Userland PPP/PPTP tunneling problem

Bill Fumerola billf at mu.org
Thu Apr 17 12:26:09 PDT 2003


On Thu, Apr 17, 2003 at 12:27:08PM -0600, Brett Glass wrote:
> At 12:18 PM 4/17/2003, Sten Daniel S?rsdal wrote:
> 
> >This is a known issue with the Microsoft PPTP client. It adds the natural
> >netmask and not the specified one. 
> 
> I don't understand. Why is /24 more "natural" than /16?

because that address is in class C space, not class B. read rfc791.

> >In case of 192.168.x.x/16 that is a 
> >255.255.255.0 netmask and with for example 80.80.80.0/24 is 80.0.0.0/8.
> 
> Even more confusion. How does it come up with that?

rfc791. specifically, because 192.168.x.x has the two highest bits set
(which makes it a class C address) and 80.80.80.0's highest bit is set
to 0 (which makes it a class A address). 

you're trying to apply rfc1518 and rfc1519 (cidr routing) and from what
Mr. Sørsdal is telling us, msft pptp just doesn't support that.

-- 
- bill fumerola / fumerola at yahoo-inc.com / billf at FreeBSD.org / billf at mu.org




More information about the freebsd-net mailing list