Please help: ptp links addresses

> The usage is actually 75%, as there are effectively three addresses:
> the two ends (00 and 01) and the broadcast address for the network
> (11).  10 is the unused address.

You don't waste a broadcast address on a, let's say, /24 network but you
have to consider it as waste if you plan to use *a lot* of /30 networks.
Still, most of the routing protocols use broadcasting so I guess that's
what you meant when you said it wasn't a waste...

- Hugh