Network security systems, namely, network access server hardware for creating and maintaining firewalls, and VPN (virtual private network) hardware and network access server operating software for the foregoing; Computer hardware and software for creating, facilitating and managing secure remote access to and communication with remote computers, local area networks, virtual private networks, wide area networks and global computer networks; VPN hardware, namely, virtual private networks gateways; remote access servers, namely, computer servers, communications servers, internet servers; remote access adapters, namely, electrical adapters; electrical connectors, namely, application connectors providing secure access to computer applications; computer hardware and software for enhancing the performance of a plurality of servers connected together by a network; computer software and computer programs for controlling and optimizing information flow between TCP/IP routers and computing devices clustered on a local area network