A Beginners Guide To Legacy Systems

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A Beginners Guide To Legacy Systems

• Blog URL https//www.goodcore.co.uk/b
  log/legacy-systems/

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We all have dealt with slow systems at least once
in our lives, either at our homes, at our
universities or work. We all have gone through
the phase when our computers got stuck in the
middle of an important task or our favorite
application hung and the only option left was to
restart it. Have you ever wondered why this
happened or still happens? Well, if you did and
couldnt find your answer or are generally
interested to know, you are at the right
place! Through this article, we will try to
solve this mystery as we first explore what is
a legacy system. We will also look at its
drawbacks and discuss why they are still in use.
And lastly, we will look at some examples of
legacy technology. We assure you that this will
be an interesting read for you. So lets get
started!
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What Is A Legacy System?

A legacy system is an obsolete computer
system, programming language, software
application, process or technology that can no
longer be maintained, replaced or easily updated.
It certainly does not mean that the legacy system
is not in good working condition. Many
organisations or companies still find these
systems essential to their daily work. Though, it
depends upon the individual or the organisation
to either upgrade or replace it.
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• According to the definition of legacy systems
  mentioned above, legacy system is a very broad
  term and can be applied to many systems out
  there.  In this article, our focus will be
  limited to legacy software only.
• So, how to tell if the software is a legacy
  software or not?
• Usually, a software is considered a legacy
  software when it is older than ten years. The
  following factors contribute to determining a
  system as a legacy
• The system no longer supports the multiple
  software that an organisation or company requires
• The skills required to support the system are no
  longer available in the market or, in other
  words, have become obsolete
• The cost for maintenance of the legacy software
  is usually high as compared to that of modern
  software
• The performance becomes slower
• It cannot be extended or upgraded
• It takes longer than usual for maintenance
• It is unable to handle a large number of users
• But to our surprise, these systems despite being
  unreliable are still widely used by many
  organizations.

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Why Are Legacy Systems Still Used?

Believe it or not, many organizations and/or
businesses still use legacy technology even when
they can choose to migrate to the latest
technology. But the important question is why do
they still use it? There is this
famous saying, If it aint broke, dont fix
it. Hence, legacy systems are still used because
they get the work done.  Most of the legacy
systems are so old that no one knows on what
specifications do they work. Therefore, many
organisations either do not bother to disturb the
process or prefer not to introduce a new
technology altogether. So whenever you see
software or a system still in use despite it
being old, do not judge the organisation or the
company right away. But do think about the uses
which we have listed below
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Change Is Not Good
As we briefly discussed above, many organisations
do not prefer change. Hence, they barely switch
to new systems. Also, changing their systems
means providing training to the users, which
might cost them both time and money. Moreover,
chances are that the users might resist change.
Therefore, many organizations resort to legacy
technology as long as it serves their current
needs. For example, Windows XP was
first introduced in 2001 and was widely used by a
lot of users globally. In 2014, Microsoft ended
its support for Windows XP and launched newer
versions of it. However, Windows XP is still
used, if not widely. The main reason is that the
users cannot afford to upgrade their systems or
are not ready for change.

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Tailor-Made Software
Most of the legacy software is customized
according to the organization's needs at the time
of development. The software is developed with an
aim to function for a longer period, without
having to make major changes. Sinc
e organizations customize their software, which
eventually becomes part of legacy technology,
therefore it can provide the organization with a
competitive advantage over others. Hence, we
still see the software functioning well even
after 6-7 years. Of course, they need timely
maintenance.

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Bridging Older Technology With The Newer Ones
Legacy systems are still in use because there are
different types of software available that bridge
the gap between older technologies with the newer
ones. They do so by providing a
framework on which newer versions are developed
to continue the legacy of older technology which
might not exist but act as a precedent.

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Reliable
When we talk about change, we also implicitly
refer to the reliability aspect. For many
organizations, the durability and reliability of
software or a system are of utmost importance.
Because they have been using the software for a
while, which has now become a legacy. They are
afraid to test out a new system or software
because they are skeptical of the  new technology
not working as robustly as their old legacy
software did. With the legacy
software, they already know how to handle it and
hence there is predictability to how the software
will react in different circumstances. Most
importantly, they feel at ease when using a
well-known software or system rather than
familiarizing themselves with the new one.

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What Is An Example Of A Legacy System?
So far, we have understood what legacy technology
is, but to make it easy for you, let us explain
it through an interesting example. You must have
heard about NASAs Space Shuttle program, which
was an Earth-to-orbit spaceflight. Initiated in
1972, through Space Shuttles, NASA used to
transport cargo and crew members to the
International Space Station. The program was
based on multiple legacy software but mainly
on Flight Analysis and Design System
(FADS). NASAs Space Shuttle
Program was developed with an aim of 10 years of
operational life. Even though the program retired
in 2010, it worked on the same software during
those 10 years rather than upgrading to the newer
one.

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• According to research on the use of legacy
  systems in space exploration, legacy software can
  only be reused if an organization is capable of
  the following, which increases the reliability
  and quality of the software
• Verification
• Validation
• Testing
• Operational history
• These must be incorporated in SDLC phases such as
• Development
• Implementation
• Usage
• Maintenance
• Here are a few additional examples of legacy
  software that you might be interested to know
  about
• The traffic signals that we follow are still
  based on legacy technology.
• US Military, Britains Atomic Weapons
  Establishment and Airbus still use DEC
  manufactured PDP minicomputers which were
  developed in the 1970s.
• Banks still function on legacy technology.
  Whenever you transfer your money, the transaction
  happens through a legacy platform.

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Lets Have A Recap!

To summarize what legacy technology is, it is an
outdated technology, which does not support the
modern-day needs of the businesses or
organizations. Why do some people still depend on
these systems? Because they are accustomed to it
and hardly will ever switch to the latest
option. It is entirely up to you whether you opt
to keep using legacy technology or not. This
decision depends on your requirements. We cannot
completely rule them out since they are still
useful in many ways such as being reliable,
cost-effective, customizable and most
importantly, they get your work done! Yet, we
cannot also deny the fact that these do not meet
the modern-day requirements. Let us know what is
your take on legacy technology and this entire
debate of keeping them or not. Leave your
comments or reach out to us via email. We will be
glad to know your thoughts on this crucial debate.
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End.