Traditional Software Development Life Cycle Model
Before we jump into RAD vs SDLC, let’s learn what is SDLC and RAD. The traditional application development cycle can be broken down into six distinct stages. The process of software development begins with a phase called “requirement analysis,” which is then followed by “system specification,” “design and documentation,” “implementation,” “testing,” and “implementation and maintenance,” respectively. Due to the fact that each phase requires multiple teams of people with sigma-level expertise, the overall cost of this life cycle is extremely high. It would take longer to finish the development, and this model does not support incremental development or parallel development at different phases, so the time it would take to finish the development would be longer.
Rapid Application Development Cycle
It is similar to the iterative model in that the Software Development Life cycle is divided into five stages in the RAD model. RAD is an acronym for Rapid Application Development. Analysis of the requirements comes first in the software development life cycle, then comes the system specification, design, implementation, and finally maintenance of the product. Because there are no enormous fixed costs involved in this life cycle, there is only one team of sigma-level people involved in each phase. This results in a significantly lower cost overall because there are no huge fixed costs. When compared to the traditional model, the amount of time needed to develop the project would be cut in half, and this model allows for incremental developments as well as parallel developments during different phases.
Structuring projects in RAD vs traditional SDLC
Now that we have that out of the way, let’s think about how projects are organised within traditional SDLC as opposed to RAD. To begin, we can give the waterfall approach that we outlined earlier some more detail. Take, for instance, the scenario in which you wanted to develop a new custom CRM for a customer. Using the waterfall model, you and the other people involved would discuss everything that the system should be able to do. After these have been agreed upon, you can then move on to designing systems based on your specifications; however, once this step has been completed, you will no longer be able to change your requirements in the event that something else changes. The same pattern of development can be observed throughout each succeeding phase. RAD operates in a somewhat unconventional manner.
In most cases, the meeting will begin with a more general discussion about your vision for the product, but it won’t progress all the way to a full-fledged session of requirements gathering. After that, your developers will go off and construct a version of the tool that actually works, either in its entirety or as separate modules. After that, everybody gets back together to talk about the tools that were created, give their feedback, and decide what should be changed. This procedure can be carried out indefinitely many times up until the product is complete. Because of this, the RAD methodology is frequently referred to as an iterative approach to the development of software. To be more specific, the phases of designing systems, putting them into action, and testing them are all ongoing and repetitive.
When do companies turn to traditional SDLC vs RAD?
Therefore, under what conditions would you choose to use traditional SDLC vs RAD? The reality is that each strategy is suitable for its own particular set of use cases and objectives. This is something that is dependent on the specifics of what it is that you want to build, as well as the resources that are at your disposal.
In this situation, there are a some general guidelines that we can refer and follow as a point of reference.
These relate to:
- the project’s difficulty.
- How crucial to the mission it is.
- how many actors are involved.
Imagine, for the sake of argument, that you were intent on piloting a rocket ship to the surface of the moon. You are going to have to write some software in order to control the path that your rocket takes in real time as part of this project. This, of course, calls for some intricate mathematical calculations and a substantial amount of integration with other systems. It is also completely essential to the overall success of the project that you are working on. Because building the tool as quickly as possible isn’t the priority as much as getting everything perfect the first time, the traditional SDLC is probably the better option.
Then, let’s say that you wanted to build a single form that your employees could use to update their contact details in the various backend systems that you have. There may still be a significant need for such a tool from a business perspective, but it is highly unlikely that this will be a matter of life and death. The application itself is going to be fairly straightforward in terms of the technical aspects involved. Especially in light of the fact that rocket science is involved. Therefore, we have the financial flexibility to place a greater emphasis on speed while maintaining our commitment to providing excellent user experiences. As a result, RAD is the more compelling candidate.
Rapid Application Development (RAD) Vs Traditional Software Development Life Cycle Model (SDLC)
We have listed some of the primary distinctions between the Rapid Application Development (RAD) model vs the Traditional SDLC Model below:
1. Cost
The traditional software development life cycle (SDLC) model and the Rapid Application Development model have very different pricing structures. In the RAD model, we only need one person with the sigma level of expertise, whereas the Traditional model requires multiple people with the sigma level of expertise for each phase, which results in a higher overall cost of development than the RAD model.
2 . Time Taken
When compared to the conventional SDLC model, the RAD model typically results in a shorter amount of time spent on the development of any given software project. The reason for this is that the phases have been structured in such a way that they assist us in finishing the task as quickly as possible without becoming involved in pointless analysis or making adjustments while the task is being implemented.
3. Fixed Cost Vs Incremental Cost
In contrast, the RAD model does not include any such predetermined expenses for any of its phases, as is the case with the more conventional SDLC model. In the traditional model, we are required to set the budget for each phase, and if any of the phases are unable to meet the requirements, the project as a whole will be deemed a failure. Because RAD allows for incremental development to take place, even if one of the phases does not succeed in meeting the requirement, there will be no negative impact on any of the other phases, and you will still be able to proceed to the next phase. Therefore, even if some of the phases do not fulfil the requirements, this will not have an effect on any of the other phases.
4 . Type Of Team
In the conventional model of the software development life cycle, we are required to have multiple people with the sigma level of expertise in each phase of the life cycle. This results in a jump of amount in the cost of development. When compared to the RAD model, which only requires one person at the sigma level for each phase, Because RAD does not involve any fixed costs, as was stated earlier, there will be no damage done to any other phase even if some of the phases do not meet the requirements. To emphasise this point once more, I would like to point out that in the traditional model, we are required to determine the budget for each phase in advance, which results in a higher overall cost in comparison to RAD.
5 . Requirements
The only requirement that is involved in RAD is a one-time requirement in the form of a Business Requirements Document (BRD), and the team will make sure that they fulfil all of the requirements before moving on to the next phase. There is no fixed requirement that is involved in RAD. In the traditional model, the requirements are a document that is too detailed and is prepared separately at the end of each phase. If there are any changes in the requirements, then the entire development process needs to be restarted, which may delay the delivery of the final product. This demonstrates that the RAD model is more successful in meeting requirements than the conventional SDLC model is.
6 . Functional Vs Non-functional
These mandatory functional requirements are necessary in order to fulfil the business requirement, which ultimately leads to the successful delivery of the final product. Within the context of the RAD model, the concept of a non-functional requirement simply does not exist. Unlike the traditional SDLC model, which includes many non-functional requirements such as security requirements, availability requirements, performance requirements, and so on, the agile SDLC model only focuses on functional requirements.
7 . Multiple Release
In the conventional model of the SDLC, there is no provision for the simultaneous production of multiple releases during any given phase. In this case, the project as a whole is considered a failure because it will be impossible to successfully complete the remaining tasks of the phase if even one of the requirements is not met. In contrast, the RAD model allows for multiple releases to be made during each phase of the process. In the traditional model of the software development life cycle, each release must be inspected and verified thoroughly by every sigma level personnel before moving ahead. This takes significantly more time than the verification and inspection processes involved in RAD models.
8 . Communication
When it comes to the factors that determine whether or not a project is successful, communication is one of the most important factors. If we want to have a successful delivery of the final product, the traditional software development life cycle model requires that each sigma level personnel of the phase be communicated with in the appropriate manner. RAD models, on the other hand, have this communication taking place behind the scenes, and members of the team communicate with each other directly so that they can proceed to the next phase.
9 . Human Resource
In the traditional model, we are required to have multiple people at the sigma level for each phase. This not only leads to an increase in the cost of development, but it is also challenging to manage this kind of team. In contrast, the RAD model requires only one person at the sigma level to be present during each phase. As a result, it is much simpler to manage and maintain the team, and the associated costs are significantly lower.
10 . Risk
The traditional model of the software development life cycle includes many phases, each of which is fraught with potential dangers. For instance, if the requirement document is not completed or any of the sigma level personnel are not accounted for during the inspection of the release, this will lead to the failure of the entire project. In contrast, the RAD model does not involve any of these risks at any stage of the process. Each individual activity that constitutes a phase will be handled as its own mini-project and will be expected to be finished in its entirety.
11 . Process
In the traditional model of software development life cycle, we use the waterfall process, which has a linear and sequential nature of process, whereas in RAD models, we use multiple iterative and incremental nature of process. In other words, the waterfall process is used in the traditional model of software development life cycle.
12 . Communication Vs Documentation
Communication is the most crucial factor that contributes to the success of a project according to the conventional software development life cycle model. This is because communication involves all of the members of the team. However, the number of documents required is significantly higher in comparison to RAD models. The RAD model, on the other hand, is more effective than the traditional model due to the fact that it involves a greater number of documents while simultaneously decreasing the amount of communication.
13 . Deliverable
In a traditional model for software development, the deliverable is the software itself, which we can also refer to as the finished product. However, in RAD models, the deliverable could be any of the following:
14 . Pen & paper Vs Mock-up
In the conventional model of the software development life cycle, each and every requirement is written down using pen and paper; on the other hand, in RAD models, the vast majority of the requirement is written down using a mock-up. It helps to reduce time by providing an early view of the product, which will also help to discover bugs, refine, and validate requirements. This helps reduce time.
15 . Idea
In the conventional model of the software development life cycle, the idea is provided by the group of developers, but in RAD models, it originates with the customer.
16 . Rapid Prototyping Vs Prototype
When compared with RAD models, the traditional software development Life cycle model does not provide us with the option to create prototypes as quickly as the RAD models do. On the other hand, we can very quickly create a prototype using RAD models. It contributes to the improvement of the project planning and cuts down on the amount of time.
17 . Team
Because the number of documents involved in the Traditional model is greater than that in RAD models, the Traditional model requires a greater number of people for each phase. This results in a higher cost and makes it difficult to manage team members. In contrast, RAD models require only one or two people for each phase, making management much simpler and bringing down the overall cost of the project at the same time.
18 . Risk
There is a risk factor involved in each phase of the process in the traditional model of the software development life cycle. This model was developed many years ago. For instance, if the requirement document is not completed or any of the sigma level personnel are not included in the inspection of release, the entire project will be unsuccessful as a result of these omissions. On the other hand, there is never any danger of this kind connected to any stage of the RAD model at any point in time. Every single one of your assignments is going to be treated as if it were its very own little project, and you are going to be responsible for completing each one in its own right.
19 . Project type
According to the conventional software development life cycle model, software typically features multiple sigma levels; as a result, this model is not appropriate for use with smaller projects. In contrast, the software that comes with RAD models typically only has one or two sigma levels, making it an extremely efficient tool for handling and managing smaller projects.
20 . Team
When compared to RAD models, traditional Software development life cycle models waste the majority of their time due to the involvement of multiple documents. RAD models, on the other hand, save this time. Whereas with the RAD model, everything is very simple to manage, and the amount of time spent on it is significantly reduced.
21 . Risk
In the traditional model of the SDLC, there is a risk factor involved in each phase of the process. For example, if the requirement document is missed or any of the sigma level personnel are missed in the inspection of release, the whole project will fail as a result. In contrast, there is no such risk associated with any phase of the RAD model at any time. Every single assignment is going to be handled as if it were its own little project, and it has to be finished separately.
22 . Project type
According to the conventional software development life cycle model, software typically features multiple sigma levels; as a result, this model is not appropriate for use with smaller projects. In contrast, the software that comes with RAD models typically only has one or two sigma levels, making it an extremely efficient tool for handling and managing smaller projects.
23 . Team
When compared to RAD models, traditional Software development life cycle models waste the majority of their time due to the involvement of multiple documents. RAD models, on the other hand, save this time. Whereas with the RAD model, everything is very simple to manage, and the amount of time spent on it is significantly reduced.
24 . Risk
In the traditional model of the SDLC, there is a risk factor involved in each phase of the process. For example, if the requirement document is missed or any of the sigma level personnel are missed in the inspection of release, the whole project will fail as a result. In contrast, there is no such risk associated with any phase of the RAD model at any time. Every single assignment is going to be handled as if it were its own little project, and it has to be finished separately.
25 . Time
Comparatively speaking to RAD models, the traditional method for calculating variance requires an excessive amount of time. In contrast, one or two sigma levels are sufficient to complete the necessary amount of software in accordance with the specifications of the project.
26 . Cost
When using a traditional model for the software development life cycle, the cost will be extremely high because each phase will involve a number of different documents. On the other hand, when using RAD models, only one or two sigma levels are needed to complete an adequate amount of software in accordance with the requirements of the project.
27 . Maintenance
In the traditional approach, if there are any changes that need to be made in the software, there is a risk factor involved due to the large number of documents, and each document is affected accordingly. On the other hand, it is simple to accomplish in RAD models, and additional time can be avoided in the process.
RAD SDLC, Are They as Effective?
The Rapid Application Software Development Life Cycle, also known as RAD SDLC, is a process that speeds up software development by shortening the feedback and development loops. As a result, there is less of a communication gap between the two processes. In addition, the prototype’s primary focus during each and every iteration of the development cycle is not on delivering a finished product; rather, it is on ensuring that a particular feature or functionality is made in order for the user to test it and provide pertinent feedback on it. The term “Rapid Application Development,” or RAD, refers to a software platform that prioritizes speed and effectiveness in its development. However, due to these same characteristics, rapid application development is not suitable for long-term projects that require a significant amount of work. Rapid application development, on the other hand, is ideal for situations in which it is necessary to release a product as soon as possible without being required to worry about its completeness or polish. When you have finished developing all of the features for the product, you can then produce the final product by gathering all of the prototypes and incorporating the missing features into the final version of the product. The rapid application development methodology makes certain that the user is always kept up to date about how far along the software is, and that the developer always knows how to proceed with the user’s feedback. Both of these benefits are ensured by the rapid application development methodology.
Disadvantages of RAD
As is the case with other kinds of prototyping, the reason for the problems that arise with RAD is that systems analysts make the mistake of trying to rush the project. Imagine that two different sets of neighbours each hire a different set of carpenters to construct a storage shed for their belongings. The first carpenter subscribes to the SDLC school of thought, while the second carpenter adheres to the RAD school of thought. The first carpenter is methodical in his approach. He takes an inventory of every tool, lawn mower, and piece of patio furniture in order to determine the appropriate size for the shed. He also designs a blueprint for the shed and writes specifications for every piece of lumber and hardware. The shed is constructed by the carpenter in such a way that there is minimal waste, and the carpenter keeps detailed documentation regarding the manner in which the shed was constructed in case anyone wishes to construct another shed exactly like it, repair it, or paint it using the same color.
The second carpenter begins the project right away by estimating the size of the shed, obtaining a truckload of lumber and hardware, constructing a frame and discussing it with the property owner as adjustments are made when specific materials are not available, and making a trip to return the lumber that was not used. All of these steps take place in rapid succession. It may take less time to build the shed, but if there is no blueprint drawn, the documentation will never be created.
References
Board, Softwaretestingo Editorial. “Rapid Application Development Vs Traditional SDLC Model 2022.” SoftwareTestingo – Interview Questions, Tutorial & Test Cases Template Examples, 18 Dec. 2021, www.softwaretestingo.com/rapid-application-development-vs-traditional.
“Is RAD SDLC Killing Traditional Application Development?” Is RAD SDLC Killing Traditional Application Development?, kissflow.com/application-development/rad/rad-sdlc-slowly-replacing-traditional-sdlc. Accessed 11 Dec. 2022.
w3computing.com. “Comparing RAD to the SDLC.” Comparing RAD to the SDLC, 28 Aug. 2014, www.w3computing.com/systemsanalysis/comparing-rad-sdlc.
“Traditional SDLC Vs RAD | In-Depth Guide.” Traditional SDLC Vs RAD | In-Depth Guide, 20 Sept. 2022, budibase.com/blog/inside-it/traditional-sdlc-vs-rad.