3 Storage technology use cases and examples

Storage Technology Use Cases Examples

Amazon EBS High- and very high-frequency,

high-value, corporate data

LinkedIn, Expedia, Dow Jones,
Unilever, Adobe, Nokia, Netflix

Amazon S3 High-frequency data, high/

medium-value, web-scale query
access; large data chunks

Amazon's network of websites,
Dropbox, Tumblr, Pinterest,
Ubuntu One

OpenStack Swift Low-frequency data, snapshots,

archival, backup

AT&T, CERN, Deutsche Tele-
com, PayPal, Intel, NASA, Sony,
Yahoo!

Apache HDFS Batch-processing system, low

frequency, high value

Facebook, Yahoo!

Cloud Storage Gateway

As enterprises move toward cloud-based storage, new challenges emerge. Cloud storage
service providers deliver their services using either Representative State Transfer (REST)
or Simple Object Access Protocol (SOAP) application programming interfaces (APIs).
Enterprise applications are usually based on block or file data abstraction, which is far
different from what the cloud service providers are offering.
A cloud storage gateway is a network server that translates cloud storage APIs such as
REST or SOAP calls to block-based storage protocols such as Internet Small Computer System
Interface (iSCSI) and Fibre Channel or file-based interfaces such as Network File System (NFS)