Allocations for "always-on" ISPs

> NAT:ed addresses means that the customers' (private) address is not
> reachable from outside the point in which you do the NAT. This point
> resides within the primary (point of sale) operator's network.
> 
> Now, say that an ASP wants to offer some service to your customers
> (generating traffic = revenue) which has a communication pattern in which
> the ASP needs to connect to the customer's PC. Because of NAT, this is not
> possible.

Yes it is, you just have to put in the configuration.

> 
> A common application is remote access by IPSEC connections from
> mobile/residential users to the office. IPSEC+NAT is not a good
> combination. It has been known to work through NAT under some
> special circumstances, but typically gives you problems.

This is true.

> The fact is that the customers' addresses are not reachable from outside
> the NAT:ed area. This limits your ability to provide services to your
> customers.

Some services yes but not all.

> NAT may be used successfully in some scenarios, and unsuccessfully in
> others. In my opinion, it should be every operator's choice whether to
> deploy NAT, and not regulated by eg RIPE, and hence should not be
> considered as a solution for the "always-on" allocation problem.

I 100% agree.

Neil.