Information Technology Reference
In-Depth Information
12.2 Overview of the Virtual Hosting Environment
The VHE is an advanced Information and Communication Technologies (ICT) envi-
ronment where business services can be integrated with one another across organi-
sational boundaries and domains. The VHE also provides the means to virtualize
the environment where the business services operate. As such, the VHE enables
new Software-as-a-Service models that exploit economies of scale for the busi-
ness service and infrastructure providers; and reduce time-to-market margins by
enabling fast service composition and business flexibility.
The virtualisation of hosting environments refers to the federation of a set of
distributed hosting environments for execution of an application and the possibility
to provide a single access point (e.g. a Gateway) to this set of federated hosting
environments.
In the following paragraphs, we will describe the solution developed in this
Business Experiment and how it applies to the online gaming scenario.
12.2.1 The Virtual Hosting Environment: Architecture & Implementation
The approach taken in the VHE is that put forward by the Service Oriented
Architecture (SOA) paradigm. From an implementation's perspective, this means
the experiment has referred to the Web Service Framework roadmap (IBM 2009a)
which is currently supported by several commercial SOA platforms and implements
service interface specifications and protocols in the WS-* stack that are being stand-
ardised mainly in OASIS and W3C.
The core implementation is therefore based on the convergence of Grid and Web
Services technology and complies with implementations of the WS-* and WSRF/
WSDM protocol stack as well as associated mission-specific standards such as
SAML and XACML.
12.2.1.1 Key Concepts
There are four key concepts in the virtual hosting environment (Brossard and Prieto
MartÃnez 2009). These concepts are:
1. The hosting environments
2. The Business-to-Business (B2B) gateways
3. The value-adding infrastructure services (e.g. security and SLA services), and
4. The VO management service
The hosting environment typically represents the physical infrastructure where
the applications (for instance the games) are being deployed, instantiated, and
executed. It should be possible to manage the hosting environments closely, and
monitor the use of resources in order to extract QoS information. Generally,
hosting environments can include servers, application gateways, data stores, etc.
The instantiation of an application refers to the creation of a unique segregated
instance with (possibly) allocated separate resources (CPU, storage) and separate
