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I am capturing packets using libpcap. I am calculating the payload size as given here
size_payload = ntohs(ip->ip_len) - (size_ip + size_tcp);
Now when I print ntohs(ip->ip_len), I see that the value is 1280. For the same packets, wireshark shows a value of 1500 for the total length field in the IP header. Why do they differ?

asked 28 Sep '12, 01:59

rony358's gravatar image

accept rate: 0%

edited 28 Sep '12, 01:59

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question asked: 28 Sep '12, 01:59

question was seen: 6,274 times

last updated: 28 Sep '12, 01:59

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