1. A system for assisting a user in configuring a network access node, the system comprising: a web based installation wizard; a processor; an inference engine coupled to the installation wizard and the processor and designed to be coupled to at least one configuration memory area; a port scanner coupled with the processor that is triggered by the installation wizard and is designed to scan internal ports in end user computing devices connected to the network access node and to determine the port number of each internal port that is in open state and to create for each open internal port an instance of an external port having the same port number as the open internal port and to store in one of the configuration memory areas private IP addresses to the end user computing devices together with the port numbers of each open internal port and each external port; a knowledge base coupled to the inference engine and the processor, wherein said wizard is for guiding the user to provide input to the system; and said inference engine is configured: for receiving said input, to retrieve stored information from the knowledge base, to process said input and stored information and to generate and store configuration data according to user requirements on the system in said at least one configuration memory area; and the wizard and the inference engine supporting the user to configure end user computing devices, including security level, connected to network access node from the information in the knowledge base through the processor.