Week 2 - Cryptography Aplications Flashcards
What is PKI (Public Key Infrastructure)?
a system that defines the creation, storage, and distribution of digital certificates
What is a digital signature?
a file that proves an entity owns a certain public key
What 3 things does a certificate contain?
- Info on Public Key
- Registered Owner
- Digital Signature
What does CA stand for?
Certificate Authority
What is a CA responsible for?
storing, issuing, and signing certificates
What does RA stand for?
Registration Authority
verifying the identities of any entities requesting certificates to be signed and stored with the CA (certificate authority)
What does CRL stand for?
Certificate revocation list
What does a CRL list provide?
a list of certificates that are no longer valid (certificate revocation list)
What does the X.509 standard define?
defines the format of digital certificates
What are the fields are defined in a X.509 standard?
defines the format of digital certificates
What are the fields are defined in a X.509 standard?
- Version
- Serial number
- Certificate signature algorithm
- Issuer name
- Validity
What are the 9 fields defined in a X.509 certificate?
- Version
- Serial number
- Certificate signature algorithm
- Issuer name
- Validity
- Subject
- Subject public key info
- Certificate signature algorithm
- Certificate signature value
What does CRL stand for?
Certificate Revocation List
What is a certificate revocation list (CRL)?
distributes a list of certificates that are no longer valid
What does the X.509 standard define?
defines the format of digital certificates
How does HTTPS protect us on the internet?
encapsulates the HTTP traffic over an encrypted secure channel using TLS or SSL
What does HTTPS stand for?
HyperText Transport Protocol (Secure)
What is HTTPS also called?
HTTP over SSL or TLS (what it uses to encapsulate traffic)
When was SSL 3.0 deprecated?
2015
What is TLS?
Provides a secure channel for an application to communicate with the service
(that’s independent of HTTPS but is used with it)
What are some examples that use TLS to secure communications? (4)
secure web browsing (HTTPS), email (SMTP/POP3 over TLS), online banking logins, and secure file transfers (FTPS) - any sensitive information
What is a session key?
a temporary, randomly generated cryptographic key used to encrypt and decrypt data during a single communication session
What is the session key derived from?
a master key using cryptographic algorithms
How do you defend against having your session key compromised?
use HTTPS across their entire website and strengthen session management
What does SSH stand for
Secure Shell
What is SSH?
a network protocol that allows users to securely communicate and share data between two computers over an unsecured network
What protocol is most commonly used for remote login to command-line-based system?
SSH (Secure Shell), which provides a secure way to access a remote computer’s shell and execute commands
What key does SSH use to authenticate the remote machine the client is connecting to?
the remote machine’s public key
What is PGP?
Pretty Good Privacy, a data encryption program that allows users to securely send and receive messages and files
What does PGP do?
encrypts and decrypts messages, authenticates messages with digital signatures, and encrypts files
What is PGP commonly used in?
Email encryption, File encryption, Digital signatures, Software signing
How secure is PGP?
extremely safe, if used correctly and securely - uses algorithms that are considered unbreakable
What does VPN stand for?
Virtual private network
What does a VPN allow you to do?
Hide your identity, Encrypt your data, Protect your privacy, Protect business communications, Avoid surveillance, Manage your online bank accounts
VPN is like an ____ ____ where…
encrypted tunnel” where your internet traffic is securely channeled through a remote server
What is a point-to-point VPN connection?
a secure connection between two devices or networks over the internet that encrypts data to prevent it from being intercepted
What does IPsec stand for?
Internet Protocol Security
What is IPsec?
a group of protocols that encrypts and authenticates IP packets to secure communications over networks
What 2 modes of operations does IPsec support?
transport mode and tunnel mode
How does IPsec work?
(the process, where is it sent)
creating a secure “tunnel” between two devices, encrypting data packets before sending them across a network
What’s the difference between transport mode and tunnel mode for IPsec?
Tunnel Mode provides end-to-end security by encrypting the entire IP packet, Transport Mode only encrypts the payload of the packet; Tunnel Mode is used for connecting entire networks, Transport Mode is used for host-to-host communication.
OpenVPN operates over either ____ or ____
UDP (User Datagram Protocol) or TCP (Transmission Control Protocol)
OpenVPN operates over port….?
UDP port 1194 by default, but can also use TCP port 443
Where is a Trusted Platform Module located?
on a computer’s motherboard as a separate chip, but it can also be built into the chipset
How does a TPM work?
A Trusted Platform Module (TPM) is a security chip that protects a computer or mobile device by storing and using cryptographic keys, and confirming the authenticity of the device’s software and firmware
What is remote attestation?
a security mechanism that allows a remote device to prove its identity and integrity to a remote party
What is data binding and sealing for TPM?
“data binding” refers to the process of encrypting data using a key generated by the TPM, essentially linking the data to that specific device, while “sealing” takes this a step further by only allowing decryption of the data if the system is in a specific configuration (like a certain set of platform measurements) at the time of decryption, effectively preventing access to the data if the system state has changed
What is a secure element?
a microprocessor chip that protects and stores sensitive data in a device
What is TEE?
Trusted Execution Environment (TEE) is a method of protecting sensitive data and operations in a device by isolating them in a secure area
TPMs are most commonly used to: (3)
to help protect encryption keys, user credentials, and other sensitive data.
What does FTE encrypt? [Full disk encryption]
all data on a disk drive, including the operating system, applications, and user data
