WGU C191 Exam test preparation
Questions and Must have marking
scheme Updated version 2024/2025
disk block - correct answer a fixed sequence of bytes on the disk, which can only be
accessed as a single unit using low-level read-block and write-block operations
Magnetic hard disk - correct answer A magnetic disk is a storage device that uses a
magnetization process to write, rewrite and access data.
Magnetic Storage Devices - correct answer Includes magnetic tape, floppy disks and
hard-disk drives.
rotational latency - correct answer Rotational latency (in milliseconds) describes the
time required to position a specific sector under the read-write head. Average latency is
typically given as the time it takes the drive to perform half a rotation of the platter, and
is directly dependent on its RPM rating.
Partition - correct answer A logical division of a hard disk that is treated as a separate
unit by operating systems (OSes) and file systems
Trapdoor (aka Backdoor) - correct answer Mechanism that bypasses user
authentication. Ex: A systems programmer could modify the login utility to accept a
specific user without requiring a password, thus permitting unauthorized access to the
system at a later time
Buffer Overflow - correct answer An intrusion technique that exploits the fact that many
programs do not check for array overflow, allowing an attacker to overwrite portions of
memory beyond the legitimate scope of an input buffer.
login spoofing - correct answer Approach where a legitimate user presents a fake login
screen to an unsuspecting user, who unwittingly supplies a valid login name and
password to the imposter program. A possible solution to prevent login spoofing is to
,display the login screen only after the user has typed in a special character sequence
that automatically invokes the OS and which a user program cannot intercept (Ex:
CTRL-ALT-DEL).
logic bomb - correct answer Unauthorized code inserted into the system and executed
at a specified time to perform some destructive action. The main use of a logic bomb is
for blackmail or an act of revenge.
challenge response - correct answer a sort of public duel whereby one person offers a
word, gesture, question or action and the other must respond in a way that answers in
equal measure or ups the ante.
Advanced Encryption Standard (AES) - correct answer A symmetric cipher that was
approved by the NIST in late 2000 as a replacement for DES.
RSA Encryption - correct answer It is the most common internet encryption and
authentication system. The system used an algorithm that involves multiplying two large
prime numbers to generate a public key, used to encrypt data and decrypt an
authentication, and a private key, used to decrypt the data and encrypt an
authentication.
Asymmetric
Data Encryption Standard (DES) - correct answer A cipher (algorithm for doing
encryption and decryption) provided by the U.S. National Institute of Standards and
Technology (NIST).
Message Digests - correct answer The calculation resulting from a hash function.
Random Access Memory (RAM) - correct answer Computer location where
instructions and data are stored on a temporary basis. This memory is volatile,
rewritable. Can be called Main Memory
, What is a page frame? - correct answer It is a fixed-size contiguous block of physical
memory identified by a single number, the page frame number.
What is a page table? - correct answer It is an array that keeps track of which pages of
a given logical address space reside in which page frames. Each page table entry
corresponds to one page and contains the number or the starting address of the frame
containing the page.
What is a segment? - correct answer It is a space identified by a single number, the
segment number.
What is a segment table? - correct answer It is an array that keeps track of which
segment resides in which area of physical memory. Each entry corresponds to one
segment and contains the starting address of the segment.
Segmentation and paging - correct answer A process address space is broken into
VARIABLE sized blocks
A process address space is broken into FIXED sized blocks
Principle of locality - correct answer Locations accessed recently are more likely to be
accessed again than locations accessed in the distant past
What is a translation look aside buffer? - correct answer It is a fast and associative
It maintains recent translations of logical addresses to frames in physical memory for
faster retrieval.
Virtual Memory - correct answer It is a collection of one or more logical address
spaces, each of which may exceed the size of physical memory
Questions and Must have marking
scheme Updated version 2024/2025
disk block - correct answer a fixed sequence of bytes on the disk, which can only be
accessed as a single unit using low-level read-block and write-block operations
Magnetic hard disk - correct answer A magnetic disk is a storage device that uses a
magnetization process to write, rewrite and access data.
Magnetic Storage Devices - correct answer Includes magnetic tape, floppy disks and
hard-disk drives.
rotational latency - correct answer Rotational latency (in milliseconds) describes the
time required to position a specific sector under the read-write head. Average latency is
typically given as the time it takes the drive to perform half a rotation of the platter, and
is directly dependent on its RPM rating.
Partition - correct answer A logical division of a hard disk that is treated as a separate
unit by operating systems (OSes) and file systems
Trapdoor (aka Backdoor) - correct answer Mechanism that bypasses user
authentication. Ex: A systems programmer could modify the login utility to accept a
specific user without requiring a password, thus permitting unauthorized access to the
system at a later time
Buffer Overflow - correct answer An intrusion technique that exploits the fact that many
programs do not check for array overflow, allowing an attacker to overwrite portions of
memory beyond the legitimate scope of an input buffer.
login spoofing - correct answer Approach where a legitimate user presents a fake login
screen to an unsuspecting user, who unwittingly supplies a valid login name and
password to the imposter program. A possible solution to prevent login spoofing is to
,display the login screen only after the user has typed in a special character sequence
that automatically invokes the OS and which a user program cannot intercept (Ex:
CTRL-ALT-DEL).
logic bomb - correct answer Unauthorized code inserted into the system and executed
at a specified time to perform some destructive action. The main use of a logic bomb is
for blackmail or an act of revenge.
challenge response - correct answer a sort of public duel whereby one person offers a
word, gesture, question or action and the other must respond in a way that answers in
equal measure or ups the ante.
Advanced Encryption Standard (AES) - correct answer A symmetric cipher that was
approved by the NIST in late 2000 as a replacement for DES.
RSA Encryption - correct answer It is the most common internet encryption and
authentication system. The system used an algorithm that involves multiplying two large
prime numbers to generate a public key, used to encrypt data and decrypt an
authentication, and a private key, used to decrypt the data and encrypt an
authentication.
Asymmetric
Data Encryption Standard (DES) - correct answer A cipher (algorithm for doing
encryption and decryption) provided by the U.S. National Institute of Standards and
Technology (NIST).
Message Digests - correct answer The calculation resulting from a hash function.
Random Access Memory (RAM) - correct answer Computer location where
instructions and data are stored on a temporary basis. This memory is volatile,
rewritable. Can be called Main Memory
, What is a page frame? - correct answer It is a fixed-size contiguous block of physical
memory identified by a single number, the page frame number.
What is a page table? - correct answer It is an array that keeps track of which pages of
a given logical address space reside in which page frames. Each page table entry
corresponds to one page and contains the number or the starting address of the frame
containing the page.
What is a segment? - correct answer It is a space identified by a single number, the
segment number.
What is a segment table? - correct answer It is an array that keeps track of which
segment resides in which area of physical memory. Each entry corresponds to one
segment and contains the starting address of the segment.
Segmentation and paging - correct answer A process address space is broken into
VARIABLE sized blocks
A process address space is broken into FIXED sized blocks
Principle of locality - correct answer Locations accessed recently are more likely to be
accessed again than locations accessed in the distant past
What is a translation look aside buffer? - correct answer It is a fast and associative
It maintains recent translations of logical addresses to frames in physical memory for
faster retrieval.
Virtual Memory - correct answer It is a collection of one or more logical address
spaces, each of which may exceed the size of physical memory
