Lecture 9 Flashcards
PKI & Cryptographic applications
What algorithm depends upon the computational complexity inherent in factoring large integer numbers?
RSA
_____ cryptography has a higher degree of computational requirements.
asymmetric
______ is the backbone of a large number of well-known security infrastructures
RSA
______ is based upon the computational complexity of factoring large integer numbers.
RSA
What is a super-increasing sequence?
Every element of a sequence is greater than the sum of all previous elements in the sequence.
________ depends on the ability to compute a point multiplication and the inability to compute the multiplicand given the original point and the product.
Elliptic Curve Cryptography
The problem of finding x, given P and Q is known as what?
elliptic curve discrete logarithm problem
A ______ takes a potentially long message and generates a unique output value.
Hash function
A sender generates a message digest. What must be true to verify that the message was not modified?
The recipient uses the same hash function to recompute the message digest and compare. If the 2 match the message was not altered.
What is true of a hash function?
A. Input can be any length B. output can be any length C. It is one-way D. Difficult to compute E. Output has a fixed length
A. Input can be any length
C. It is one-way
E. Output has a fixed length
_____ takes an input of any length and produces a 160-bit message digest. It processes a message in 512-bit blocks.
A. SHA-1
B. SHA-2
C. MD5
D. RSA
A. SHA-1
____ has 4 variants. It can produce a 224,256,512, or 382-bit message digest. The block size can be 512-bit bock or 1024-bit block.
A. SHA-1
B. SHA-2
C. MD5
D. RSA
B. SHA-2
Digital signatures provide for what? Select all that apply.
A. Delivery verification
B. Nonrepudiation
C. Protection again modification
B. Nonrepudiation
C. Protection again modification
NIST created ______ which specifies the approved digital signature algorithms.
Digital Signature Standard (DSS) FIPS 186-4
______ provides assurance that people are who they claim to be.
Digital Certificates
Certificates generally conform to the _____ standard.
A. X.500
B. X.510
C. X.509
D. X.515
C. X.509
____ are neutral organizations offering notarization services for digital certificates.
A. Certificate Authorities (CA)
B. Registration Authorities (RA)
C. Intermediate Authorities (IA)
A. Certificate Authorities (CA)
________ can be authorized to help verify identities before certificates are issued.
A. Certificate Authorities (CA)
B. Registration Authorities (RA)
C. Intermediate Authorities (IA)
B. Registration Authorities (RA)
What are at least 2 reasons a certificate may be revoked?
it was compromised
it was erroneously issued
details may have changed
security association changed (example: employee was fired)
The _____ or ______ checks for revoked certificates.
CRL (certificate revocation list)
OCSP (online certificate status protocol)
This is the ‘defacto’ standard as email encryption and uses RSA encryption and X.509 certificates for exchanging cryptographic keys.
Secure multipurpose internet mail extensions (S/MIME)
Websites can use which 2 technologies for secure communications?
A. HTTPS
B. SSL
C. S-HTTP
D. TLS
B. SSL
C. S-HTTP
____ uses port 443 to negotiate encrypted communications between web servers and clients. It keeps a channel open for the entire session.
HTTPS (uses SSL)
______ secures individual messages between a client and server and supports 2 way authentication between clients and servers.
S-HTTP
______ is the science of hiding messages in plain sight.
Steganography
_____ is a standard for protecting e-commerce transactions.
Secure Electronic Transaction (SET)
In ____ encryption, the entire communication is encrypted (data, header, trailer, address, etc.)
link
The standard architecture set by the IETF for setting up a secure channel between 2 parties. It uses public key cryptography.
IPSec (internet protocol security)
____ provides assurances of message integrity and nonrepudiation.
Authentication Header
IPSec has two modes.
Transport - packet payload is encrypted
Tunnel- entire packet, including header, is encrypted
Wireless encryption provides encryption from the client to the______.
wireless access point
