Refer to the exhibit.
Host A pings interface S0/0 on router 3. What is the TTL value for that ping?
A. 252
B. 253
C. 254
D. 255
Correct Answer: B
Explanation/Reference:
From the CCNA ICND2 Exam book: "Routers decrement the TTL by 1 every time they forward a packet; if a router decrements the TTL to 0, it throws away the packet. This prevents packets from rotating forever." I want to make it clear that before the router forwards a packet, the TTL is still remain the same. For example in the topology above, pings to S0/1 and S0/0 of Router 2 have the same TTL. The picture below shows TTL values for each interf ace of each router and for Host B. Notice that Host A initializes ICMP packet with a TTL of 255:
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