VPN Protocols

Question 1

What can we use to create a secure connection between two or more computers/devices, that are not on the same private network?

Answer 1

VPN

Question 2

What are the 3 major VPN’s?

Answer 2

PPTP (Point to Point Tunneling Protocol)
LT2P (Layer 2 Tunneling Protocol)
IPSec

Question 3

What protocol encapsulates PPP packets and ultimately sends data as encrypted traffic?

What port does PPTP use?

Answer 3

PPTP (Point to Point Tunneling Protocol)

Port 1723

Note: PPP = Point to Point Protocol.

Question 4

What type of authentication does PPTP use?

Answer 4

CHAP authentication.

Note: This makes PPTP vulnerable to attacks. If you use PPTP, you must use a stronger method of authentication or use another VPN type.

Question 5

What VPN protocol does not provide any level of security on its own?

What port does L2TP use?

Answer 5

LT2P (Layer 2 Tunneling Protocol)

Port 1701

Note: LT2P is generally paired with IPSec to provide security.

Question 6

What TCP/IP protocol do we use to authenticate and encrypt IP packets to secure communication between devices?

Answer 6

IPSec

Note: IPSec is used heavily for VPN’s

Question 7

What method does IPSec use to create a secure tunnel?

Answer 7

Internet Key Exchange

Question 8

What do you call the establishment of secure connections and shared security information using certificates or cryptographic keys?

Answer 8

Security Association (SA)

Note: Need to remember for the exam.

Definition: The establishment of secure connections and shared security information using certificates or cryptographic keys

Question 9

What protocol in IPSec provides integrity and authentication?

Answer 9

Authentication Header

Note: The AH is hashed to provide integrity. It is often used with an Encapsulating Security Payload (ESP)

Question 10

What provides integrity, confidentiality, and authenticity of packets by encapsulating and encrypting them?

Answer 10

Encapsulating Security Payload

Question 11

What are the two modes of IPSec?

Answer 11

Transport Mode and Tunnel Mode

Question 12

Explain Transport mode and when its used.

Answer 12

Transport mode is host-to-host and only encrypts the payload. This means the to and from address is visible to anyone. Because of this, it should only be used within a private network.

Question 13

Explain Tunnel mode and when it’s used.

Answer 13

Tunnel mode encrypts both the header and the payload.

Note: Imagine that you can not see the truck driver, or what is being delivered. Tunnel mode is commonly used between networks over the internet. Used a lot in VPN’s.