CREST CPSA PRACTICE EXAM TIPS QUESTIONS AND
ANSWERS GUARANTEE A+
✔✔What is ping sweep? - ✔✔Ping sweep is just a technique that can be used to find
out which hosts are alive in a network or large number of IP addresses.
✔✔Name Five Namp Flags. - ✔✔(TCP SYN scan, -sS)
(Null Scan, -sN)
(Ping Scan, -sP)
(Ack Scan, -sA)
(OS dect, -O)
✔✔What are the three firewall states? - ✔✔Open, Filtered Dropped Blocked, Closed not
listening.
✔✔What is TCP window size? - ✔✔Window size a method of controlling the flow of
packets between two computers or network hosts. Decieded in the tcp three way
handshake.
✔✔What is encoding? - ✔✔Encoding transforms data into another format using a
scheme that is publicly available so that it can easily be reversed.
✔✔What is encryption? - ✔✔scrambles information into an alternative form that requires
a key or password to decrypt the information back into its orginial form.
✔✔What is hashing - ✔✔Hashing serves the purpose of ensuring integrity, i.e. making it
so that if something is changed you can know that it's changed.
✔✔What is obfuscation? - ✔✔The purpose of obfuscation is to make something harder
to understand, usually for the purposes of making it more difficult to attack or to copy.
✔✔What is symmetric encryption? - ✔✔An encryption method in which the same key is
used to encrypt and decrypt the data.
✔✔What is asymmetric encryption? - ✔✔An encryption method in which two keys (one
private, one public) are used to encrypt and decrypt a message.
✔✔Vunerable hashing algorithms - ✔✔MD5, Sha-1, NTLM, LanMan.
✔✔Eny Symmertric algorithms. - ✔✔> DES
> 3DES (or Triple DES)
> RC4
> RC5
> AES (aka Rijndael)
, > Blowfish
> Serpent
> Twofish
> CAST5
> IDEA
✔✔Eny Asymmertric algorithms. - ✔✔> Elliptic curve
> RSA
> Diffie-Hellman
> DSA
> Key serialization
> ELGAMAL
✔✔What is a hash collision? - ✔✔A Hash Collision Attack is an attempt to find two input
strings of a hash function that produce the same hash result.
Because hash functions have infinite input length and a predefined output length, there
is inevitably going to be the possibility of two different inputs that produce the same
output hash.
✔✔What is Ipsec. - ✔✔Internet Protocol Security (IPsec) is a secure network protocol
suite that authenticates and encrypts the packets of data sent over an Internet Protocol
network.
✔✔What are two modes of operation for IPsec. - ✔✔Host-to-Host and Tunnelling mode.
✔✔What does IKE stand for? - ✔✔Internet Key Exchange
✔✔What does the linux file permission of 777 mean - ✔✔everyone(owner, group, users)
has read write and excuate of the file.
✔✔What is the definition of ACL? - ✔✔Access control list.
✔✔Common tool used on Microsoft operating system for managing process. - ✔✔Task
Manager.
✔✔Where is the SAM file located? - ✔✔C:\Windows\System32\drivers\etc\lmhosts.sam
✔✔What is an AS system. - ✔✔autonomous system
✔✔What is whois and what port ? - ✔✔a public Internet database that contains
information about Internet domain names and the people or organisations that
registered the domains. It is a source of information that can be used to exploit system
vulnerabilities. port 43.
ANSWERS GUARANTEE A+
✔✔What is ping sweep? - ✔✔Ping sweep is just a technique that can be used to find
out which hosts are alive in a network or large number of IP addresses.
✔✔Name Five Namp Flags. - ✔✔(TCP SYN scan, -sS)
(Null Scan, -sN)
(Ping Scan, -sP)
(Ack Scan, -sA)
(OS dect, -O)
✔✔What are the three firewall states? - ✔✔Open, Filtered Dropped Blocked, Closed not
listening.
✔✔What is TCP window size? - ✔✔Window size a method of controlling the flow of
packets between two computers or network hosts. Decieded in the tcp three way
handshake.
✔✔What is encoding? - ✔✔Encoding transforms data into another format using a
scheme that is publicly available so that it can easily be reversed.
✔✔What is encryption? - ✔✔scrambles information into an alternative form that requires
a key or password to decrypt the information back into its orginial form.
✔✔What is hashing - ✔✔Hashing serves the purpose of ensuring integrity, i.e. making it
so that if something is changed you can know that it's changed.
✔✔What is obfuscation? - ✔✔The purpose of obfuscation is to make something harder
to understand, usually for the purposes of making it more difficult to attack or to copy.
✔✔What is symmetric encryption? - ✔✔An encryption method in which the same key is
used to encrypt and decrypt the data.
✔✔What is asymmetric encryption? - ✔✔An encryption method in which two keys (one
private, one public) are used to encrypt and decrypt a message.
✔✔Vunerable hashing algorithms - ✔✔MD5, Sha-1, NTLM, LanMan.
✔✔Eny Symmertric algorithms. - ✔✔> DES
> 3DES (or Triple DES)
> RC4
> RC5
> AES (aka Rijndael)
, > Blowfish
> Serpent
> Twofish
> CAST5
> IDEA
✔✔Eny Asymmertric algorithms. - ✔✔> Elliptic curve
> RSA
> Diffie-Hellman
> DSA
> Key serialization
> ELGAMAL
✔✔What is a hash collision? - ✔✔A Hash Collision Attack is an attempt to find two input
strings of a hash function that produce the same hash result.
Because hash functions have infinite input length and a predefined output length, there
is inevitably going to be the possibility of two different inputs that produce the same
output hash.
✔✔What is Ipsec. - ✔✔Internet Protocol Security (IPsec) is a secure network protocol
suite that authenticates and encrypts the packets of data sent over an Internet Protocol
network.
✔✔What are two modes of operation for IPsec. - ✔✔Host-to-Host and Tunnelling mode.
✔✔What does IKE stand for? - ✔✔Internet Key Exchange
✔✔What does the linux file permission of 777 mean - ✔✔everyone(owner, group, users)
has read write and excuate of the file.
✔✔What is the definition of ACL? - ✔✔Access control list.
✔✔Common tool used on Microsoft operating system for managing process. - ✔✔Task
Manager.
✔✔Where is the SAM file located? - ✔✔C:\Windows\System32\drivers\etc\lmhosts.sam
✔✔What is an AS system. - ✔✔autonomous system
✔✔What is whois and what port ? - ✔✔a public Internet database that contains
information about Internet domain names and the people or organisations that
registered the domains. It is a source of information that can be used to exploit system
vulnerabilities. port 43.
