Unified Process vs Scrum
Unified Process (UP) and Scrum are two popular approaches used in software development. Both aim to improve software development efficiency and quality by promoting agile practices. However, there are some big differences between the two approaches that are worth exploring.
I’m going to provide an overview of both UP and Scrum, highlight their key differences, and discuss the differences of each system. So by the end you should have a good understanding of which approach is best suited for your software development needs.
What is Unified Process?
The Unified Process is a software development methodology that is focused on creating high-quality software through a disciplined approach to the entire life-cycle. The UP process allegedly has an “iterative and incremental” development model, where each project is broken down into four phases: inception, elaboration, construction, and transition.
(Is this sounding a bit Waterfall to you? It sure is to me.)
The inception phase focuses on gathering requirements and creating a project vision. The elaboration phase focuses on refining requirements, creating a system architecture, and developing a project plan. The construction phase involves coding, testing, and integrating the system. The transition phase involves deploying the system and transitioning it to its users.
If you’re thinking that this sounds a bit like Waterfall, you’re not entirely wrong. These blocks in the Unified Process are basically Waterfall-like phases. This is different to Scrum, where sprints aren’t supposed to have in-built phases.
The UP framework is also known for its emphasis on producing detailed documentation throughout the development life cycle. This is intended to ensure that stakeholders have a clear understanding of the project’s status, risks, and requirements at all times.
This might also be ringing some alarm bells amongst the agile crowd. You might remember “working software over comprehensive documentation” as one of the Agile Manifesto principles. I certainly do. Well, Unified Process seems to have glossed over that bit.
What is Scrum?
I’ve talked about Scrum a lot on this blog. But if you’re new here, I’ll do a quick overview.
Scrum is an agile framework for building products under conditions of uncertainty. It is based on the principles of transparency, inspection, and adaptation (which form Empiricism). Scrum breaks work into time-boxed iterations called sprints, lasting “one month or less”.(These are usually two weeks, but not always). Each sprint aims to produce at least one potentially shippable increment.
Scrum emphasizes collaboration, continuous improvement, and flexibility. The framework is designed to allow teams to quickly respond to changing requirements, and to deliver value to stakeholders early and often.
Remember, you should be creating an increment at least once a sprint. Not once after 12 “development sprints” and six “testing sprints”.
Scrum teams consist of a product owner, a scrum master, and some developers. Note that these are product developers, not software developers.
The product owner is accountable for defining the product’s vision and prioritizing the Product Backlog. The scrum master is responsible for facilitating the scrum process, coaching the team and organization on Scrum, and helping to remove impediments. The development team is responsible for delivering the product increments during the sprint.
Key Differences
While both UP and Scrum share some similarities, there are some big differences between the two approaches.
Documentation
As mentioned earlier, UP places a strong emphasis on producing detailed documentation throughout the development life cycle. This can be an advantage in projects where there is a need for extensive documentation, such as those in highly regulated industries.
In contrast, Scrum teams usually value working software over documentation. While documentation is still produced in Scrum projects, it is kept to a minimum and only produced when necessary. The Scrum Guide doesn’t give specific advice on how much to create. The team is empowered to create their own Definition of Done, of course. Which will define how much documentation the team needs to make.
Iterative Process
Both UP and Scrum are iterative methodologies, but their approach is different. UP’s iterations are sequential and are broken down into distinct phases. Each phase must be completed before moving on to the next.
Scrum’s iterations, on the other hand, are time-boxed and are usually one to three weeks. Each sprint is focused on delivering a potentially shippable product increment.
The development team continuously reviews and adapts their work throughout the sprint to ensure they are meeting the sprint goal and working to agreed levels of quality.
Roles and Responsibilities
UP and Scrum have different roles and responsibilities. In UP, there is a clear distinction between the roles of the development team and the project management team. The project management team is responsible for creating the project plan and ensuring that the project is delivered on time and within budget. The development team is responsible for actually building the product.
In Scrum, the team is self-organizing and cross-functional. The product owner is responsible for prioritizing the product backlog and ensuring that the team is working on the highest value items.
There is no “project management” team, or even project manager, in the Scrum framework. Of course, those people might exist in the firm already. But Scrum doesn’t say anything about who they are or what they do.
Scrum has a Scrum Master, but they are not a project manager. They are a servant leader.
The scrum master is responsible for facilitating the scrum process, coaching the team, and helping to remove any impediments that may arise. The developers are responsible for delivering the product increment at the end of each sprint.
The Scrum Guide used to talk about a sub-team within the Scrum team, the “developoment team”. But they got rid of that a few versions ago. Since it was confusing and unnecessary.
Change Management
Both UP and Scrum acknowledge that change is inevitable in software development. However, they approach change management differently. In UP, changes are managed through a formal change control process. Changes must be approved by the project management team before they can be implemented.
In Scrum, change is embraced and managed through the sprint backlog and product backlog.
The product owner can add, remove, or reprioritize items in the product backlog at any time. The development team is responsible for adapting to these changes and ensuring that the product increment is delivered at the end of the sprint.
The development team also manages the sprint backlog. (The Product Owner can’t really touch this). They update the sprint backlog as they create increments, learn new things, discover issues or risks, etc.
Advantages of UP
One advantage of UP is that it provides a structured approach to software development. The methodology is well-suited for large, complex projects where extensive documentation is required. UP is also flexible and can be adapted to fit a variety of project types and sizes.
Another advantage of UP is that it places a strong emphasis on project planning and risk management. This can help to minimize project risks and ensure that projects are delivered on time and within budget.
Advantages of Scrum
One of the advantages of Scrum is that it promotes collaboration and self-organization. This can lead to better team morale and higher levels of engagement. The framework is also designed to deliver value early and often, which can help to build trust with stakeholders and reduce the risk of project failure.
You are not likely to see any release to users or customers for a long time on a UP project. Again, this might feel Waterfall to you. And it probably should.
Scrum is also highly adaptable and can be used in a wide range of fields. In fact, it is intended to be used even outside of software. Some people have used Scrum to build buildings, make movies, start businesses, etc.
The methodology is particularly well-suited for contexts where there is a high degree of uncertainty and change.
Conclusion
You might have noticed that UP is a bit of a wolf in sheep’s clothing. It claims to be iterative and incremental, but it is mainly window dressing. UP is all the hallmarks of waterfall development.
Now, waterfall isn’t inherently “evil”. You just have to be aware of what it is, and what it entails. You can’t be expecting to get a release of working software a few weeks after starting a Unified Process project. (You should with Scrum, and if you don’t get one, you’re probably not doing Scrum, or not doing it well).
UP is well-suited for large, complex projects where extensive documentation is required. Scrum is ibetter suited for contexts where there is a high degree of uncertainty and change. And where you want to release something quickly and learn from it. And build your backlog dynamically, based on feedback.
Hopefully you have a better idea of the difference between Unified Process vs Scrum. They are very different approaches. Scrum is clearly inspired by the ideals of the agile software development movement. And its manifesto. Unified Process clearly isn’t.
So if Waterfall is more your thing, then you could do UP. But I don’t know why you wouldn’t do a proper waterfall approach. Like PMI / PMP or Prince2 or whatever. Let’s be honest, it’s a wolf in sheep’s clothing.
