On Thu, 11 Dec 2003 19:55:41 -0500 "Theodore Ts'o" <[EMAIL PROTECTED]> wrote:
> On Thu, Dec 11, 2003 at 10:10:44PM +0100, Anthony G. Atkielski wrote: > > The dumb authors, I think, are those who built Linux implementations > > that doggedly attempt to negotiate ECN and are unprepared for cases > > where it does not work, even though it's unreasonable to assume that the > > entire world is equipped to handle ECN or that all other hosts will > > cheerfully ignore the setting of bits that are supposed to be zero. In > > this context, Linux is beginning to remind me of Netscape in the early > > days. > > What Linux implemented was specifically what was specified by RFC > 3168, no more no less. This RFC was in fact designed to deal with > hosts that were not equipped for ECN. The issue is whether or not > intermediate hosts are justified in dropping packets just because some > bits that were reserved for future use are no longer zero. I would > argue no. In summary, "Be liberal in what you accept, and conservative in what you send." ? Firewalls could be considered to be performing QA for defined protocol fields. I agree that reserved fields shouldn't be "QA"'ed for their default values. I can't remember exactly where I saw the definition, I've understood reserved fields to mean "could change in the future, don't rely on this default value". > > In fact, while many or most hosts do not support ECN, very few errant > firewalls and/or load balancing boxes were dropping packets that > support ECN. Firmware updates have been available for over two years > to fix those firewalls are broken, including no doubt the ones used by > ISOC. It's just that the ISOC firewall admins simply haven't had the > wit to upgrade their firewall firmware. Pretty much all of the > commercial websites were fixed a long, long, LONG time ago. > > - Ted This problem doesn't seem to be that uncommon, I can't seem to access one of the fathers of the Internet's home pages with ECN switched on either. Regards, Mark.
