OpenRDP

OpenRDP is an open‑source implementation of the Remote Desktop Protocol (RDP) that allows clients to connect to Windows or other desktop environments over a network. The project began in 2017 as a lightweight alternative to larger RDP server suites, aiming to provide a modular design that could be integrated into embedded devices, virtual machines, and cloud services. It supports RDP version 8.1 and includes optional extensions for Unicode and multi‑monitor displays.

The core of OpenRDP is written in C, using the POSIX API for portability. It relies on the Secure Channel (Schannel) or OpenSSL for TLS authentication, and supports both password and certificate‑based logins. The code base is structured into layers: a front‑end protocol handler, a back‑end graphics renderer that can use SDL or DirectX, and a plug‑in system for extensions such as clipboard sharing or audio redirection. This architecture allows developers to replace or upgrade parts of the stack without affecting the whole system.

OpenRDP is released under the Apache 2.0 license, which encourages both commercial and non‑commercial use. A growing community maintains the project through GitHub, where issues and pull requests are managed by core contributors. Regular releases include bug fixes, performance improvements, and support for the latest RDP security features. Documentation consists of a developer guide, API reference, and user‑manual examples that demonstrate setting up self‑hosted RDP servers on Linux and Windows.

In practice, OpenRDP is used in scenarios where a minimal footprint and high configurability are required. Examples include thin‑client deployments in education, remote access solutions for industrial control systems, and virtual desktop infrastructure (VDI) environments that need tight integration with existing authentication services. Its design prioritizes security, interoperability, and ease of use, making it a popular choice for researchers and developers building custom remote‑desktop solutions.