Secure Communications Protocol

Question 1

IPsec - What is Public Key Cryptopgraphy used for?

Answer 1

Encryption, Access Control, Non Repudiation, message authentication

Question 2

IPsec - What is the primary use of IPsec

Answer 2

VPN

Question 3

IPsec - In which modes can IPsec operate?

Answer 3

Transport or tunnel mode

Question 4

Kerberos - What solution does it offer?

Answer 4

Single Sign On (SSO)

Question 5

Kerberos - What is protected?

Answer 5

Logon credentials

Question 6

What do modern implementations of Kerberos use?

Answer 6

Hybrid encryption to provide reliable authentication protection

Question 7

What kind of technique/encryption is SSH?

Answer 7

End to end encryption technique

Question 8

What is SSH used for?

Answer 8

encryption of plaintext (rcp, rlogin, rexec);
protocol encryption (such as with SFTP);
VPN

Question 9

What does Signal protocol provide?

Answer 9

End to end encryption for voice communication, videoconferencing, text message services

Question 10

What is S-RPC (Secure Remote Procedure Call) and what is it used for?

Answer 10

authentication service;

prevention of unauthorized execution of code on remote systems

Question 11

What is SSL (Secure Sockets Layer) and what is it used for?

Answer 11

encryption protocol developed by Netscape;

to protect communications between web server and web browser

Question 12

What kind of traffic can be secured by SSL?

Answer 12

web, email, File transfer protocol (FTP), telnet

Question 13

SSL is a “….”-oriented protocol

Answer 13

session-oriented

Question 14

What does SSL provide related to CIA?

Answer 14

confidentiality + integrity

Question 15

SSL Key size

Answer 15

40 bits or 128 bits

Question 16

SSL is superseded by “…”

Answer 16

Transport Layer Security (TLS)

Question 17

Advantage of using TLS instead of SSL

Answer 17

stronger authentication and encryption protocols

Question 18

SSL/TLS protects against which type of attacks?

Answer 18

tampering, spoofing, eavesdropping

Question 19

Features of SSL/TLS

Answer 19

• secure client server communication in insecure network
• one way authentication
• two way authentication (digital certs)
• initial payload of TCP package –> encapsulation of all higher layer protocol payloads
• can be implemented at lower layers to operate as VPN (OpenVPN)
• can be used to encrypt UDP + SIP connections; SIP = protocol for VoIP