Cloudware Vendor Solutions - Guide to Cloud Computing for Business and Technology Managers - page 341

The end user does not manage or control the underlying infrastructure.
Their only responsibility is for entering and managing their data based on
interactions with the software. The user interacts directly with the hosted
software via the browser. We should note that SaaS existed well before the
concept of cloud computing emerged; nevertheless, it is now an integral part
of the cloud model.
Creating and delivering software via the SaaS layer is an attractive
alternative to the more traditional desktop applications, which must be
installed on the user's machine. With SaaS, the application is deployed in the
cloud, so the work of testing, maintaining, and upgrading software is greatly
simplified since it can all occur in one place rather than being rolled out to the
desktops of potentially thousands of users. Configuration testing is reduced
in complexity due to centralization and the preset restrictions in the deploy-
ment environment. Developers can also use a simplified strategy when apply-
ing upgrades and fixes. Furthermore, composition, as discussed previously,
becomes a straightforward option as soon as the cloud services are devel-
oped. Last but not least, the providers also benefit from greater protection
to their intellectual property as the application is not deployed locally and
pirated versions of the software will be much harder to obtain and distribute.
A number of typical characteristics of SaaS are listed as follows:
• Software is available globally over the Internet either free or paid for
by subscription based on customer usage.
• Collaborative working is easily provided and generally encouraged.
• Automatic upgrades are handled by the vendor with no required
customer input.
• All users have the same version of the software.
• The software will automatically scale on demand.
• Distribution and maintenance costs are significantly reduced.
There are a huge variety of SaaS applications already available, and their
number appears to be growing at an exponential rate. A small selection of
prominent examples of SaaS is discussed later, which hopefully gives a good
illustration of the SaaS approach. We recommend that you investigate for
yourself by viewing the sites mentioned, even if only briefly.
16.3.1 Google
Services such as Gmail, Google Drive, Google Calendar, Picasa, and Google
Groups are free of charge for individual users and available for a fee for orga-
nizations. These services are running on a cloud and can be invoked from
a broad spectrum of devices, including mobile ones, such as iPhones, iPads,
and Blackberrys; laptops; and tablets. The data for these services are stored
in data centers on the cloud.