The DisCAS system employs and interacts with multiple ELIMINOs distributed over the Internet to achieve a distributed-parallel computing environment. ELIMINO is a computer algebra system developed to support Wu’s method for computing characteristic sets of polynomials and for other related operations. GridPPI, an MPI-like interface for grid computing, could couple multiple computing tools distributed over grid to run complex computing problems. DisCAS combines grid technology, GridPPI and ELIMINOs to deliver high performance computing to Internet users. The overall ELIMINO, GridPPI, and grid technology, as well as the DisCAS architecture are presented. The way to access and apply DisCAS and related works are also discussed at last.