Information Technology Reference
In-Depth Information
1. The Web role supports the development and execution of Web appli-
cations with Internet Information Server 7.
2. The worker role provides supporting services to the Web role, for
example, in multitier applications.
3. The VM role allows the execution of a virtual machine on Windows
Server 2008 R2. The image is stored on a virtual hard disk in the
Azure storage service. This role further provides functionality for
granting privileges and using remote desktop connections.
The usage-oriented Windows Azure pricing model is based on what is
actually used so that IT solutions can be deployed without up-front invest-
ment in hardware and software and more compute power can be added
later as required. Pricing is in line with Amazon's or Google's model
(Table 16.1).
The Microsoft Azure platform currently does not provide or support any
distributed parallel computing frameworks, such as MapReduce, Dryad,
or MPI, other than the support for implementing basic queue-based job
scheduling.
Windows Azure was announced in October 2008 followed by SQLAzure
Relational Data's announcement in March 2009. In October 2010, full IIS sup-
port was added to Windows Azure.
The general characteristics of Windows Azure are as follows:
Model : Windows Azure provides both PaaS and IaaS types of cloud
services.
Compatibility : Several Microsoft products have been integrated with
Windows Azure to help cloud consumers better use and manage
cloud services. For example, consumers can use the Microsoft SQL
Server2 to access and operate their SQL Azure database.
Deployment and interface : The Windows Azure interface includes a
management portal and powerful command-line tools. The man-
agement portal and command-line tools are easy to use, and help
cloud consumers and end users manage applications and cloud ser-
vices. In addition, several Microsoft products (e.g., Microsoft Visual
TABLE 16.1
Fees for Windows Azure Compute Resources (USD per h)
Instance Type
CPU (GHz)
Memory
Disk (GB)
I/O
Costs
Extra small
1.0
768 MB
20
Low
0.05
Small
1.6
1.75 GB
225
Moderate
0.12
Medium
2 × 1.6
3.5 GB
490
High
0.24
Large
4 × 1.6
7 GB
1000
High
0.48
Extra large
8 × 1.6
14 GB
2040
High
0.96
 
Search WWH ::




Custom Search