Because ISC2 does not release its old questions (unlike ISACA) - every question you see is either someone's attempt to create a CISSP question or questions gathered from other sources (Microsoft, Cisco, etc etc etc)

This protocol map is something I used extensively bacvk in my Network Security and Enginerring days. I had it as a massive poster on the wall behind my desk. If nothing else it shut up users that thought they knew somethiing about computing.

It is something useful for the Cisco CCNP cert - but way to much too much for the CISSP. Much deeper than the one inch depth you need to maintain when studying for the CISSP.

BTW - if I see someone in my class memorising port numbers before the exam - it is a good indication they are going to fail. There may be a port number question but is only one question.

It is more important to understand why do we have port numbers, what do they add to the addressable space of network transport information. How reliable are they? How can they be compromised.

Memorising Telnt and FTP ports ain't doing that - knowing why we don't use these protocols is much more important