Question

In an IP packet, the value of HLEN is 5_16 and the value of the total length field is 0028_16. How many bytes of data are being carried by this packet?

(a) 10

(b) 40

(c) 60

(d) 20

The question was posed to me during an interview.

This key question is from IP Datagram Packet topic in division Internet Protocol, Network Addressing and Transport Level Security of Cryptograph & Network Security

Answer 1

Right option is (d) 20

To explain I would say: Total number of bytes in the header = 5 x 4 = 20 bytes.

Total length = 0028_16 = 40 bytes.

Data carried by the packet = (40 – 20) = 20 bytes.