Global Positioning System Reference
In-Depth Information
Deploying them on a PaaS or IaaS infrastructure (Baranski et al. 2010;
Schäffer et al. 2010).
Running several instances of the service transparently, especially
during peak request periods.
Deploying the services on distributed computing frameworks such as
Hadoop.
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Decomposing the service request into a workfl ow (either dynamically or
otherwise) and orchestrating the workfl ow as a composite service.
In some deployment, the SaaS developer has to take care of the task
decomposition, scheduling and execution logic, e.g., Hadoop-based
SaaS. Owonibi (2012) has demonstrated the dynamic decomposition and
orchestration of geoprocessing query requests based on computation
intensiveness of the query, data location, and different server capabilities
among a group of collaborating servers.
Platform as a Service (PaaS)
In this service model, users are provided with a computing platform for
application design, development, testing and deployment. This typically
includes the operating system, databases, and application development and
execution environment. Common examples of this service include AWS
Elastic Beanstalk,
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Oracle PaaS Platform,
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Windows Azure
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and Google
Apps Engine
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(GAE), etc. Microsoft Azure and GAE are used to describe
how this model can be coupled with on-line geoprocessing.
Typically, PaaS consists of an application server (inside which the
developed web application is deployed), a computing environment for
executed non-web-based applications, a data persistence layer, and cloud
management functionalities, and all are offered as services. Data persistence
layer in GAE consists of the App Engine Datastore (which is a schema-less
object datastore implemented on BigTable
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and Google File System
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for
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The Apache Hadoop software library is a framework that allows for the distributed processing
of large data sets across clusters of computers using simple programming models. See http://
hadoop.apache.org/, “last seen on 31 March 2013”
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AWS Elastic Beanstalk is an even easier way to quickly deploy and manage applications in
the Amazon Web Services Cloud, http://aws.amazon.com/elasticbeanstalk/, “last seen on
31 March 2013”
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http://www.oracle.com/us/solutions/cloud/platform/overview/index.html, “last seen
on 31 March 2013”
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Microsoft's solutions for application deployment in their cloud. See http://www.
windowsazure.com/en-us/, “last seen on 31 March 2013”
20
Used to deploy application in Google's cloud. https://developers.google.com/appengine/,
“last seen on 31 March 2013”
21
BigTable is a distributed storage system for managing structured data that is designed to
scale to a very large size: petabytes of data across thousands of commodity servers.
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A scalable distributed fi le system for large distributed data-intensive applications
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