A
software release life cycle is the sum of the stages of development
and maturity for a piece of computer software: ranging from its initial
development to its eventual release, and including updated versions of the
released version to help improve software or fix bugs still present in the
software.
Stages of development
The origin of the "alpha/beta"
test terminology is IBM. As long ago as the 1950s (and probably earlier),
IBM used similar terminology for their hardware development. "A" test was
the verification of a new product before public announcement. "B" test was
the verification before releasing the product to be manufactured. "C" test
was the final test before general availability of the product. As software
became a significant part of IBM's offerings, the alpha test terminology was
used to denote the pre-announcement test and beta test was used to show
product readiness for general availability. Martin Belsky, a manager on some
of IBM's earlier software projects claimed to have invented the terminology.
IBM dropped the alpha/beta terminology during the 1960s, but by then it had
received fairly wide notice. The usage of "beta test" to refer to testing
done by customers was not done in IBM. Rather, IBM used the term "field
test."
Pre-alpha
Pre-alpha refers to all activities
performed during the software project before testing. These activities can
include requirements analysis, software design, software development, and
unit testing. In typical open source development, there are several types of
pre-alpha versions. Milestone versions include specific sets of
functions and are released as soon as the functionality is complete.
Alpha
The alpha phase of the release
life cycle is the first phase to begin software testing (alpha is the first
letter of the Greek alphabet, used as the number 1). In this phase,
developers generally test the software using white box techniques.
Additional validation is then performed using black box or gray box
techniques, by another testing team. Moving to black box testing inside the
organization is known as alpha release.
Alpha software can be unstable and
could cause crashes or data loss. External availability of alpha software is
uncommon in proprietary software. However, open source software, in
particular, often have publicly available alpha versions, often distributed
as the raw source code of the software. The alpha phase usually ends with a
feature freeze, indicating that no more features will be added to the
software. At this time, the software is said to be feature complete.
Beta
Beta, named after the second
letter of the Greek alphabet, is the software development phase following
alpha. It generally begins when the software is feature complete. Software
in the beta phase will generally have many more bugs in it than completed
software, as well as speed/performance issues and may still cause crashes or
data loss. The focus of beta testing is reducing impacts to users, often
incorporating usability testing. The process of delivering a beta version to
the users is called beta release and this is typically the first time
that the software is available outside of the organization that developed
it.
The users of a beta version are
called beta testers. They are usually customers or prospective
customers of the organization that develops the software, willing to test
the software without charge, often receiving the final software free of
charge or for a reduced price. Beta version software is often useful for
demonstrations and previews within an organization and to prospective
customers. Some developers refer to this stage as a preview, prototype,
technical preview (TP), or early access.
Some software is kept in perpetual beta—where new features and functionality
are continually added to the software without establishing a firm "final"
release.
Open and closed beta
Developers release either a closed beta or an
open beta; closed beta versions are released to
a restricted group of individuals for a user test by invitation, while open
beta testers are from a larger group, or anyone interested. The testers
report any bugs that they find, and sometimes suggest additional features
they think should be available in the final version. Examples of a major
public beta test are:
·
In September 2000 a boxed version of Apple's Mac OS X Public Beta
operating system was released.
·
Microsoft's release of community technology previews (CTPs)
for Windows Vista in January 2005.
Open betas serve the dual purpose
of demonstrating a product to potential consumers, and testing among an
extremely wide user base likely to bring to light obscure errors that a much
smaller testing team might not find.
Impact of the World Wide Web
As the Internet has facilitated
rapid and inexpensive distribution of software, companies have begun to take
a looser approach to use of the word "beta". In February 2005 ZDNet
published an article about the recent phenomenon of a beta version often
staying for years and being used as if it were in production level,
disparagingly called "perpetual beta". It noted that Gmail and Google News,
for example, had been in beta for a long period of time and were not
expected to drop the beta status despite the fact that they were widely
used; however, Google News did leave beta in January 2006, followed by
Google Apps, including Gmail, in July 2009. This technique may allow a
developer to delay offering full support and responsibility for remaining
issues. In the context of Web 2.0, people even talk of perpetual betas to
signify that some software is meant to stay in beta state. Also, "beta" is
sometimes used to indicate something more like a release candidate, or as a
form of time-limited demo, or marketing technique .
Release candidate
A release candidate (RC)
is a beta version with potential to be a final product, which is ready to
release unless significant bugs emerge. In this stage of product
stabilization, all product features have been designed, coded and tested
through one or more beta cycles with no known showstopper-class bug. A
release is called code complete when the development team agrees that
no entirely new source code will be added to this release. There could still
be source code changes to fix defects, changes to documentation and data
files, and peripheral code for test cases or utilities. Beta testers, if
privately selected, will often be credited for using the release candidate
as though it were a finished product. Beta testing is conducted in a
client's or customer's location and to test the software from a user's
perspective.
Release
Release to manufacturing (RTM)
The term "release to
manufacturing", also known as "going gold", is a term used when a
software product is ready to be delivered or provided to the customer. This
build may be digitally signed, allowing the end user to verify the integrity
and authenticity of the software purchase. A copy of the RTM build known as
the "gold master" or GM is sent for mass duplication. RTM precedes general
availability (GA), when the product is released to the public.
It is typically used in certain
retail mass-production software contexts—as opposed to a specialized
software production or project in a commercial or government production and
distribution—where the software is sold as part of a bundle in a related
computer hardware sale and typically where the software and related hardware
is ultimately to be available and sold on mass/public basis at retail stores
to indicate that the software has met a defined quality level and is ready
for mass retail distribution. RTM could also mean in other contexts that the
software has been delivered or released to a client or customer for
installation or distribution to the related hardware end user computers or
machines. The term does not define the delivery mechanism or volume;
it only states that the quality is sufficient for mass distribution. The
deliverable from the engineering organization is frequently in the form of a
golden master media used for duplication or to produce the image for the
web.
General availability (GA)
General availability (GA) is the marketing stage at which all necessary commercialization
activities have been completed and a software product is available for
purchase, depending, however, on language, region, electronic vs. media
availability. Commercialization activities could include security and
compliance tests, as well as localization and world wide availability. The
time between RTM and GA can be from a week to months in some cases before a
generally available release can be declared because of the time needed to
complete all commercialization activities required by GA. At this stage, the
software has "gone live".
Release to web
Release to web (RTW) or web release is a means of software delivery that utilizes the
Internet for distribution. No physical media are produced in this type of
release mechanism by the manufacturer. Web releases are becoming more common
as Internet usage grows.
Support
During its supported lifetime,
software is sometimes subjected to service releases, or service packs,
sometimes also called "interim releases". For example, Microsoft released
three major service packs for the 32-bit editions of Windows XP and two
service packs for the 64-bit editions. Such service releases contain a
collection of updates, fixes and enhancements, delivered in the form of a
single installable package. They may also implement new features. Some
software is released with the expectation of regular support. Classes of
software that generally involve protracted support as the norm include
anti-virus suites and massively multiplayer online games. A good example of
a game that utilizes this process is Minecraft, an Indie Game developed by
Mojang, which features regular "updates" featuring new content and bug
fixes.
End-of-life
When software is no longer sold or
supported, the product is said to have reached end-of-life, to be
discontinued, retired, or obsolete, but user loyalty may continue its
existence for some time, even long after its platform is obsolete—e.g., the
Atari ST and Commodore's Amiga. |