Re: [shara] [BEHAVE]TR: I-DAction:draft-boucadair-pppext-portrange-option-00.txt

[<[e-mail]>]

 

> De la part de Dan Wing
> > 
> > Thank you for your comment.
> > 
> > There is a subtlety between subnet mask and port mask: 
> > subnets need to be hierarchical but not port ranges!
> 
> I disagree.  Port ranges all belong to the same IP address -- 
> from the view of the rest of the Internet.  This is akin to the 
> rest of the Internet's view of a subnet.  It is only the local
> IP address (subnet) that is aware of the separation of ports
> (or IP addresses) to individual hosts.
> 

I see your point. What we had in mind is different; when we say subnets
are hierarchical we mean a subnet can be in a bigger subnet which can be
in a bigger subnet, and so forth (within the limit of the 32 bits!).
There are some cases where this scheme can apply to port ranges, when
several A+P devices are cascaded, as a CPE and its hosts. But in a
configuration where only CPEs are Port Range-enabled there is no
hierarchy from this standpoint.

Another difference with subnets is if subnet bits are not contiguous,
the bits in between do exist in the address, are completely part of the
address, and refer, as a whole, to the host id. If Port Range bits are
not contiguous, there are no other significant bits melt with that have
a separate meaning.

What I'm trying to say is, it is not because non contiguous bits are a
bad thing for subnets that they are automatically bad for Port Ranges.


Regards,

Pierre