Abstract:
A COMPUTER MEMORY SYSTEM IN WHICH THE DATA IS TRANSFERRED BETWEEN HIGH-SPEED LOCAL STORAGE AND ONE OR MORE LEVELS OF A LARGER LOW SPEED STORAGE WHEREIN ALTERED DATA IS REWRITTEN IN HIGH-SPEED STORAGE IMMEDIATELY AND IN THE LOWSPEED STORAGE ON A CYCLE STEALING BASIS. CONTROLS ARE PROVIDED SO THAT WHEN A SMALL SEGMENT OF DATA IN A PARTICULAR BLOCK OR PAGE IN HIGH-SPEED STORE IS ALTERED AND INDICATOR IS SET. WHEN MEMORY BUSS TIME IS AVAILABLE TO THE LOW SPEED OR BACKUP STORE THESE INDICATORS WILL BE CHECKED AND WORDS OR LINES REWRITTEN IN SAID BACKUP STORE AS LONG AS A HIGHER PRIORITY JOB IS NOT ENCOUNTERED. WHEN IT IS DESIRED TO REPLACE A COMPLETE PAGE IN HIGH-SPEED STORAGE, INDICATORS FOR THAT PAGE ARE CHECKED AND ALL ALTERED WORDS ARE REWRITTEN IMMEDIATEDLY IN THE BACKUP STORE ON A HIGH PRIORITY BASIS AFTER WHICH THE PAGE IN THE HIGH-SPEED STORE MAY BE OVERWRITTER WITH NEW DATA FROM THE BACKUP STORE.
Abstract:
A light pen arrangement is described wherein the light pen has three degrees of freedom, viz. two-dimensional translation in the (X,Y) plane of a cathode ray tube screen and rotation about the projection of its own longitudinal axis to the normal of the screen. To sense the angular position of the light pen, at least two independent light sensitive elements, i.e., fiber optic bundles are required, the latter being suitably provided by dividing the bundle of fiber optics emerging from a single light pen into at least two separate groups and having photosensitive transducer respectively associated with each of the separate groups. When the light pen is placed on the screen and its presence there is sensed, an (X,Y) value pair is stored for the location of each light sensitive area of the light pen, i.e., each of the aforementioned separate fiber optic groups. The storing is accomplished by having an electron beam draw lines or points in each light sensitive area and, receiving in response thereto, interrupts for points or lines in the field of view of each fiber optic group, the (X,Y) coordinate of each point or line causing an interrupt and the fiber optic group that picked up the interrupt is now known to the computer or other control arrangement controlling the cathode ray tube. The computer or control arrangement can then compute the (X,Y) location of the light pen as the centroid of the individual areas and the angular position of the pen.
Abstract:
An operating system authenticator for determining if an operating system being loaded in a computer is valid. A user's identification code or secret key which is unique to the operating system, and a verifier value which is a predetermined function of a valid operating system and the identification code are respectively stored. A hash function, which is a function of the operating system being loaded and the identification code, is generated by the authenticator. After the operating system is loaded, the hash function is used as an authenticating value and compared with the verifier value for determining the authenticity of the loaded operating system.
Abstract:
OPERATING SYSTEM AUTHENTICATOR of The Disclosure An operating system authenticator for determining if an operating system being loaded in a computer is valid. A user's identification code or secret key which is unique to the operating system, and a verifier value which is a predetermined function of a valid operating system and the identification code are respectively stored. A hash function, which is a function of the operating system being loaded and the identification code, is generated by the authenticator. After the operating system is loaded, the hash function is used as an authenticating value and compared with the verifier value for determining the authenticity of the loaded operating system.
Abstract:
1534189 Monitoring storage accesses INTERNATIONAL BUSINESS MACHINES CORP 16 Nov 1976 [4 Dec 1975] 47656/76 Heading G4A A memory 12 or 32 is divided into envelopes 12a-12f or 34 each of which has an associated storage element 18 or 30 in which a time stamp from a clock 20 is recorded each time that envelope is accessed. Time stamp recording is automatic so that by reading the time stamps for particular memory elements a user can determine if any unauthorized access has been made since the last authorized access. Memory 12 may be a random access memory of which time stamp registers 18 form a part. Memory 32 may be a magnetic disc unit having two envelopes 34 and associated time stamp words 30 per track. The arrangement is described in detail in the context of a virtual memory system in which the time stamp registers 18 form an associative memory which is searched by block registers and stores time stamps together with indications as to whether the relevant accesses were for read or write. Any time stamp register 18 can be read by a special instruction FSM which loads the contents of the required register 18 into a specified register in the CPU 10. Each data channel 38 has a corresponding time stamp register 36 which is loaded with a time stamp word 30 whenever a disc envelope is moved via the channel to a memory 12 envelope (the appropriate register 18 and word 30 also time stamped from clock 20). The register 36 contents can be loaded into a specified CPU register by a special instruction FSC. Data envelope transfer between disc 32 and memory 12 takes place serially by word via a shift register buffer.
Abstract:
A data security system employing an automatic time-stamping mechanism for stamping a time accrued in a data storage area or register associated with each envelope or block of a memory or for each data channel of an auxiliary storage device, such that each access or data updates the appropriate time stamp in the memory of storage device. A first instruction provides the fetch of the time stamp with regard to the main memory, and a second instruction provides the fetch with regard to information contained in the data channel corresponding to the auxiliary storage device. For every envelope of a memory, there is a time stamp tag register associated with it. Similarly, there is a time stamp register associated with every data channel. Whenever an envelope of memory is accessed, the time stamp in the form of a unique binary number from a clock, indicating the time of day, is inserted into the tag register associated with that envelope. Examination of the contents of each tag register enables determination of whether there has been access to an envelope up to the present time. A full memory address register is used to access data in the memory while only special high order bits of the memory address register are used to access the time stamp associated with the envelope. The system provides a mechanism which automatically marks blocks of data as they are accessed and cannot be bypassed by altering the program.