Mistake regarding protocol field example

[nocturne1]

In the 640-802 deluxe 5th edition, pages 85-86, it twice refers to TCP port 6 and UDP port 17 as hex. This is actually incorrect - they are decimal (although technically for TCP 6 hex and decimal are the same...).

Jay

[lammle]

The TCP 6 and UDP 17 are in hex, not decimal.
Here is a link of all the numbers used in that field:
http://www.iana.org/assignments/protocol-numbers
The RFC's list them as hex, as do my analyzers.
Cheers!
Todd

[nocturne1]

Yes, the analyzers show 0x11 for UDP, which is 17 decimal. And the IANA chart shows decimal for the leftmost column, which is 17. I guess it's just confusingly written when stating the protocol number is 17 (hex) - it leads one to interpret it that it's supposed to be 0x17, which is wrong....

[lammle]

I may need to rewrite that paragraph in the next update. Although, for the objectives, it is not important. However, I still want to be technically correct so I will think about how I want to approach this.
Thanks for the info!
Todd

[nocturne1]

One more thing regarding the same topic - I have not been able to find any other source than this book that refers to the protocol number in the IP header as a port. Is that a mistake? Or is there some other reference that confirms this?

[lammle]

I would call it a protocol number, not a port number. As I mentioned I will think about this paragraph in the in the next update.

It is not that important in regards to the CCNA objectives, but again, I will work on that paragraph when the time comes.

Thanks!
Todd

[nocturne1]

It's also mentioned as a port in the definition on the prior page. Thanks for the clarifications! :)

[Discover Cisco]

Thanks for posting this here Jay! Please do post any other errors you find in this book. I didn't find this in the Errata's list. I hope people continue to update the Errata list. (Don't want to be learning the wrong things)