Question from my new Cisco Press CCNA book

polm

Which of the following are not fields in an IP packet ? (Choose three.)

A. Flags

B. Length

C. Protocol

D. Source Address

E. Header Checksum


Now I was thinking that maybe they were trying to point out some differences in Packet vs. Header... but I just cant figure this one out.

The 20 byte IP header contains ALL of those feilds. What would the "packet" fields be ?

http://www.erg.abdn.ac.uk/user...t-pages/ip-packet.html <---IP Header

wildfire

Thats a strange one indeed! they are all field in an IP packet, RFC 791 refers to this

http://www.netfor2.com/rfc791.txt

Alien

polm

According to the CiscoPress Book. The Answer:

A. Flags

C. Protocol

E. Header Checksum

I really don't think this question is valid.

polm

TCP Header : http://www.freesoft.org/CIE/Course/Section4/8.htm

Does NOT have : Flags, Length, Protocol, or Source Address. It DOES have a Checksum (combination of Header and Data)

UDP Header : http://www.erg.abdn.ac.uk/user...se/inet-pages/udp.html

Does NOT have : ALL of them.

So the author probably didnt mean to say TCP or UDP instead of IP.

Must have something to do with the word "Packet".

Any thoughts ?

polm

It can't be packet vs. header. Packet has a header.

http://en.wikipedia.org/wiki/Packet

Time to send the Author of this book ,Steve McQuerry, an email.