Chapter 9 - VulnsThreats Flashcards
multitasking
handling two or more tasks simultaneously, managed by OS.
multiprocessing
multiprocessor computing system harnesses power to complete the execution of a single application.
Symmetric multiprocessing (SMP)
single computer with multiple processors treated equally and controlled by one OS. Adept at processing simple operations at extremely high rates.
Massively Parallel Processing (MPP)
house hundreds or thousands of processors, each with own OS and memory/bus resources. Used in computational-based research.
Multiprogramming
psuedosimultaneous execution of two tasks on single processor coordinated by OS to increase operational efficiency. Rare and obsolete. Used on mainframes. Requires special code.
Multithreading
permits multiple concurrent tasks to be performed within a single process. Used in apps where frequent context switching between multiple active processes consumes excessive overhead and reduces efficiency.
Before security modes can be deployed
§ Hierarchical MAC environment
§ Total physical control over which subjects can access the computer console
§ Totally physical control over which subjects can enter into the same room as the computer console.
dedicated mode
single state system. 3 requirements:
§ Each user must have security clearance that permits access to all information processed by the system.
§ Each user must have access approval for all info processed by system.
§ Each user must have valid need to know for all info processed by the system.
system high mode
§ Each user must have valid security clearance that permits access to all info processed by system
§ Each user must have access approval for all info processed by the system.
§ Each user must have a valid need to know for some info processed by the system but not necessarily all info processed by system.
compartmented mode
§ Each user must have valid security clearance that permits access to all info processed by system
§ Each user must have access approval for all info they will have access to on the system.
§ Each user must have valid need to know for all info they will have access to on the system.
Programmable Read-Only Memory (PROM)
□ chip contents aren’t burned in.
□ Once data written to PROM, no more changes.
□ Provides software developers with opportunity to store info permanently on high-speed customized memory chip.
□ Commonly used for hardware apps where custom functionality is necessary.
Erasable Programmable Read-Only Memory (EPROM)
□ Developers want to tinker with code.
□ Small window when illuminated with special UV light that erases chip
Electronically Erasable Programmable Read-Only Memory (EEPROM)
□ Uses electric voltages delivered to pins of the chip to force erasure. Don’t have to be removed to erase.
Cache RAM
□ Number of caches that improve performance by taking data from slower devices and temporarily storing it in faster devices when repeated use is likely.
□ Processor contains onboard cache of extremely fast memory (level 1 cache)
Level 1 backed up by static RAM cache on separate chip (level 2 cache)
Distributed control systems (DCSs)
§ Found in industrial process plans where need to gather data and implement control over large scale environment from single location is essential
§ Controlling elements are distributed across monitored environment, centralized monitoring location sends commands out of those localized controllers while gathering status and performance data.
