TLS Flashcards
Learn about what TLS is and how it works
What is TLS?
TLS is a widely adopted security protocol designed to facilitate privacy and data security for communications over the internet.
What does TLS achieve?
TLS achieves:
- Encryption: hides the data being transferred from third parties
- Authentication: ensures that the parties exchanging information are who they claim to be
- Integrity: verifies that the data has not been forged or tampered with
How is a TLS connection initiated?
A TLS connection is initiated using a TLS handshake.
What are the steps to a TLS handshake?
The steps to a TLS handshake are:
- Client hello
- Server generates master secret
- Server hello and finished
- Final steps and client finished
What is the client hello?
The client sends a hello message with the protocol version, the client random and a list of cipher suites, the client hello also includes the parameters that will be user for generating the master key.
What does it mean when the server generates the master secret?
It means that the server has received the client random and the clients parameters and cipher suite. It already has the server random since the server can generate that on its own. Therefore the server can create the master secret.
What is the server hello and finished?
The server hello includes the servers certificate, digital signature, server random and chosen cipher suite. Because it already has the master secter it also sends a finished message.
What are the final steps and client finished?
The client verifies the signature and certificate, generates master secret and sends the finished message.
What is a cipher suite?
A set of cryptographic algorithms used to secure network connections over TLS.
What is a pre-master secret?
A randomly generated secret generated by the client and used by the server to create the master secret.
What is the master secret?
The master secret is a function of the client and server randoms that were previously exchanged between the client and server during the handshake stage.
What is the pre-master secret?
The pre-master secret is a secret value generated by the client during the handshake, used to derive the master secret.
What is the master secret used for?
The master secret is used to generate the session key.
