A host with an IP address, 10.10.10.6/29, sends ICMP control messages of Echo Request to 10.10.10.7/29 but receives no response because requests timed out. Which of the following is the most likely cause?
A. The destination ignores the requests, or the network is jammed.
B. The default gateway of the host is not properly configured.
C. The routing table of the gateway doesn’t converge.
D. The destination resides in another broadcast domain.
Kindly be reminded that the suggested answer is for your reference only. It doesn’t matter whether you have the right or wrong answer. What really matters is your reasoning process and justifications.
My suggested answer is A. The destination ignores the requests, or the network is jammed.
10.10.10.0/29 => the subnet
10.10.10.6/29 => the host
10.10.10.7/29 => broadcast
Host:>ping -b 10.10.10.7
Nowadays, most machines ignore broadcasted ICMP requests. However, some machines may still opt to respond to broadcasted ICMP Echo Requests. In this situation, only if the network is jammed, the host won’t receive ICMP Echo Reply.
10.10.10.7/29 is the broadcast address of the subnet. Addresses, 10.10.10.6/29 and 10.10.10.7/29, are on the same subnet. The host won’t send the ICMP Echo Request (10.10.10.7/29) to the default gateway (router). In other words, it doesn’t matter how the default gateway on the host is configured. The routing table of the gateway is irrelevant.
Since 10.10.10.7/29 is the broadcast address, there is no concern for multiple broadcast domains.
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