TCP-AuthN: An Approach to Dynamic Firewall Operation in Grid Environments

Grid computing provides users with transparent access to substantial compute and storage resources. Up to now the main focus lay in the development of Grid infrastructures and the development of services providing access to grid resources. This leads to a negligence of security aspects, which, for example, leads to the recommendation of open wide port ranges on firewalls protecting the Grid resources. In this paper we present an approach for a dynamic firewall operation facilitated by a strong inline authentication for every TCP connection. The presented approach, which is based on X.509 certificates and public-key encryption uses TCP segments exchanged during the TCP three-way handshake between the client and the server to transport user authentication information. Firewalls on the path use this authentication information to authorize the connection. To distinguish the authentication information in the TCP segments from application data a new TCP option tcpauthn is introduced.