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Cryptography - Coggle Diagram

- - - - The certificate revocation list is not current
    - - Two-factor authentication
    - - Unsuccessful logon attempts are actively monitored by the security administrator.
  - - - Presence of spyware in one of the ends
  - - - authenticity of the sender
- - - - An application layer security protocol developed by IETF to add confidentiality and authentication services to electronic message on the Internet
      - Provides end-to-end confidentiality, sender and forwarder authentication, originator non-repudiation, algorithm independence, Public Key Infrastructure X.509 support, X.500 distinguished name support
  - - - Developed by RSA Data Security, not an IETF
        standard
      - Gain wide acceptance since it work seamlessly with
        other MIME transports
      - 2 types of S/MIME messages
        
        Signed – provides integrity and sender authentication
        
        Signed & Enveloped – provides all 4 types of security
        functions
      - Features and formats are very similar to PEM
  - - - A secure message-oriented communication protocol designed to
        be used for securing message using the HTTP protocol
      - Preserves the characteristics of HTTP while allowing request and reply messages to be signed, authenticated, encrypted, or any combination of these
      - Multiple key-management mechanisms are supported
        
        Password-style manually shared secrets
        
        Public-key key exchange
      - Verify message integrity and sender authenticity using a Message Authentication Code, which is computed as a keyed hash over the document using a shared secret
      - Uses option negotiation to allow clients and servers to
        agree on:
        
        Transaction mode – signed or encrypted or both?
        
        Cryptographic algorithms – which for signing & encrypting?
        
        Certificate selection – which certificate should be used?
      - Limited uses but can meet very specific security needs
        
        e.g. Cryptographic security measures could be defined for individual Web pages such that individually encrypted Web pages could be published on any Web server but could only be read by those with authorized keys
  - - - An open protocol designed by Netscape for providing data encryption, server authentication, message integrity, and optional client authentication for a TCP/IP connection
      - Works in Transport layer and has 3 components: handshake, record, and alert protocols
  - - - A new protocol defined by IETF based on the SSL3.0
        protocol specification
      - There are significant differences between TLS 1.0 and
        SSL 3.0, mostly in the cryptographic algorithm they support, such that they do not necessarily interoperate
  - - - RFC 2401 – IP Security Architecture
        
        Defines the overall architecture and specifies elements common to both the IP Authentication Header (AH) and the IP Encapsulating Security Payload (ESP)
      - RFC 2402 – IP AH
        
        Defines an algorithm-independent mechanism for providing
        exportable cryptographic authentication without encryption to IPv4 and IPv6 packets
      - RFC 2406 – IP ESP
        
        Defines an algorithm-independent mechanism for providing
        encryption to IPv4 and IPv6 packets
      - RFC 2408 – Internet Security Association and Key
        Management Protocol (ISAKMP)
        
        Defines procedures and packet formats to establish, negotiate, modify and select Security Association (SA)
    - - A set of communication properties that provides a relationship between 2 or more system to build a unique connection
      - Defined by 3 components: Security Parameter Index (SPI), destination IP address, security protocol identifier
    - - IKE Security Association
        
        Duplex in nature such that a single SA can accommodate
        communications between 2 systems
      - Security Association Database (SAD)
        
        Contains all the data pertaining to each SA being used
      - Security Policy Database (SPD)
        
        Contains the policies that determine the character of the IP traffic
        coming into, or out of, the IP stack
        
        Uses selectors (destination IP address, source IP address, data sensitivity level, fully qualified name, upper layer protocol, upper layer protocol service ports) to map traffic to a policy, which ultimately maps to an SA that is maintained in the SAD
    - - Ensures the integrity and data origin authentication of the data, including the invariant fields in the outer IP header (no confidentiality protection)
      - Uses a keyed hash function rather than digital
        signatures for performance reasons
    - - When added to an IP packet, protects the confidentiality, integrity and data origin authentication of the data
      - If only the upper-layer data protocols must be authenticated, ESP authentication is an appropriate choice and is more space efficient then using AH to encapsulate ESP
    - - 2 hosts provide protection primarily for upper-layer protocols; the cryptographic endpoints are the source and destination of the data packet
    - - A vehicle for encapsulating packets inside a protocol that is understood at the entry and exit point of a given network as well as by intermediate security gateways
    - - The lowest level of management in which a person manually configures each system by keying material and SA management data relevant to secure communications with other systems
      - Appropriate when number of sites is small or all the site come
        under a single administrative domain
    - - 2 Phases of IKE
        
        Phase 2
        
        In Phase 2, SAs are negotiated on behalf of services
        such as IPSec AH or ESP
        
        IPSec uses a shared key, different from IKE, can be derived by using Diffie-Hellman again or by refreshing the shared secret derived from the original Diffie-Hellman exchanges that generated the IKE SA by hashing it with nonces
        
        Phase 1
        
        Main Mode for Phase 1 provide identity protection. When identity protection is not needed, Aggressive Mode can be used to further reduce round trips
        
        In Phase 1, the two ISAKMP peers establish a secure, authenticated channel (ISAKMP SA ) with which to communicate
        
        ISAKMP SA contains encryption algorithm, hash algorithm, authentication method, and information about a group on which to perform Diffie-Hellman
      - IKE Authentication Methods
        
        Preshared keys
        
        IKE peers authenticate each other by computing and sending a keyed hash of data that includes the preshared key
        
        Public key cryptography
        
        Each party generates a pseudo-random number (nonce) and encrypts it and its ID using the other party’s public key
        
        The ability for each party to compute a keyed hash containing the other’s nonce and ID, decrypted with the local private key, authenticates the parties to each other
        
        Digital signature
        
        Each device digitally signs a set of data and sends it to the other party
        
        Provides non-repudiation
      - Definitions
        
        A hybrid protocol combining parts of the following protocols to negotiate and derive keying material for SAs in a secure and authenticated manner (RFC 2409)
        
        ISAKMP which provides a framework for authentication and key exchange but does not define them. ISAKMP is designed to be key exchange independent
        
        Oakley which describes a series of key exchanges, called modes,
        and details the services provided by each
        
        SKEMI (Secure Key Exchange Mechanism for Internet) which describes a versatile key exchange technique that provides anonymity, reputability, and quick key refreshment
    - - Comprises a set of standards used to provide privacy
        and authentication services at the IP layer
      - Provides access control, connectionless integrity, data
        origin authentication, rejection of replayed packet, confidentiality, and limited traffic flow confidentiality
      - Can be used by higher layer protocols (such as TCP,
        UDP, ICMP, BGP,…)
  - - - Initially, the Kerberos client has an encryption key known only the user and the KDC. Similar, each application server shares an encryption key with the KDC.
    - - Kerberos Application Requests &
        Reply
    - - A secret-key network authentication protocol,
        developed at MIT, that uses AES for encryption and authentication (RFC 1510 – Kerberos v.5)
      - Based on the concept of a trusted 3rd party, Key
        Distribution Center (KDC), Kerberos is designed to authenticate user requests for network resources
      - To accomplish this, a trusted Kerberos server issue to
        user some “tickets”, which have limited lifespan and stored in the users’ credential cache and used in place of standard username and password scheme
- - - - is a type of symmetric encryption algorithm that can be designed to be exceptionally fast
    - - What encryption algorithm designed by the NSA uses an 80-bit key to encrypt 64-bit blocks of data?
    - - The encoding of information so that it cannot easily deciphered without the use of specialized decryption mechanisms or procedures
  - - - The transformation of encrypted information back to its original, nonencrypted form using special mechanisms or procedures
  - - - This is the message before anything has been done to it. It is either human-readable or in a format that anyone with the proper software can use
  - - - Text that is completely unreadable unless it has been turned back into readable form with the assistance of cryptographic decryption mechanisms
  - - - What algorithm uses an algebraic system defined on points, provides public-key algorithms and has the highest strength/bit of public key systems and is a big savings over other public key systems?
    - - The mathematical operations used to convert plaintext into ciphertext, and vice versa
  - - - A piece of information that must be known in order to
        encrypt or decrypt information
      - Introduces many flexibilities in enforcing disclosure protection and establishing distributed authentication
      - E(cleartext, key) = ciphertext
        D(ciphertext, key) = cleartext
- - - - A combination of encrypted content data (of any kind) and the content encryption key in an encrypted form that has been prepared for the use of the recipient is called?
  - - - What uses a combination of software, encryption technologies, and services that enables organizations to protect the security of their communications and business transactions on the Internet by the use of digital certificates to individual users and servers; end-user enrollment software; integration with corporate certificate directories; tools for managing, renewing, and revoking certificates; and related services and support?
    - - Directory Server
        
        Makes other users’ certificates available to applications
      - registration authority
        
        verifies information supplied by the subject requesting a digital certificate.
    - - relied upon to prove that an online transaction was authorized by a specific customer
    - - detailed descriptions for dealing with a compromised private key
  - - - The selection of the number that is going to be used to tailor
        an encryption mechanism to a particular use
      - Key be randomly chosen and not be disclosed at the time of selection, including information that is used in the key generation processes
    - - The process of getting a key from the point of its generation
        to the point of its intended use
      - Must be performed in a channel separate from the one that
        the traffic moves in
    - - The process of getting the key into the storage of the device
        or process that is going to use it
      - Minimize leakage of information about the key and error in
        its transcription
    - - Protect key by the integrity of the storage mechanism
      - Self-destruction when subject to forces or stored in encrypted
        form
    - - Re-generate key for uses periodically
    - - Key intended for encrypting keys cannot be used for data
    - - Disposed in such a way as to resist disclosure
- - - - Each step of the startup process contains components that are cryptographically signed by Apple
      - Boot ROM is laid down during
        chip fabrication
      - Use Apple Root CA public key to verify that the iBoot bootloader is signed by Apple
      - When the iBoot finishes its tasks,
        it verifies and runs the iOS kernel
- - - - What is a key clustering attack that happens when two different keys generate the same cipher text from the same plaintext?
      - Attacker can dramatically reduce the work factor to duplicate
        the hash by simple searching for these “birthday” pairs
    - - The systematic mathematical attempt to discover weakness in either cryptographic implementation or practices and to use these weaknesses to decrypt message
    - - Obtain an encryption device and deconstruct to learn how to extract plaintext
    - - Repeatedly trying different keys in order to obtain the plaintext
    - - The cryptanalyst is presented only with the unintelligible ciphertext, from which the cryptanalyst tries to extract the plaintext
    - - The cryptanalyst knows all or part of the contents of the ciphertext’s original plaintext, therefore, the work factor to extract the desired information from the ciphertext is significantly reduced
    - - The cryptanalyst can generate ciphertext from arbitrary
        plaintext, if the encryption algorithm is known
    - - Attempt to use the public key and factor the private key
    - - Attack intercepts an encrypted “secret” message and then
        simply send the message again
    - - Secure Socket Layer
      - By interjecting oneself into the path of secure communications or key exchange, the attack may be able to use the key or substitute its own key