Refer to the following command output on the router R3. Which of the following statements are correct?

display interface Tunnel

Tunnel0/0/0 current state : UP

Line protocol current state : UP

Last line protocol up time : 15:21:26 UTC-08:00

Description: HUAWEI, AR Series, Tunnel0/0/0 Interface

Route Port, The Maximum Transmit Unit is 1500

Internet Address is 20.1.1.2/24

Encapsulation is TUNNEL, loopback not set

Tunnel source 10.0.3.3 (LoopBack0), destination 10.0.1.1

Tunnel protocol/transport GRE/IP, key disabled

keepalive disabled

Checksumming of packets disabled