The answers by the Rational Unified Process
What are the key answers that Rational Unified Process gives to the
problems that we face in Software Engineering.
If you look to the most serious problems encountered during a software
engineering project then the majority of them find their root in
communication problems, and the remaining problems are related
to not obeying the basic software engineering practices, such as
using a configuration management system. (CMM level 2 desribes these
Communication is not only communication between the customer
and the project team, but also between the analists, the architects,
the designers, and the implementer, and even peer communication.
Almost all project failures are caused by communication problems
on a certain level. What are the answers that RUP gives to the
problem of communication.
Process as the answer
RUP says that the answer is to define a good process. That is
not so strange, because it is already in the name. Process is
needed, but it is not the answer to the communication problem.
Communication has to do with people. When there are communication
problems, changing the process alone does not help. Usually,
"improving" the process, leads to more regulations and longer
communication lines. It leads to a further specialisation of
roles, which is likely to introduce more communication
Formalization as the answer
Another answer that RUP gives to communication problem is
to formalize the language used for the communication. The
language RUP uses is the Unified Modeling Language (UML),
which is a set of diagrams that are linked with each other.
However, formalizing a language is not the sole solution
to a communication problem. It requires people to learn a
new language and to become fluent in that language. Although
people say that a picture says more than a thousands words,
it is by no means true that diagrams are a better way to
communicate than spoken languages or working software.
The problem with diagrams is that they do not always solve
Tooling as the answer
To answer a lot of internal communication problems,
Rational provides a set of tools which support each aspect
of RUP, from use cases to test cases and from user requiments
engineering to round-trip engineering. Tools can indeed help
with maintaining consistency and tracing between the various
deliverables that a software project consists of. And tools
can also support the use of a formal specification language.
But tools also require discipline. A tool itself might
introduce more troubles than it solves. Again, it is not
obvious that tools do prevent communication problems.
The best practices
RUP talks about the six best practices, suggesting
that these are the only, or at least the most important,
six best practices. Not all of the best practices address
the communication problems.
The conclusion must be that each of these best practices have good
communication as a prerequisite. Without good communication, they
all fail to achieve their goal and act as stimulance for the
traditional waterfall way of working where real communication is
replaced by stacks of documentation that do not contribute much to
producing business value for the customers.
This manifesto states that we should value people and interactions
over processes and tools. In the last years, Agile software
development methodes have gained a lot of interest, and have
led to many succesfull projects where traditional style of
development (waterfall) have failed.
Although Robert Martin developed an agile instantiation of RUP
that is XP written upside down), I think that
RUP as a replacement of traditional style of working, will not lead
to a more agile way of working where good communication abounds
between all stakeholders of the software development process (including
the customers of course). I think it is not radical enough to break
away from all the bad practices that are found in traditional software
development projects, and I am afraid that in some cases the best practices
will actually be perverted into bad practices that prevent healthy
- Develop Iteratively:
Iterative development is only really going to work if
it is supported by intensive communication with the
customers. Because RUP divides the whole software
development process in a number of phases, the intention
to develop in short iterations can easy be reduce to the
traditional waterfall manner of working. Iterations should
be really short (weeks not months) to stimulate interaction.
- Manage Requirements: Again, managing your requirements
itself only works if you have good communication with the
customers, otherwise it will only produce thick documents,
which only will stimulate a waterfall manner of working, and
stop communication. By the way, it is far more important
to manage your risks than your requirements.
- Use component architectures: This is a tool independent
of the quality of communication.
- Model visually: Again, this is a tool. It is doubtful
whether visual models can replace working software in the
communication with the customer. Most programmers can program
without visual models. Putting extensive energy in making
visual models as part of the design phase, will easily reduce
RUP project into a traditional waterfall project. (It is okay,
if it the models are used to generate execution code.)
- Verify quality: The most used method of verifying
quality is systematic testing. The best method is
pair programming (continious peer
review). Again, communication is the central factor.
- Control changes: Without good communication between
developers the goal to control changes will result in
procedures that will hinder making changes in the latter stages
of the project. We can only embrace changes if good communication