As computing technology evolved and the concept of linking multiple computers together into a “network” that could share data came into being, it was clear that a model was needed to define and enable those connections. Enter the OSI model in computer network idea.


This model allows various devices and software to “communicate” with one another by creating a set of universal rules and functions. Let’s dig into what the model entails.


History of the OSI Model


In the late 1970s, the continued development of computerized technology saw many companies start to introduce their own systems. These systems stood alone from others. For example, a computer at Retailer A has no way to communicate with a computer at Retailer B, with neither computer being able to communicate with the various vendors and other organizations within the retail supply chain.


Clearly, some way of connecting these standalone systems was needed, leading to researchers from France, the U.S., and the U.K. splitting into two groups – The International Organization for Standardization and the International Telegraph and Telephone Consultive Committee.


In 1983, these two groups merged their work to create “The Basic Reference Model for Open Systems Interconnection (OSI).” This model established industry standards for communication between networked devices, though the path to OSI’s implementation wasn’t as clear as it could have been. The 1980s and 1990s saw the introduction of another model – The TCP IP model – which competed against the OSI model for supremacy. TCP/IP gained so much traction that it became the cornerstone model for the then-budding internet, leading to the OSI model in computer network applications falling out of favor in many sectors. Despite this, the OSI model is still a valuable reference point for students who want to learn more about networking and still have some practical uses in industry.


The OSI Reference Model


The OSI model works by splitting the concept of computers communicating with one another into seven computer network layers (defined below), each offering standardized rules for its specific function. During the rise of the OSI model, these layers worked in concert, allowing systems to communicate as long as they followed the rules.


Though the OSI model in computer network applications has fallen out of favor on a practical level, it still offers several benefits:


  • The OSI model is perfect for teaching network architecture because it defines how computers communicate.
  • OSI is a layered model, with separation between each layer, so one layer doesn’t affect the operation of any other.
  • The OSI model offers flexibility because of the distinctions it makes between layers, with users being able to replace protocols in any layer without worrying about how they’ll impact the other layers.

The 7 Layers of the OSI Model


The OSI reference model in computer network teaching is a lot like an onion. It has several layers, each standing alone but each needing to be peeled back to get a result. But where peeling back the layers of an onion gets you a tasty ingredient or treat, peeling them back in the OSI model delivers a better understanding of networking and the protocols that lie behind it.


Each of these seven layers serves a different function.


Layer 1: Physical Layer


Sitting at the lowest level of the OSI model, the physical layer is all about the hows and wherefores of transmitting electrical signals from one device to another. Think of it as the protocols needed for the pins, cables, voltages, and every other component of a physical device if said device wants to communicate with another that uses the OSI model.


Layer 2: Data Link Layer


With the physical layer in place, the challenge shifts to transmitting data between devices. The data layer defines how node-to-node transfer occurs, allowing for the packaging of data into “frames” and the correction of errors that may happen in the physical layer.


The data layer has two “sub-layers” of its own:


  • MAC – Media Access Controls that offer multiplexing and flow control to govern a device’s transmissions over an OSI network.
  • LLC – Logical Link Controls that offer error control over the physical media (i.e., the devices) used to transmit data across a connection.

Layer 3: Network Layer


The network layer is like an intermediary between devices, as it accepts “frames” from the data layer and sends them on their way to their intended destination. Think of this layer as the postal service of the OSI model in computer network applications.



Layer 4: Transport Layer


If the network layer is a delivery person, the transport layer is the van that the delivery person uses to carry their parcels (i.e., data packets) between addresses. This layer regulates the sequencing, sizing, and transferring of data between hosts and systems. TCP (Transmission Control Protocol) is a good example of a transport layer in practical applications.


Layer 5: Session Layer


When one device wants to communicate with another, it sets up a “session” in which the communication takes place, similar to how your boss may schedule a meeting with you when they want to talk. The session layer regulates how the connections between machines are set up and managed, in addition to providing authorization controls to ensure no unwanted devices can interrupt or “listen in” on the session.


Layer 6: Presentation Layer


Presentation matters when sending data from one system to another. The presentation layer “pretties up” data by formatting and translating it into a syntax that the recipient’s application accepts. Encryption and decryption is a perfect example, as a data packet can be encrypted to be unreadable to anybody who intercepts it, only to be decrypted via the presentation layer so the intended recipient can see what the data packet contains.


Layer 7: Application Layer


The application layer is a front end through which the end user can interact with everything that’s going on behind the scenes in the network. It’s usually a piece of software that puts a user-friendly face on a network. For instance, the Google Chrome web browser is an application layer for the entire network of connections that make up the internet.


Interactions Between OSI Layers


Though each of the OSI layers in computer networks is independent (lending to the flexibility mentioned earlier), they must also interact with one another to make the network functional.


We see this most obviously in the data encapsulation and de-encapsulation that occurs in the model. Encapsulation is the process of adding information to a data packet as it travels, with de-encapsulation being the method used to remove that data added data so the end user can read what was originally sent. The previously mentioned encryption and decryption of data is a good example.


That process of encapsulation and de-encapsulation defines how the OSI model works. Each layer adds its own little “flavor” to the transmitted data packet, with each subsequent layer either adding something new or de-encapsulating something previously added so it can read the data. Each of these additions and subtractions is governed by the protocols set within each layer. A perfect network can only exist if these protocols properly govern data transmission, allowing for communication between each layer.


Real-World Applications of the OSI Model


There’s a reason why the OSI model in computer network study is often called a “reference” model – though important, it was quickly replaced with other models. As a result, you’ll rarely see the OSI model used as a way to connect devices, with TCP/IP being far more popular. Still, there are several practical applications for the OSI model.


Network Troubleshooting and Diagnostics


Given that some modern computer networks are unfathomably complex, picking out a single error that messes up the whole communication process can feel like navigating a minefield. Every wrong step causes something else to blow up, leading to more problems than you solve. The OSI model’s layered approach offers a way to break down the different aspects of a network to make it easier to identify problems.


Network Design and Implementation


Though the OSI model has few practical purposes, as a theoretical model it’s often seen as the basis for all networking concepts that came after. That makes it an ideal teaching tool for showcasing how networks are designed and implemented. Some even refer to the model when creating networks using other models, with the layered approach helping understand complex networks.


Enhancing Network Security


The concept of encapsulation and de-encapsulation comes to the fore again here (remember – encryption), as this concept shows us that it’s dangerous to allow a data packet to move through a network with no interactions. The OSI model shows how altering that packet as it goes on its journey makes it easier to protect data from unwanted eyes.



Limitations and Criticisms of the OSI Model


Despite its many uses as a teaching tool, the OSI model in computer network has limitations that are the reasons why it sees few practical applications:


  • Complexity – As valuable as the layered approach may be to teaching networks, it’s often too complex to execute in practice.
  • Overlap – The very flexibility that makes OSI great for people who want more control over their networks can come back to bite the model. The failure to implement proper controls and protocols can lead to overlap, as can the layered approach itself. Each of the computer network layers needs the others to work.
  • The Existence of Alternatives – The OSI model walked so other models could run, establishing many fundamental networking concepts that other models executed better in practical terms. Again, the massive network known as the internet is a great example, as it uses the TCP/IP model to reduce complexity and more effectively transmit data.

Use the OSI Reference Model in Computer Network Applications


Though it has little practical application in today’s world, the OSI model in computer network terms is a theoretical model that played a crucial role in establishing many of the “rules” of networking still used today. Its importance is still recognized by the fact that many computing courses use the OSI model to teach the fundamentals of networks.


Think of learning about the OSI model as being similar to laying the foundations for a house. You’ll get to grips with the basic concepts of how networks work, allowing you to build up your knowledge by incorporating both current networking technology and future advancements to become a networking specialist.

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Computer Science and Cloud Computing: What Skills Are Needed for the Future
OPIT - Open Institute of Technology
OPIT - Open Institute of Technology
Oct 20, 2025 6 min read

More and more students are turning to careers in computer science, and it’s easy to see why. The world is becoming increasingly reliant on and powered by modern technology with every passing day.

Emerging innovations like artificial intelligence (AI) and cloud computing are set to change the face of countless industries. This means qualifications in computer science unlock the doors to countless job opportunities.

However, this is also a dynamic and rapidly changing field – a field that demands a distinct set of core skills to not only achieve success, but also future-proof your career for years to come.

The Importance and Value of Computer Science and Cloud Computing Qualifications

Official statistics show that the European cloud computing market is set to experience an astonishing compound annual growth rate (CAGR) of almost 23% in the coming years, moving from a value of €110 billion in 2024 to a lower-end estimate €250 billion by 2028, and it won’t stop there.

The same sort of growth is being seen across the full spectrum of computer science fields and industries, with emerging technologies like AI, automation, and edge computing all spearheading the surging value and importance of these sectors.

The increasing shift away from conventional computing towards cloud computing shows just how quickly the technological world changes and evolves. It also demonstrates the need for professionals with a wide and varied range of skills, plus the ability to adapt to rapidly changing situations.

Those who can bring these skills to the table, supported by a comprehensive education and effective computer science qualifications, can enjoy:

  • Entry into job markets that have exceptionally high levels of demand.
  • Diverse career opportunities in fields that range from AI and machine learning to computer engineering and software development.
  • Competitive salaries, with consistently high rates offered all around the world.
  • Job security and stability, given the ever-increasing significance of technology in the modern world.

Core Skills to Master for Long Careers in Computer Science

Next, let’s look into the actual specific skills that computer science students and aspiring leaders will need to master to secure their futures.

Programming Languages

Being able to work with code is the bedrock of almost any career in computer science. Aspiring scientists will need to master one or several programming languages, including Java for building business and web apps, Python for web development, and C++ for system programming.

Networks and Architectures

Computer scientists also need a strong core knowledge of the fundamentals of the computing world, like how networks function, the various protocols and architectures that control the flow of data from device to device, etc.

Algorithms and Data

Algorithms play a fundamental role in fields like AI and machine learning, so computer scientists must understand how different algorithms and data structures drive computing processes, problem-solving, and development.

Software Development

Computer scientists may spend much of their time working on development projects post-graduation, which may include apps for the web, business, mobile, and more. A strong understanding of the stages of the software development lifecycle and processes involved is, therefore, essential.

Cloud Computing

With cloud computing growing in importance, unlocking whole new fields, like software as a service (SaaS) and desktop as a service (DaaS), the computer scientists of tomorrow will also need to have intricate knowledge of how cloud computing works and the potential it holds.

Soft Skills

Along with the many technical skills listed above, computer scientists will also benefit from vital soft skills that will help them when collaborating with others, presenting their ideas, driving innovation in their chosen fields, leading teams, and managing projects. These skills include:

  • Being able to communicate effectively, both with fellow computer scientists and non-technical audiences as well
  • Analytical thinking and problem-solving skills that help scientists understand and respond to challenges
  • Adaptability, so that scientists can keep on learning, evolving their skill sets, and embracing new tech and ideas as they emerge
  • The ability to work as part of a team, often fundamental for large-scale computing projects
  • Attention to detail that allows you to spot that single line of code that needs fixing, or for tasks like debugging and data interpretation

Get the Best Start With a BSc in Computer Science at OPIT

We’ve seen the skills you need to succeed in computer science and cloud computing for years to come, but one question remains: where is the best place to gain these skills and acquire the necessary knowledge for genuine long-term success?

The answer: the Open Institute of Technology (OPIT).

An exclusively online learning platform specializing in computer science and digital business, OPIT offers a curated collection of online degrees for tomorrow’s technology leaders, including a Foundation Program for beginners, bachelor’s programs, and master’s degrees for the most experienced students.

Why Study at OPIT?

Advantages of studying with OPIT include:

  • Accessible and flexible online learning to suit your needs and pace
  • A focus on real-world applications of the skills and knowledge imparted
  • A leading team of top tutors and professors from diverse fields and nations
  • An international community of students with which to collaborate
  • Progressive assessment of skills and knowledge, as opposed to exam-heavy schedules

Those planning pathways into computer science and cloud computing are best served by OPIT’s BSc in Computer Science program.

Lasting six terms and worth 180 ECTS credits, this fully remote, online, and accredited undergraduate degree was developed with insights from industry leaders, academics, and employers within the IT industry.

It equips graduates with both the fundamental theoretical knowledge they need to succeed in technology, as well as the practical skills required to enter the world of work and immediately innovate in fields like programming, cybersecurity, data science, AI, and cloud computing.

Like other courses and programs available at OPIT, this BSc in Computer Science provides students with a flexible learning program involving a mixture of recorded and engaging live content, progressive assessment, fast-track options for those who study at a faster pace, and round-the-clock accessibility to tutors and fellow learners.

If you feel that computer science or cloud computing is the right path for you, and you want to secure the foundational skills you need to succeed, consider the OPIT BSc in Computer Science to help you achieve your dreams.

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My Journey Into Responsible AI at OPIT: Inauguration Day & Why I Chose This Path
OPIT - Open Institute of Technology
OPIT - Open Institute of Technology
Oct 20, 2025 6 min read

On September 8, 2025, the Open Institute of Technology (OPIT) officially inaugurated its 2025/26 academic year, welcoming a whole host of new students into the institute, ready to gain the skills and knowledge they need to be the tech industry leaders of tomorrow.

Faculty members, guest speakers from around the world, and hundreds of students from over 100 nations were all in attendance at the online inauguration event. Among them was one new student on the MSc in Responsible AI program: Rem Lampa, also known by his online alias, Kuya Dev.

A Filipino podcaster, speaker, and developer, Kuya Dev documented the inauguration experience in a YouTube video, sharing his thoughts on the event. Here’s a detailed look at his experience, showing the welcoming and effective way in which new OPIT students are brought into the institute from the first day.

An Overview of the Inauguration Event

The latest OPIT inauguration event was one to remember, with the institute celebrating several notable milestones. These included the first graduation of the MSc in Applied Data Science and AI program, and the unveiling of new industry connections and corporate partners offering opportunities for graduates.

Various guest speakers were in attendance, including the former Italian Minister of Education and current OPIT Rector, Professor Francesco Profumo, plus the CEO of Malta’s accreditation authority MFHEA, Dr. Rose Anne Cuschieri.

OPIT founder, Riccardo Ocleppo, also took to the stage to highlight the transformative role of education and the unique possibilities offered by the online-only OPIT degrees, stating:

“When we launched OPIT in 2022, we wanted to prove that an online degree could be rigorous, international, deeply connected to the world of work, and engaging. Three years later, we can already see results. This year alone, 300 new students are joining us, representing 98 nationalities.”

Those hundreds of new students were also, naturally, in attendance for their big inauguration day, welcomed into the institute’s various BSc and MSc programs in specialties like Computer Science, Digital Business, Digital Business and Innovation, and Cybersecurity.

Introducing Rem ‘Kuya Dev’ Lampa

As mentioned, one of the new students joining was vlogger and podcaster, Kuya Dev.

Already boasting extensive experience and technical expertise in the computing world, Kuya Dev has founded several tech communities, including Tech Career Shifter Philippines and Server-Side JavaScript.

He describes himself as an advocate for responsible AI and tech practices, and once gave a powerful TEDx talk about the negative potential impacts of artificial intelligence (AI), including its large carbon footprint and involving exploitation of workers in emerging nations. So, it was only fitting that he signed up for OPIT’s MSc in Responsible AI.

The MSc in Responsible AI Program

A postgraduate program lasting three or four terms (between 12 and 24 months, total), OPIT’s MSc in Responsible AI is an accredited program that combines technical skills with a core focus on the ethical implications of AI technology.

It explores real-world use cases of AI and ways in which this exciting and powerful technology can be used responsibly and sustainably, emphasizing its potential for both positive and negative change in areas such as the environment and society as a whole.

Students of this program enjoy all the usual benefits that come with studying at OPIT, like flexible-paced learning, tutors available on a daily basis, a dynamic and engaging online learning environment, and fair, progressive assessments over time.

Those who graduate can move into careers in AI Application Development, AI Research, and AI Business Consulting.

Highlights and Impressions of Kuya Dev’s Inauguration Experience

Inauguration is always a special moment in any student’s academic journey as they take their first tentative yet exciting steps towards new knowledge and skills that can unlock their potential and accelerate their development.

It can even be a “make-or-break” moment in which students can either feel welcomed, empowered, and eager to begin their studies, or, conversely, experience feelings of worry, doubt, or regret if the inauguration lacks the spark they were hoping to feel.

Fortunately, Kuya Dev and his many fellow new OPIT students had a very positive experience at the inauguration event, with the vlogger calling it both “very fruitful” and “very insightful.” Some of the specific highlights he mentioned included:

An International Community

Early in the inauguration event, Kuya Dev heard from Professor Francesco Profumo about how OPIT was welcoming students from over 90 countries.

This, for Kuya Dev and for so many other students, is one of the big perks of studying with OPIT. It allows students to meet, engage, and exchange with people from dozens of different backgrounds, cultures, and communities, learning new ways of thinking and collaborating.

Real World Applications

The OPIT inauguration also focused on another of the university’s key features: a focus not merely on imparting knowledge to students or making them memorize facts, figures, and theorems, but actually teaching them how to apply that knowledge and ideas to real-world uses.

Kuya Dev commented on how other universities that he had considered attending appeared more conventional and limited in their approach, and also shared his excitement and enthusiasm at OPIT’s unique approach, focusing more on genuine industry collaboration and real-life scenarios.

Inspiring Speakers

The vlogger and podcaster also commented on the various key speakers who hosted the event. He was pleased to see that they were not only academically oriented but also all had real-world experience and a diverse range of working backgrounds in fields like politics.

This, too, is part of what makes OPIT different. It features a winning team of international tutors, professors, and experts from diverse fields, including the aforementioned former Italian Education Minister, education executives, research chairs, digital content creation specialists, and more.

Graduate Experiences

Finally, Kuya Dev noted how several OPIT graduates spoke to those about to follow the same path they did, including students from nations as diverse as the U.S., Italy, and Nigeria.

They all shared their experiences and detailed what they enjoyed most about studying with OPIT, including key factors such as professors who took the time to get to know their students, as well as the depth of the topics and knowledge covered in each course.

A Successful First Step Into OPIT Education

All in all, the recent inauguration event was a major success for all involved, giving students like Kuya Dev the ideal introduction to life and study with OPIT. He, like so many of his new fellow students, left the event eager and excited to expand their knowledge and broaden their horizons in unique ways that only OPIT can provide.

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