On 2014-03-02, Paul B. Henson <hen...@acm.org> wrote: > On Sat, Mar 01, 2014 at 12:56:16PM +0900, YASUOKA Masahiko wrote: > >> As the default, npppd doesn't use the local tunnel endpoint address >> and broadcast addresses in class network (10.0.0.0 and 10.255.255.255) >> for the clients. Do you worry about 10.128.120.0 or 10.128.120.255 in >> this case? > > Technically, given they are all /32 point to point links, you could actually > make the local side .0 and use everything up to .255 (I think), but > I'm ok with losing two addresses to conform to usual /24 semantics and > less risk of confusion at some point. Setting the pppx IP to 10.128.120.1 > and the ipcp pool to 10.128.120.0/24 will work perfectly for me, thanks > much for the help.
There was some interesting research done into this using RIPE's probe network https://labs.ripe.net/Members/stephane_bortzmeyer/all-ip-addresses-are-equal-dot-zero-addresses-are-less-equal Avoiding these addresses seems a sane default, however people with a serious shortage of routable IPv4 addresses and no OS problems may want to use them anyway, so it might be a useful thing to be able to configure.
