Option field when IP packet has minimum size of 20 bytes?

Question

When the IP packet has minimum size (20bytes), what happens to option field. Is it not present or present with all bits set to 0 (all 40bytes of 0's)?

Comments

The bits of Options field are not present at all. A host identifies the presence of Options field from IHL(Internet Header Length) bits. If IHL is 5 (minimum header length), it will expect Payload exactly after 20 bytes of header. Refer RFC 791 for more detailed information.

Answer 1

          Option field in IP header is optional, i.e. if we look at IP packet of 20 bytes it wont be having any option field or data field .. 

Is it not present or present with all bits set to 0 (all 40bytes of 0's)?

           Even if you set all those option field bits to 0  ,it will consume the space . Hence it wont be having that 20bytes size. I guess it answer the second part.