Needs Improvement Flashcards
DES
Symmetric
Key Length: 64 bit
3 DES or
TDES
(Triple DES)
Symmetric
Key Length 56 bit*3
AES
Symmetric
Key Length: 128,192,256 bit
IDEA
Symmetric
128 bit
Skipjack
Symmetric
80 bit
Blowfish
Symmetric
32-448 bit
TwoFish
Symmetric
2048
RC4
Symmetric
40-2048
RC5
Symmetric
2048
CAST
Symmetric
40-128 bit & 128-256 bit
Diffie Hellman
Asymmetric
No confidentiality, authentication, or
non-repudiation
* Secure key transfer
RSA
Asymmetric
4096 bit
Uses 1024 keys
* Public key and one-way function for
encryption and digital signature
verification
* Private key and one-way function for
decryption and digital signature
generation
* Used for encr
Elgamal
Asymmetric
Any Size
Elliptic Curve Cryptosystem (ECC)
Asymmetric
Any Size
Symmetric Algorithms
Use a private key which is a secret key between two parties.
Each party needs a unique and separate private key.
Number of keys = x(x-1)/2 where x is the number of users. Eg.
DES, AES, IDEA, Skipjack, Blowfish, Twofish, RC4/5/6, and
CAST.
Stream Based Symmetric Cipher
Encryption done bitwise and use keystream generators Eg.
RC4.
Block Symmetric Cipher
Encryption done by dividing the message into fixed-length
blocks Eg. IDEA, Blowfish and, RC5/6
Asymmetric Algorithms
Use public and private key where both parties know the public
and the private key known by the owner .Public key encrypts
the message, and private key decrypts the message. 2x is total
number of keys where x is number of users. Eg. Diffie-Hellman,
RSA, El Gamal, ECC, Knapsack, DSA, and Zero Knowledge
Proof.
Physical (1)
Electrical signal : Bits to voltage
Data Link Layer (2)
PPP - PPTP - L2TP - - ARP -
RARP - SNAP - CHAP - LCP -
MLP - Frame Relay - HDLC -
ISL - MAC - Ethernet - Token
Ring - FDDI
Network
layer (3)
CMP - BGP - OSPF - RIP - IP -
BOOTP - DHCP - ICMP
Transport (4)
TCP - UDP datagrams. Reliable end to end data
transfer -Segmentation - sequencing - and error checking
Session (5)
TCP - UDP - NSF - SQL - RADIUS - and RPC - PPTP - PPP
Presentation (6)
TCP - UDP messages
Application (7)
TCP - UDP - FTP - TELNET -
TFTP - SMTP - HTTP CDP -
SMB - SNMP - NNTP - SSL -
HTTP/HTTPS.
Challenge-Handshake Authentication Protocol (CHAP)
Encrypt username/password and
re-authenticate periodically. Use in PPP.
Point-to-Point Tunneling Protocol
(PPTP)
- PPP for authentication
- No support for EAP
- Dial in
- Connection setup uses plaintext
- Data link layer
- Single connection per session
Layer 2 Tunneling Protocol (L2TP)
- Same as PPTP except more secure
- Commonly uses IPsec to secure L2TP packets
Internet Protocol Security (IPsec)
- Network layer
- Multiple connection per session
- Encryption and authentication
- Confidentiality and integrity
EAP (Extensible
Authentication Protocol)
Utilizes PPP and wireless authentication. Compatible with
other encryption technologies
Discretionary Access Control
(DAC)
Uses access control lists (ACLs -
Access-control lists).
Mandatory Access Control
(MAC)
Subject authorize according to security labels.
Used by owners to grant or deny access to
other users. ACL defines the level of access
granted or denied to subjects.
Role-BAC (RBAC)
Task-based access controls - subjects require
access an object based on its role or
assigned tasks.
Rule-BAC
Uses a set of rules or filters to define what
can or cannot be done on a system.
Lattice based / Label
Objects are classified based on control level
using a label.
Non-discretionary access /
Mandatory-Access control
Based on policies defined by a central
authority. Role based or task based.
Kerberos
Client /server model authentication protocol.
* Symmetric Key Cryptography
* Key Distribution Center (KDC)
* Confidentiality and integrity and authentication,
symmetric key cryptography
The Kerberos
logon process
- User input username/password in client PC/Device.
- Client system encrypts credentials using AES to submit
for KDC. - KDC match input credentials against database.
- KDC create a symmetric key and time-stamped TGT to be
used by the client and the Kerberos server. - Key and TGT are encrypted using client password hash.
- Client installs the TGT and decrypts the symmetric key
using a hash.
Risk Management
the process of identifying,
examining, measuring, mitigating, or transferring
risk
Preventative Risk Management
Security Policies
Security Cameras
Callback
Security Awareness Training
Job Rotation
Encryption
Data Classification
Smart Cards
Deterrent Risk Management
Security Personnel
Guards
Security Cameras
Separation of Duties
Intrusion Alarms
Awareness Training
Firewalls
Encryption
Detective Risk Management
Logs
Security Cameras
IDS
Honey Pots
Audit Trails
Mandatory Vacations