Search

For MPLS VPN (Multi-Protocol Label Switching Virtual Private Network) not suitable for the complex business logic and application with high security requirements because of its lack of providing encryption and certification, a scheme of enhancing MPLS VPN QoS is proposed. It uses the method based on "Log-infinitely Divisible Cascades", realizes fine-grained security service strategy by integrating VPN and IPsec (IP security) and using cryptographies such as encrypted authentication, etc. Simulation results show that the proposed scheme increases the safety factor to clients and ensure the need for QoS of the application of high-end users.

As a distributed process calculus with localities and mobility of computational entities, Seal calculus is playing an important role in expressing key features such as security and mobility of Internet programming directly. However, little implementation technique proposed for the calculus, partly due to the complication of mobile computation, which fusions three important techniques: concurrency, distribution and mobility at the same time. The abstract machine PSN for a distributed implementation of the Seal calculus is presented. In PSN the logical structure of a seal system and its physical distribution are separated which induces a more simple and clear implementation. Moreover, an operational semantics description of the Seat calculus based on PSN is given.