VPN GRE Tunnels

Question 1

For VPN tunnel configuration, where do the ‘source’ and ‘destination’ commands go?

Answer 1

On the tunnel interface.

Question 2

What kind of address does the source statement have?

Answer 2

• Either:
  
  • The public IP address of the outside interface or,
  • The interface identifier (s0/0/0)

Question 3

What kind of address does the destination statement have?

Answer 3

The public IP address of the remote router

Question 4

What is one additional but optional parameter for GRE tunnel configuration?

Answer 4

‘tunnel mode gre ip’

Question 5

What TCP/IP protocol number is GRE?

Answer 5

47

Question 6

What are the configuration commands that go on the tunnel interface?

Answer 6

• int tun0
  
  • ip address
  • tunnel mode gre ip
  • tunnel source s0/0/0
  • tunnel destination

Question 7

Name 3 show commands that can be used to verify a GRE tunnel configuration?

Answer 7

• sho ip int brief
• sho interface tun0
• sho ip route

Question 8

How is confidentiality maintained on a VPN tunnel?

Answer 8

Encryption

Question 9

How is data integrity maintained on a VPN tunnel?

Answer 9

Hashing