access-control port bit masks - how do they work?

Hi,

 

Could someone please explain, in detail, how we define a port bit mask in an access-control.

In the net-net 4000 ACLI config documentation it states for a source and destination address...

 

<snip>

<IP address>[/number of address bits>][:<port>][/<port bits>]

 

For example:

10.0.0.1/24:5000/14

10.0.0.1/16

10.0.0.1/24:5000

10.0.0.1:5000

</snip>

 

IP address subnet masking is fairly straightforward and widely understood, but i have completely failed to find anyone who can explain how these port bits work.

 

Are there any guides available with good working examples?