On Dec 15, 2010, at 10:22 AM, Christian Huitema wrote: > So I ran the program. With input "suppress = 0" I get: > outer->inner different: calculated: fd01:203:405:ffff:2:3:4:5 inner: > fd01:203:405:0:2:3:4:5 > and with "suppress = 0xFFFF" I get: > outer->inner different: calculated: fd01:203:405:0:2:3:4:5 inner: > fd01:203:405:ffff:2:3:4:5
Yes. I went through that in detail yesterday. On Dec 14, 2010, at 4:18 PM, Fred Baker wrote: > What the code is telling me is that 0xFFFF suppression is not necessary, but > having a subnet of one or the other representation of zero is a bad idea - > and which is a bad idea depends on whether I do or don't suppress 0xFFFF. > > [stealth-10-32-244-221:~] fred% a.out 0 > outer->inner different: fd01:203:405:ffff:2:3:4:5 vs fd01:203:405:0:2:3:4:5 > > If we turn suppression off, a subnet number of 0x0000 converts to 0xFFFF in > the destination address returning. It does this because it added the > adjustment in one direction and subtracted it in the other direction, and in > one's complement arithmetic, where x-x = x + (-x) = zero, it results in the > negative zero. > > [stealth-10-32-244-221:~] fred% a.out 1 > outer->inner different: fd01:203:405:0:2:3:4:5 vs fd01:203:405:ffff:2:3:4:5 > > If we turn suppression on, a subnet number of 0xFFFF converts to 0x0000 in > the destination address returning. > -----Original Message----- > From: Fred Baker [mailto:[email protected]] > Sent: Wednesday, December 15, 2010 9:47 AM > To: Christian Huitema > Cc: Rémi Després; Margaret Wasserman; NAT66 HappyFunBall > Subject: Re: [nat66] Constructive suggestions > > > On Dec 15, 2010, at 7:17 AM, Christian Huitema wrote: > >> Fred, >> >> Your program does not test for collision of the output, i.e. 2 inputs giving >> the same output. >> >> -- Christian Huitema > > Good catch. Thanks. See attached. > > The output is the same. > _______________________________________________ nat66 mailing list [email protected] https://www.ietf.org/mailman/listinfo/nat66
