Abstract: A security system for distributed computer systems with a central computer and remotely located interactive terminals. The security system includes a master security control processor (SCP) which is associated with the central computer, and one or more slave SCPs, each of which is associated with one of the interactive terminals. Clearance at several security levels is required before communications between one of the remote terminals and the central computer is authorized. The security levels are implemented after communications are established to maintain only authorized access to the central computer. One of several unauthorized access modes are implemented when an unauthorized interactive terminal or SCP is identified. All data communicated between the master and slave SCPs is encrypted for security.

Abstract: A developer for black and white film comprising an active portion which includes from 16 percent to 23 percent by weight of hydroquinone, 23 percent to 30 percent by weight of a developer selected from the group consisting of Metol and Elon, 24 percent to 31 percent by weight potassium bromide and 24 percent to 32 percent by weight of sodium hydroxide such that the total percentage of these active ingredients comprises 100 percent of the active weight. Also included is a preservative portion such as sodium sulfite in amounts ranging from one-third to three times the weight of the active portion of the developer solution. Finally, sufficient water is present in the developer of this invention to provide an aqueous solution of the active portion of less than ten percent by weight active portion, based on the amount of water.