From mboxrd@z Thu Jan 1 00:00:00 1970 From: "David S. Miller" Subject: Windows XP zero initial timestamps Date: Tue, 28 Oct 2003 00:58:42 -0800 Sender: netdev-bounce@oss.sgi.com Message-ID: <20031028005842.091c93a9.davem@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: kuznet@ms2.inr.ac.ru, b_wydrowski@yahoo.com.au, casey@carter.net, ccarter@cs.uiuc.edu Return-path: To: netdev@oss.sgi.com Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org This is for the people who brought up the zero timestamp issue with Windows XP. It may be allowed by RFC1323, but always using a zero initial timestamp breaks PAWS. PAWS depends upon each end-host using a single host-wide timestamp source for all connections. I can't even imagine what XP is trying to accomplish by using a zero-based timestamp for all connections. But there is no doubt that it breaks PAWS. The best we could ever do is to allow zero initial timestamps but to disable PAWS when using timestamps with such systems. Someone should contact the windows networking coders, I doubt they broke PAWS intentionally.