Towards a Commercial IP Security Option

The TCP/IP protocol suite has long had security options for military use. These provide for security labeling and compartmentalization. Unfortunately, these options are of little use in the civilian world, especially since they rely on trusted hosts to create the proper labels. We define two mechanisms, closed user groups and encryption protocol based on SP3, for use in the commercial sector. Both mechanisms are designed to be implemented primarily in IP gateways, and place minimal requirements on hosts.