Domain 2: Memory and Remanence Flashcards
Data that persists beyond noninvasive means to delete it.
Data Remanence
Data most frequently used by the CPU
Cache Memory
CPU onboard memory
Register
Cache dedicated to a single processor core
Level 1/2 Cache
Cache shared between cores
Level 3 Cache
Cache located on the motherboard or on the GPU
Level 4 Cache
Memory that uses small latches called “flip-flops” to store bits
Fastest RAM
Static random-access memory (SRAM)
Memory that stores bits in small capacitors that hold a charge (representing 1 bit) or do not hold a charge (representing 0 bit)
Dynamic random-access Memory (DRAM)
ROM chip which contents aren’t burnt in during the manufacturing process. Instead allows the end user to burn in the chip contents later.
Once written no further changes are possible
Programmable read-only memory (PROM)
Category of PROM chips that allow content on a ROM chip to be erased
Erasable programmable read-only memory (EPROM)
Type of EPROM
ROM chip with a small window, that when illuminated with a special ultraviolet light cause the contents of the chip to be erased
Ultraviolet EPROM
Type of EPROM
ROM chip that uses eclectic voltages delivered to the pins of the chip to force contents to be erased
Electronically Erasable programmable read-only memory (EEPROM)
What is the difference between EEPROM vs Flash memory?
EEPROM must be fully erased to be rewritten
Flash memory can be erased and written in blocks or pages
SSDs do not overwrite blocks that contain data, what does it do?
It writes data to unused block and marks the previous block as unallocated
What are the two valid options for destroying data on SSD drives?
ATA Secure Erase
Destruction
Data destruction method
Writes over every character of data on a disk
Allows for media reuse
i.e. zeroing out
Clearing or Overwriting
Data destruction method
Repeats the clearing process multiple time and may combine it with other method
Purging
Data destruction method
Uses a strong magnetic field to destroy the integrity of the data on a hard drive
Degaussing
Data destruction method
Physically destroys the media device itself
i.e. incineration, shredding, acid chemicals, etc.
Destruction
Memory that loses its contents when system enters an unpowered state
Volatile memory
Memory retains it contents, even when there is no power to the system
Nonvolatile memory
Is the same as memory
Primary storage
Consists of magnetic, flash, and optical media that must be read into primary memory before the CPU can use the data
Secondary storage
Data that can be read at any point
Random Access storage devices
Requires scanning through all the data physically stored before the desired data location is brought up
Sequential access devices
What are the three main security issues surrounding secondary storage devices?
- Removable media can be used to steal data
- Access controls and encryptions must be applied to protect data
- Data can remain on the media even after file deletion of media formatting
What are some security risks posed that input/output devices can pose?
- Subject to eavesdropping and tapping
- Used to smuggle data out of an organization
- Can create insure point of entry into an organization’s system and networks
