This article presents a new communication library developed to ease the implementation of both asynchronous and synchronous iterative methods. A mathematical and algorithmic framework about fixed-point methods is described to introduce this class of parallel iterative algorithms, although this library can be used for a larger class of parallel algorithms. After an overview of the main features, we describe detailed implementation aspects arising from the asynchronous context. While the library is mainly based on top of Message Passing Interface library, it has been designed to be easily extended to other types of communication middleware. Finally, some numerical experiments validate this new library, used for implementing both a classical parallel scheme and a sub-structuring approach of the Jacobi iterative method.