From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?iso-8859-1?Q?Fran=E7ois-Xavier_Le_Bail?= Subject: Re: [PATCH net-next] IPv6: enable TCP to use an anycast address Date: Sat, 11 Jan 2014 05:06:10 -0800 (PST) Message-ID: <1389445570.24657.YahooMailBasic@web125502.mail.ne1.yahoo.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org, Hannes Frederic Sowa , "David S. Miller" , James Morris , Hideaki Yoshifuji , Patrick McHardy To: Alexey Kuznetsov Return-path: Received: from nm44.bullet.mail.ne1.yahoo.com ([98.138.120.51]:26475 "HELO nm44.bullet.mail.ne1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752343AbaAKNGX convert rfc822-to-8bit (ORCPT ); Sat, 11 Jan 2014 08:06:23 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Sat, 1/11/14, Alexey Kuznetsov wrote: > Hello! > I am just curious: since when is TCP allowed to use anycast addresses= ? As said in http://tools.ietf.org/html/draft-iab-anycast-arch-implicatio= ns-12.html#section-2.1 (this informational draft is in RCF queue) " No firm conclusion was reached regarding use of TCP with anycasted services, but it was observed that anycasting was useful for DNS, although it did introduce some new complexities." =46or this works, there is need for appropriate routing (BGP, ...). Many DNS root-servers use TCP with anycast (IPv4 and IPV6). see : http://tools.ietf.org/html/draft-jabley-dnsop-anycast-mapping-04#= section-4 " L-Root service is provided using a single IPv4 address (199.7.83.42= ) and a single IPv6 address (2001:500:3::42). It should be noted that it is preferable to refer to the service using its DNS name (L.ROOT- SERVERS.NET) rather than literal addresses, since addresses can change from time to time." =46ran=E7ois-Xavier Le Bail