The CyaSSL embedded SSL library is a lightweight SSL library written in ANSI C and targeted for embedded and RTOS environments, primarily because of its small size, speed, and feature set. It is commonly used in standard operating environments and cloud services as well because of its royalty-free pricing and excellent cross platform support. CyaSSL supports industry standards up to the current TLS 1.2 and DTLS 1.2 levels, is up to 20 times smaller than OpenSSL, and offers progressive ciphers such as HC-128, RABBIT, and NTRU.
PolarSSL is a light-weight cryptographic and SSL/TLS library written in C. PolarSSL makes it easy for developers to include cryptographic and SSL/TLS capabilities in their (embedded) applications with as little hassle as possible. Loose coupling of the components inside the library means that it is easy to separate the parts that are needed, without needing to include the total library. PolarSSL is written with embedded systems in mind and has been ported on a number of architectures, including ARM, PowerPC, MIPS, and Motorola 68000. The source is written to have very loose coupling, enabling easy integration of parts in other software projects. Very loosely coupled cryptographic algorithms for MD2, MD4, MD5, SHA1, SHA-256, SHA-512, AES, Camellia, DES, Triple DES, ARC3, and RSA are included.
The yaSSL Embedded Web Server is a fast, embeddable, and easy-to-configure Web server with a strong focus on portability and security. The Web server offers SSL/TLS (HTTPS) support built-in through the CyaSSL embedded SSL Library. With a footprint size of less than 100kB with SSL enabled (or 40kB without SSL) and a simple and clean API, the yaSSL Embedded Web Server was designed to fit perfectly into resource-constrained embedded environments. While maintaining a small size and fast speeds, the yaSSL Embedded Web Server offers a full feature set to give you the maximum amount of freedom and flexibility when developing your project.