Communication Security

Question 1

What is TLS?

Answer 1

• TLS ensures integrity of transferred data.
• The session key is created from random numbers that are exchangeable during the TLS handshake.
• The algorithms used inside a session are negotiated between client and server.
• The subject of the server certificate must be equal to the servers host name entered in the browser.

Question 2

Which TCP port is reserved for HTTP over TLS?

Answer 2

Port 443

Question 3

TOR networks

Answer 3

Each node in the network knows the previous and next node along a connection but no other peers.

Question 4

HTTPS

Answer 4

Hyper Text Transfer Protocol Secure
A extension of HTTP; port 80
HTTPS; port 443

Question 5

X.509

Answer 5

Is a type of certificate for HTTPS, to authenticate the server (and sometimes the client).

As consequence authorities are necessary to verify the relation between the certificate and it’s owner.

(Certificate authorities can be a potential weak point, allowing for middle man attacks)