In an IPv4 datagram, the M bit is 0, the value of HLEN is

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In an IPv4 datagram, the M bit is 0, the value of HLEN is 10, the value of total length is 400 and the fragment offset value is 300. The position of the datagram, the sequence numbers of the first and the last bytes of the payload, respectively are

1. Last fragment, 2400 and 2789
2. First fragment, 2400 and 2759
3. Last fragment, 2400 and 2759
4. Middle fragment, 300 and 689

Correct Option: C

Since M bit is 0 there would be no fragment other than this fragment. Hence, this fragment is the "Last Fragment". HLEN defines the length of the Header in the Datagram. The value of HLEN is 10
∴ Size of the header is 10 * 4 = 40 B.
Length of Data = Total length – Header length = 400 – 40 = 360 B
The fragment offset of data in the original datagram is measured in units of 8 B. So to find first byte of

This fragment	First Byte	= Fragment offset.
	B

First Byte = 300 * 8 = 1 '2400' B. and hence the length of data is 360 B
So last byte on this datagram is 2759 i.e 2400 and 2759
Hence answer is (c) Last fragment, 2400 and 2759.