2025-08-31
Auth0: Authentication as a Service, or “Just Pay”
Introduction
So far, we’ve discussed solutions that give you full control but demand effort. Auth0 offers a different path: outsourcing authentication entirely. “We’ll handle it for you,” says Auth0 — “just connect to our API.” It’s the perfect choice for those who don’t want to moonlight as DevOps engineers.
The Big Promise
The core message of Auth0 is simplicity. The service promises that you can add user login in minutes without writing a single line of backend code. Its key advantages:
2025-08-30
FreeIPA: The Untamed Titan of Enterprise Identity
Introduction
While Keycloak and FusionAuth focus on the web, FreeIPA operates on a different level. It’s not just an authentication server. It’s an integrated solution for identity management and security policies in UNIX/Linux environments. It’s not designed for quick web app integration but for building centralized access control at an enterprise scale. If your infrastructure consists of many Linux servers, this tool is your ally.
2025-08-29
FusionAuth: Challenging the Giants with an API Focus
Introduction
While Keycloak may feel like a heavyweight titan built for the enterprise world, FusionAuth enters the arena with a much more developer-friendly agenda. This service positions itself as a solution built by developers for developers. It promises to be simple, fast, and most importantly, manageable through a clean, well-structured API. Sounds like a relief after wrestling with complex documentation.
The Big Promise
The core message of FusionAuth is “less configuration, more code.” It promises to save you from wrestling with dozens of XML files and bulky UIs. Instead, you should be able to integrate authentication in just a few hours using only API calls. Its arsenal includes:
2025-08-28
Keycloak: Open Source and Big Ambitions
Introduction
In a world where more and more services outsource user management, Keycloak offers a different path. This project is not just a set of login APIs. It is a full-fledged, self-sufficient authentication server that promises to relieve you from headaches with user management, protocols, and security. At the same time, it remains open source. Sounds like utopia, but let’s take a closer look.
2025-08-27
The Problem with Certificates at Scale
In previous articles, we discussed that OpenVPN uses certificates for authentication. This method is reliable but has significant drawbacks:
- Inconvenience for users: Each user must manually receive and install their own certificate.
- Complex management: When an employee leaves, their certificate must be revoked, which requires extra steps.
- Lack of centralization: Each service that requires access has its own authorization system.
The solution to this problem is using a centralized identity provider such as Keycloak.
2025-08-26
VPN: Not Just an “On” Button
For many users, a VPN is simply an “On” button. However, when it comes to building your own secure tunnel, it’s important to understand its architecture. OpenVPN is based on two key ideas: the client-server model and Public Key Infrastructure (PKI).
The Client-Server Model
The concept is simple:
- Server — the entry point into your secure network. It constantly “listens” for incoming requests and is ready to accept connections.
- Client — your device (laptop, phone) that initiates the connection to the server.
Once the server and client “agree,” a secure tunnel is created between them, and all traffic passes through it.
2025-08-25
OpenVPN: A Time-Tested Standard
Introduction
In a world where the speed and simplicity of WireGuard have become the new standard, OpenVPN remains one of the most reliable and flexible VPN protocols. It works both on traditional computers and on networking equipment, providing cross-platform compatibility and a high level of security. However, to understand how to use it, it is important to distinguish between the protocol itself and its client applications.
2025-08-23
When Control Matters Most
Services like Tailscale and NetBird are convenient, but they rely on a third-party control server responsible for authentication, key distribution, and route exchange. For those who, for security or privacy reasons, don’t want to entrust this function to anyone, there are two paths: Headscale and “pure” WireGuard.
Headscale: Your Own Tailscale
Headscale is a fully open-source implementation of Tailscale’s control server. It allows you to deploy your own Tailscale alternative on a VPS or server while still using the official Tailscale clients.
2025-08-22
When Zero-config VPN Means More Than Just Tailscale
Although Tailscale has become the benchmark for simplicity, it’s not the only player in the Zero-config VPN field. ZeroTier and NetBird offer similar functionality but with important architectural and ideological differences.
ZeroTier: A Virtual Ethernet Switch
ZeroTier is one of the first and most well-known services implementing the mesh network concept. It works on the principle of a virtual local network. Instead of relying on the WireGuard protocol, ZeroTier uses its own protocol and creates a virtual L2 switch (Layer 2) that unites all devices into a single local network. Each device gets an IP address from a virtual subnet and can “see” other devices as if they were connected to the same physical switch.
2025-08-21
What is Tailscale?
Tailscale is a VPN service that positions itself as a Zero-config VPN. It uses the WireGuard protocol to create a secure mesh network between all your devices. The key difference from other solutions is its simplicity. Instead of manually configuring tunnels and managing keys, Tailscale does all the work for you. All you need to do is install the app on each device and sign in.
How does it work under the hood?
When you sign in, the Tailscale client connects to the Control Plane server. This server essentially acts as the “brain” of the network:
