Consider an IPv4 packet p with source address 11.125.216.2 and desti- nation address 8.8.8.8, with the...

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Consider an IPv4 packet p with source address 11.125.216.2 and desti- nation address 8.8.8.8, with the ICMP Echo Request payload. A router in the path with IP address 173.11.82.118 receives this packet and attempts a nonlocal packet forwarding on the packet. Assume that the router has the following forwarding table Destination Next Hop 173.12.0.0/16 173.12.82.1 26.72.162.0/24 4.2.1.16 8.8.9.0/24 115.238.66.2 (a) What are the source and destination IP addresses on the packet that the router transmits upon receiving p? Let's call this packetp/. (b) What is the ICMP message type and code in p/? (e) Is this ICMP message a status reporting message, or an error reporting one? (d) Does / include sections of another ICMP message, as well? (Yes/No) If so, what is type of that ICMP message? If not, explain the reason. Consider the network in Figure 2. Assume that A sends an IPv4 packet to B. In each of the following cases, specify who can potentially be the source of the ICMP message, reporting an error to A. (a) ICMP Destination Unreachable: Network Unreachable (b) ICMP Destination Unreachable: Host Unreachable (c) ICMP Destination Unreachable: Port Unreachable (d) ICMP Redirect Message (e) ICMP TTL expired Consider an IPv4 packet p with source address 11.125.216.2 and desti- nation address 8.8.8.8, with the ICMP Echo Request payload. A router in the path with IP address 173.11.82.118 receives this packet and attempts a nonlocal packet forwarding on the packet. Assume that the router has the following forwarding table Destination Next Hop 173.12.0.0/16 173.12.82.1 26.72.162.0/24 4.2.1.16 8.8.9.0/24 115.238.66.2 (a) What are the source and destination IP addresses on the packet that the router transmits upon receiving p? Let's call this packetp/. (b) What is the ICMP message type and code in p/? (e) Is this ICMP message a status reporting message, or an error reporting one? (d) Does / include sections of another ICMP message, as well? (Yes/No) If so, what is type of that ICMP message? If not, explain the reason. Consider the network in Figure 2. Assume that A sends an IPv4 packet to B. In each of the following cases, specify who can potentially be the source of the ICMP message, reporting an error to A. (a) ICMP Destination Unreachable: Network Unreachable (b) ICMP Destination Unreachable: Host Unreachable (c) ICMP Destination Unreachable: Port Unreachable (d) ICMP Redirect Message (e) ICMP TTL expired