21-3PING 1.1.2.2: 56 data bytes, press CTRL_C to breakReply from 1.1.2.2: bytes=56 Sequence=1 ttl=254 time=53 msRecord Route:1.1.2.11.1.2.21.1.1.21.1.1.1Reply from 1.1.2.2: bytes=56 Sequence=2 ttl=254 time=1 msRecord Route:1.1.2.11.1.2.21.1.1.21.1.1.1Reply from 1.1.2.2: bytes=56 Sequence=3 ttl=254 time=1 msRecord Route:1.1.2.11.1.2.21.1.1.21.1.1.1Reply from 1.1.2.2: bytes=56 Sequence=4 ttl=254 time=1 msRecord Route:1.1.2.11.1.2.21.1.1.21.1.1.1Reply from 1.1.2.2: bytes=56 Sequence=5 ttl=254 time=1 msRecord Route:1.1.2.11.1.2.21.1.1.21.1.1.1--- 1.1.2.2 ping statistics ---5 packet(s) transmitted5 packet(s) received0.00% packet lossround-trip min/avg/max = 1/11/53 msThe principle of ping –r is as shown in Figure 21-1.1) The source (Device A) sends an ICMP echo request with the RR option being empty to thedestination (Device C).2) The intermediate device (Device B) adds the IP address (1.1.2.1) of its outbound interface to theRR option of the ICMP echo request, and forwards the packet.3) Upon receiving the request, the destination device copies the RR option in the request and addsthe IP address (1.1.2.2) of its outbound interface to the RR option. Then the destination devicesends an ICMP echo reply.4) The intermediate device adds the IP address (1.1.1.2) of its outbound interface to the RR option inthe ICMP echo reply, and then forwards the reply.
