Method and system for establishing a security perimeter in computer networks

A method of providing a multi-level network security system for a computer device coupled to at least one computer network, comprising:

• placing a first secure network interface Unit (SNIU) within a communications stack of said computer device, said first SNIU communicating with other like SNIU devices on said network by establishing an association, wherein components of said network may be individually secure or non-secure, and whenever said first SNIU is configured to perform a plurality of security functions including:
• receiving said messages sent between said computer device and said network;
• converting said received messages to and from a format utilized by said network;
• identifying and verifying said computer device requesting access to said network;
• determining whether said association exists with another SNIU device;
• transmitting said messages received from said computer device when said association exists;
• and
• establishing an association with other like SNIU devices when said association does not exist.

A multi-level network security system for a computer device coupled to at least one computer network, comprising:

• means for placing a first secure network interface Unit (SNIU) within a communications stack of said computer device, said first SNIU communicating with other like SNIU devices on said network by establishing an association, wherein components of said network may be individually secure or non-secure, said first SNIU configured to perform a plurality of security functions and comprising:
• means for receiving said messages sent between said computer device and said network;
• means for converting said received messages to and from a format utilized by said network;
• means for identifying and verifying said computer device requesting access to said network;
• means for determining whether said association exists with another SNIU device;
• means for transmitting said messages received from said computer device when said association exists;
• and
• means for establishing an association with other like SNIU devices when said association does not exist.

A multi-level network security system for a computer device coupled to at least one computer network, comprising:

• a first secure network interface unit (SNIU) contained within a communications stack between a Network layer and a Data Link layer, said first SNIU communicating with other like SNIU devices on a network, wherein components of said network may be individually secure or non-secure, comprising:
• a network interface for receiving messages sent between a computer device and said network, said network interface configured to convert said received messages to and from a format utilized by said network;
• a message parser configured to determine whether an association exists between the first SNIU and another SNIU device;
• a session manager coupled to said network interface and configured to request access to and transmit said messages to said network, when said message parser determines said association exists;
• and
• an association manager coupled to said network interface for establishing an association with other like SNIU devices when said message parser determines said association does not exist.