Exan$$ple $19\mathrm{.}2$

In an IPv$4$ packet, the value of HLEN is $(1000{)}_2.$ How many bytes of options are being carried by this packet?

Solution

The HLEN value is $8,$ which means the total number of bytes in the header is $84,$ or $32$ bytes.

The first $20$ bytes are the base header, the next $12$ bytes are the options.