Internet/Intranet firewall security - policy, architecture and transaction services

The development of Internet/Intranet security is of paramount importance to organisations that plan to gain the economic benefits from interconnection with the Internet. This paper commences by examining firewall policy, focusing on both network service access policy and firewall design policy. Various firewall architectures, ranging from simple packet filters through to screened subnets and proxy gateways, are then discussed. Finally, the various mechanisms by which transactions can be secured over the Internet/Intranet are covered. These include encrypted tunnelling, IPv6, point-to-point tunnelling protocol, secure sockets layer, secure electronic transactions and secure multipart Internet mail encoding.