No matter the technical capabilities and talents of the team, SDLC is essential for regulating each phase in the development cycle.
Perhaps the most pragmatic advantage of the SDLC is that it provides control of the development pipeline while still ensuring that the software system complies with all the estimated requirements at each and every phase.
Although the SDLC might seem like a magic sauce to an organization's project management timeline, it does not work well when there is uncertainty about the expectations and vision of the software project.
More importantly, SDLC does not enable team members to add creative inputs, as the entire life cycle is rooted in the planning phase.
Due to the SDLC’s rather rigid and regulatory structure, many companies opt for anagile software developmentapproach with incremental fulfillments and phases towards final product deployment.
However,the SDLC approach is perhaps one of the most secure methodologies, ensuring that each project requirement is rigidly fulfilled with no funny business or inconsistencies during each step from planning to product deployment.
The 6 Steps of a Secure Software Development Lifecycle
By ensuring that your organization complies with the secure software development life cycle, you will establish a sustainable model for product planning/inception and final launch.
The secure software development life cycle is progressive and systematically structured, streamlined with the following 6 steps:
Planning and requirements analysis
Architecture, design, and development outlines
Testing and results
Release and continual maintenance
1. Planning and Requirements Analysis
Preliminary planning and requirement analysis is the most fundamental stage in a secure software development life cycle.
Requirement analysis is generally performed by senior members of the team along with corresponding customer feedback and cooperation with the sales department, sourced marketing surveys, and domain experts in the industry.
Once marketing, customer feedback, and product requirements have been aggregated, the information is used to plan a basic project approach and to conduct a preliminary feasibility study.
A feasibility study estimates the short and long-term viability of the project from an economical, operational, and technical lens.
At the end of planning and requirement analysis, the team should have an outcome from their technical feasibility study to work with.
From there, they can define a variety of technical approaches to implement the project seamlessly with optimized, minimum risks.
Once senior members have fulfilled a baseline requirement and feasibility analysis, they must clearly define and document product-specific requirements and approach them with customer/market analysts.
This approval process can ultimately be executed through a software requirement specification (SRS) document, a comprehensive delineation of product requirements to be designed and developed throughout the project life cycle.
2. Product Architecture and Design
By using an SRS as a base template for the product architecture, architects can effectively deliver abackend product designaccording to feasibility and preliminary requirements.
Based on the requirements outlined in the SRS, typically more than one design approach is proposed and documented in the design document specification (DDS).
Eventually, the DDS is reviewed by all major project stakeholders, and based on critical parameters such as risk assessment, product robustness, budget and time constraints, and design modularity, the most viable architectural approach is selected.
The design approach in a secure software development life cycle is comprehensive.
It clearly defines all architectural modules of the product along with its communication with external and third-party modules outside the internal architecture via data flow illustrations.
3. Test Planning
In a secure software development life cycle, a test plan outlines:
The strategy used to test an application
Resources that will be used
The potential limitations of the testing, and
The projected schedule of the testing activities.
The quality assurance team lead will typically undertake test planning and resource allocation/assurance during this stage.
A test plan generally includes the following:
An introduction or brief overview of the test plan document
Expectations about business and technical constraints while testing the software
Comprehensive list of test cases to be included in testing the application
Approach to be used during software testing
Deliverables to be fulfilled and tested
Resources allocated for application testing
Potential all-around risks involved during the testing process
Schedule of tasks and milestones to be achieved within the testing time frame
Now it’s time to build and develop the product!
In this stage of the secure software development life cycle, code development is executed in compliance with the DDS.
As long as the design/architecture was performed in a detailed and organized fashion, code generation can be accomplished without many logistical hurdles.
It’s imperative that developers follow the coding guidelines as defined by their organization and program-specific tools, including the compilers, interpreters, and debuggers that are used to streamline the code generation process.
Various high-level programming languages such as C, C++, Pascal,PHP, andJavaare typically implemented for application development.
Regardless, the chosen programming language is entirely dependent upon the type of software, its industry use cases, and the technical specifications of the project.
5. Product Testing and Results
After several rounds of code review and quality assurance, product testing can be implemented in the secure software development life cycle.
It’s important to note that this stage is usually a subset of all stages in modernized SDLC models.
In other words, testing should be actively streamlinedin real-timethrough each step of the SDLC to ensure a sustainable development process.
However, this fifth stage alone is atesting onlystage of the product where critical defects are effectively reported, tracked/localized, fixed, and retested for final deployment and redeployment.
This rinse and repeat process is repeated until quality standards are satisfied as defined in the SRS.
6. Release in the Market and Maintenance
Once your organization’s product has undergone quality assurance and testing, the product is ready to be formally released into the appropriate market.
Depending on your organization’s market-level strategy, the product may first be released into a limited segment/sector of the primary market before being tested in a real business environment.
Otherwise, many startups and corporations release their product into cold water andreview customer feedbackin order to continuously optimize product features and software usability.
How Do You Make an SDLC Secure?
You can make a SDLC more secure by adding extra security measures to the existing groundwork of your SDLC development process.
For example, a tech leader could write, draft, and enforce security requirements alongside the collection of functional requirements in the SDLC.
And during the architecture and design phase, you can perform a risk analysis to target specific vulnerabilities.
A variety of secure software development life cycle models have been proposed and effectively enforced in modern development frameworks.
Here are a few of them:
NIST 800-64:Developed by the National Institutes of Standards and Technology, the guidelines provide security considerations and parameters within the SDLC to be observed by U.S. federal agencies.
MS Security Development Lifecycle (MS SDL):Proposed by Microsoft in association with the phases of a classic SDLC, the MS SDL is one of the first of its kind and provides dependable security considerations that work for most modern development pipelines.