Platform As A Service
Definition: Platform as a Service (PaaS) is one of three main forms
of cloud computing, where companies rent hardware and software from a third
party. The platform is accessed across a private network or the internet and
used to build applications rather than owning, running and developing on an
internal IT infrastructure.
PaaS in Relation to Other Cloud Computing Models
There are three main models in the
computing arena. Working up from the bottom there is infrastructure as a
service (IaaS), platform as a service (PaaS) and then software as a service (SaaS).
With IaaS companies rent pure servers with operating systems pre-loaded,
storage, network access and very little else. Organisations then load and
configure their own applications and data.
SaaS is the polar opposite. Organisations rent an application and the third
party providing it takes care of everything required to support that
application, configuring hardware and software, providing database engines, file
systems and everything else required. All the customer needs to provide are
internet capable PCs and local printing services.
PaaS sits in the middle of these two models. Essentially a company rents the
hardware, operating systems,
storage and network capacity that IaaS provides but also software servers
and applications environments. This gives customers a platform on which they can
load their data and start the developing applications they need. But being
between IaaS and SaaS means that there is a great deal of overlap at both ends
of the PaaS spectrum. There is no real agreement on what PaaS is and where these
three forms start and stop so perhaps an example is the best way to get the idea
A Working PaaS Example
Salesforce.com represents perhaps one of the most successful and clearest
examples of SaaS. Companies rent space on their customer relationship management
and log onto the website without having to download or install any software.
Everything is provided by the company and the only thing the customer
organisation has to do is load their data and configure their preferences.
But Salesforce.com also sells a PaaS offering, Force.com. By stripping away the
top layer of their CRM application and adding configuration tools Salesforce.com
offers customers the ability to build their own business applications. These
applications can access databases, use workflow concepts, have user interfaces
and be built and deployed rapidly.
Business Drivers for PaaS
As with most cloud computing applications cost is the major driver for customers
signing up to a PaaS offering rather than building (or continuing to develop)
their own business applications. Instead of maintaining an IT infrastructure
that covers the whole stack of the computing environment from hardware up to
applications, organisations can offload the cost and administration hassle of
looking after the bottom half of that stack, renting is from a PaaS provider.
The IT department therefore doesn’t have to bother themselves looking after
hardware, storage, networks, operating systems and software servers, they can
spend their time building business applications. This makes sense for a lot of
companies as this is where IT can deliver value to the business.
Portability of Assets and PaaS
It's not all plain sailing with PaaS though. Organisations considering using
PaaS as a strategic tool for developing applications need to consider the
stability of the company providing the service. A number of PaaS providers have
gone to the wall as the market matures and the economic environment makes
startup survival more difficult.
Organisations need to pay particular attention to the portability of the
applications they develop. If a provider does go to the wall, becomes unreliable
or undesirable in some way (perhaps upping prices once you are locked in) there
needs to be a clear exit path for the customer organisation.
Cost Savings With PaaS
The cost savings for PaaS, in common with other
computing models, are based on renting from a large provider which allows
customers to benefit from the economies of scale that the provider can achieve.
Cost savings are difficult to compare between different PaaS providers and with
other ways of developing applications, such as in-house development or
outsourcing to a software house. As off-shore development becomes more capable
and still remains cheap, PaaS faces considerable competition from traditional
models. And, vitally, organisations using these more traditional models own and
control their code and applications.
There are hidden costs in adopting PaaS as well. Some of these are related to
the 'what-if' scenarios of a PaaS provider going to the wall or becoming a
liability. But others are not. For example, building any strategic relationship
requires people to work at the interface between the two companies.
Eyes Wide Open
Don't be fooled by the ease of use that PaaS offerings present. This is a
strategic relationship and if it isn’t treated as such from board level down
then there is a high risk that cost savings and efficiency gains will not be as
good as expected. Analyse every aspect of how the company will work with a PaaS
provider and the output from such a project before making a decision.