From owner-freebsd-net Wed Jun 21 19:25:50 2000 Delivered-To: freebsd-net@freebsd.org Received: from whizzo.transsys.com (whizzo.TransSys.COM [144.202.42.10]) by hub.freebsd.org (Postfix) with ESMTP id DE45137B774 for ; Wed, 21 Jun 2000 19:25:47 -0700 (PDT) (envelope-from louie@whizzo.transsys.com) Received: from whizzo.transsys.com (localhost.transsys.com [127.0.0.1]) by whizzo.transsys.com (8.9.3/8.9.1) with ESMTP id WAA35025; Wed, 21 Jun 2000 22:25:45 -0400 (EDT) (envelope-from louie@whizzo.transsys.com) Message-Id: <200006220225.WAA35025@whizzo.transsys.com> X-Mailer: exmh version 2.1.1 10/15/1999 To: "Anders Chr. Skoe" Cc: freebsd-net@FreeBSD.ORG, Julie Schlembach X-Image-URL: http://www.transsys.com/louie/images/louie-mail.jpg From: "Louis A. Mamakos" Subject: Re: Using timestamp option of ip header (IPOPT_TS) References: In-reply-to: Your message of "Wed, 21 Jun 2000 09:46:02 CDT." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 21 Jun 2000 22:25:45 -0400 Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org I don't think you want any IP options present at all. Depending on the specific implementations in routers, some (most?) will punt IP datagrams with options to a conventional CPU to process. As you only seem to care about timestamps as the packets are leaving the host, and as they arrive at the destination (I think?), there's an alternative approach you might consider. How about having a software shim, perhaps in the form of another network interface which encapsulates the packet to be sent inside another datagram which contains the timestamp the packet was sent (or at least queued for transmission). The remote host could then use the SO_TIMESTAMP socket option to cause a timestamp to be captured when the packet is received. (Though this only currently works for UDP sockets.) louie To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message