From owner-freebsd-net@FreeBSD.ORG Thu Apr 17 04:57:21 2008 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 53178106564A for ; Thu, 17 Apr 2008 04:57:21 +0000 (UTC) (envelope-from kip.macy@gmail.com) Received: from wa-out-1112.google.com (wa-out-1112.google.com [209.85.146.181]) by mx1.freebsd.org (Postfix) with ESMTP id 24DA38FC17 for ; Thu, 17 Apr 2008 04:57:21 +0000 (UTC) (envelope-from kip.macy@gmail.com) Received: by wa-out-1112.google.com with SMTP id k17so4005568waf.3 for ; Wed, 16 Apr 2008 21:57:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; bh=kj0z5es3Wi4gu/K1/cGkDBWu7cKaGXdwTjgzjnDOTs4=; b=HdLp6AP/73FbQg/65duLmCjST6wQZR2PPxn5WpRJxizGHF/7LHieWLaOtBfaX+/6o6mwy3erXHhzcvXC55S52XRqD6YRhPltNwXkqjsqTlFR1FC1gsV+h24yMKCFd37/LuUfEd9MolZ8cJDGrXGE9e6+g0u/tMcTBdu0Rp74cXo= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=Pm7v9B3DcIWZWlQe3rmeJ4Bvz60WOfjOp7ehSHnE0lTES/C1UT+nFysnKiFjj39iAhLIzNimhN15yk8pnXH4xnHSzvzX3ox9/UpvHt94ue5jhC17WAYHbBm5F2ikZfg3y/KQOMn718I6tQNPpTmAqYrpyw6/EbxryYWNPuFpCJ4= Received: by 10.115.58.18 with SMTP id l18mr906313wak.177.1208408239971; Wed, 16 Apr 2008 21:57:19 -0700 (PDT) Received: by 10.114.255.16 with HTTP; Wed, 16 Apr 2008 21:57:19 -0700 (PDT) Message-ID: Date: Wed, 16 Apr 2008 21:57:19 -0700 From: "Kip Macy" To: "freebsd-net@freebsd.org" In-Reply-To: <20080417043131.GB1237@stlux503.dsto.defence.gov.au> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080417043131.GB1237@stlux503.dsto.defence.gov.au> Subject: Re: Planned contrib/rdma import X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Apr 2008 04:57:21 -0000 I received the following question in a private e-mail that I think others might be asking. > what is RDMA and ipwarp ? google didn't help much here :( RDMA in general is the ability to directly DMA to and from the memory of a remote host. In this particular context it is the ability to do so with authentication and access checking and thus does *not* cover firewire or countless other means by which one could trivially do memory to memory transfers. The two transports that allow this are infiniband and iwarp. Infiniband is a link layer transport. Iwarp uses TCP as the underlying transport. For more details you can see the RFCs and the consortium website. 4296 The Architecture of Direct Data Placement (DDP) and Remote Direct Memory Access (RDMA) on Internet Protocols. S. Bailey, T. Talpey. December 2005. (Format: TXT=43907 bytes) (Status: INFORMATIONAL) 4297 Remote Direct Memory Access (RDMA) over IP Problem Statement. A. Romanow, J. Mogul, T. Talpey, S. Bailey. December 2005. (Format: TXT=48514 bytes) (Status: INFORMATIONAL) 5040 A Remote Direct Memory Access Protocol Specification. R. Recio, B. Metzler, P. Culley, J. Hilland, D. Garcia. October 2007. (Format: TXT=142247 bytes) (Status: PROPOSED STANDARD) http://www.rdmaconsortium.org/home