Modeling and Verifying Data Access Mechanism of NLSR Trust Model

As a leading architecture of Information-Centric Networking (ICN), Named Data Networking (NDN) plays an important role in the future network construction. NDN retrieves and identifies a data packet according to the packet's name instead of its IP address. Conventional protocols of TCP/IP Internet are unsuitable for NDN. Therefore, Named-data Link State Routing protocol (NLSR) is proposed as an intra-domain routing protocol for NDN. Although NLSR applies a five-layer trust model to guarantee its data security, there are still a lot of security issues in its data access mechanism, such as the fake and leakage of data. In this paper, we apply Communicating Sequential Processes (CSP) to formalize this mechanism. Using Process Analysis Toolkit (PAT), we verify four properties, including deadlock freedom, data availability, data security and data decryption. According to the verification results, the trust model cannot protect the data from fake and leakage once intruders appear. We adopt a method similar to digital signature in the first improved model. However, the process of obtaining keys still needs to be executed multiple times during the verification of a data packet. To further accelerate the key fetching and verification process, all the keys, needed to validate a data packet, are packaged in a special packet of the second improvement.