IT Fundamentals

PaaS vs IaaS vs SaaS: Choosing the Right Cloud Model Cloud models describe how you use computing resources. The three common options are IaaS, PaaS, and SaaS. Each model shifts some work from you to the provider. The choice affects control, speed, and cost. With clear goals, you can pick the right model for your team. What each model covers IaaS: You get virtual machines, storage, and networks. You decide the operating system, runtimes, and data. The provider handles hardware, power, and cooling. Example: AWS EC2, Azure Virtual Machines. PaaS: The platform runs the runtime and middleware. You deploy code, and the system scales and updates for you. You focus on features, not server maintenance. Example: Heroku, Google App Engine. SaaS: You use software hosted by the provider. No setup or maintenance of the app is needed. Your job is to use the tool and manage data. Example: Gmail, Salesforce. When to choose ...

Network architecture and routing protocols explained Network design shows how devices connect and talk to each other. It helps decide where to place hardware, which links to use, and how to keep data moving even if a part of the system fails. On one end you have a home Wi‑Fi setup; on the other, a global internet connection with many sites. Each layer has goals for speed, reliability, and security. ...

Cloud Infrastructure 101: IaaS, PaaS, and SaaS in Action Cloud services come in three common models. IaaS, PaaS, and SaaS help teams control, deploy, and use software in different ways. Understanding who handles what makes it easier to design solutions that fit goals and budgets. IaaS: Infrastructure as a Service IaaS offers raw computing resources—virtual machines, storage, and networks. You install and manage the operating system, middleware, and applications. The provider takes care of the physical servers, power, and cooling. This model gives you the most control, but also the most responsibility. ...

Communication Protocols: The Language of Modern Networks Networks run on rules. Protocols are the common language that devices use to talk, from the moment a packet is created to its final destination. They decide how data is formatted, when messages are sent, and how errors are handled. Understanding them helps you see why the web feels fast, reliable, and a bit magical. What is a protocol? A protocol is like grammar for a conversation. It sets structure and order, so two machines can exchange data correctly even if they are far apart. In networks, protocols are layered. Each layer adds rules that the layer above can rely on, while hiding complexity from the user. ...

Networking Fundamentals: Protocols, Layers, and Security Networking is about devices talking to each other. It uses a set of rules called protocols, and a layered approach that helps data travel safely from sender to receiver. If you understand these basics, you can troubleshoot problems and make smarter choices about devices and services. Understanding protocols helps explain how information moves across the internet. Different layers and rules handle different tasks, from finding a page to delivering a file. ...

Understanding the Core of Modern Operating Systems Every app you run relies on the operating system to manage work. The OS coordinates programs, memory, and devices so tasks run without crashing into each other. It also protects your data from accidental or malicious access. This post breaks down three key ideas: processes, scheduling, and security, with plain language and simple examples. Processes and their life cycle A process is a program in execution. It has its own memory, a program counter, and a set of resources. The OS creates a new process when you launch an app, and it can end when the app closes. Most systems track states such as new, ready, running, waiting, and terminated. Some call zombie processes a process that finished but still has a place in the system table. Keeping processes reasonably small helps the OS switch between them quickly. ...

Networking Basics for Cloud Architects In cloud projects, networking is the backbone that connects services, people, and partners. A clear network design helps apps scale, keeps data safer, and makes troubleshooting easier. This article covers the core ideas every cloud architect should know, from how addresses are planned to how to connect networks securely. Key building blocks These are the main parts you will use in most cloud networks: Virtual networks (VPCs or VNets) Subnets and segmentation Route tables and gateways NAT and outbound access Firewall rules and security groups Load balancers and DNS IP addressing with CIDR Private connectivity (VPN, ExpressRoute, Direct Connect) Peering and shared networks Observability: logs and metrics A simple pattern A common pattern is three tiers: public web in a front subnet, private app in a middle subnet, and a private data subnet. The web server talks to the app, and the app talks to the database. The public subnet uses an Internet gateway; the private subnets stay hidden from the Internet. Outbound connections from private subnets go through a NAT device or NAT gateway so servers can reach external services without exposing themselves. ...