Infrastructure, Systems, and Connectivity
Half-Duplex and Full-Duplex are the two primary data transmission modes in Ethernet networks. Half-Duplex allows transmission or reception in only one direction at a time and uses CSMA/CD, while Full-Duplex enables simultaneous sending and receiving, completely eliminating collisions. This article explains the differences between these two modes, how to configure them on Cisco switches and routers, their advantages and disadvantages, and practical examples.
Set Theory is the mathematical foundation of the relational database model. Concepts such as Union, Intersection, Difference, and Cartesian Product are directly implemented in SQL. Understanding these concepts helps database engineers write more logical, efficient, and powerful queries. This article explains the relationship between Set Theory and relational databases, the main operations, and practical SQL examples.
Collision Domain and Broadcast Domain are two fundamental concepts in Ethernet network design and troubleshooting. A Collision Domain is the portion of a network where packet collisions can occur, while a Broadcast Domain is the portion where broadcast frames are flooded to all devices. Cisco switches separate Collision Domains but not Broadcast Domains (unless VLANs are used), whereas routers separate both. This article explains these concepts in detail, their behavior in Cisco switches and routers, and practical examples.
Containers have transformed modern software deployment by making applications faster, lighter, and more portable than traditional virtual machines. This article explains why containers emerged, how they differ from virtual machines, and the role Docker played in making them accessible to everyone.
Docker sits at the center of the modern container ecosystem, but its success depends on open standards and community-driven projects working behind the scenes. This article explains the history of Docker, Inc., how the Docker platform works, and the role of the OCI, CNCF, and the Moby Project in shaping container technology.
There are several ways to get Docker running on your machine, from the full-featured Docker Desktop to lightweight VM-based and native Linux installations. This article walks through the main installation options and how to verify Docker is working correctly.
The Docker Engine is a modular system built from small, specialized components rather than one giant program. This article breaks down how containerd, runc, and shims work together to create and run containers, and how the Open Container Initiative shaped this architecture.
A Docker image is a read-only package containing everything an application needs to run, built from stacked layers rather than a single file. This article covers how images work, how naming and tagging function, and why digests matter more than tags for reliability.
Containers are lightweight, run-time instances of images that behave very differently from virtual machines, even though both aim to isolate and run applications. This article compares the two models and walks through starting, inspecting, debugging, and applying restart policies to containers with Docker.
Turning application source code into a runnable container image follows a consistent five-step process in Docker. This article walks through writing a Dockerfile, building an image, pushing it to a registry, and running it as a container, using a simple Node.js app as the example.
Large container images mean slower deployments and a bigger attack surface. This article explains how multi-stage builds keep production images lean, and how Buildx and BuildKit make it possible to build images for multiple CPU architectures at once.
Modern applications are often built from multiple connected services rather than a single container, which makes manual deployment complex and error-prone. This article explains how Docker Compose uses a simple YAML file to define, deploy, and manage multi-container applications with a single command.
