4.2 Decreased Risks   The increase in number of physical servers reduces the likelihood   that a denial-of-service attack will take out a significant portion   of the DNS infrastructure.  The increase in servers also reduces the   effect of machine crashes, fiber cuts, and localized disasters by   reducing the number of users dependent on a specific machine.5. Acknowledgments   Masataka Ohta, Bill Manning, Randy Bush, Chris Yarnell, Ray Plzak,   Mark Andrews, Robert Elz, Geoff Huston, Bill Norton, Akira Kato,   Suzanne Woolf, Bernard Aboba, Casey Ajalat, and Gunnar Lindberg all   provided input and commentary on this work.  The editor wishes to   remember in particular the contribution of the late Scott Tucker,   whose extensive systems experience and plain common sense both   contributed greatly to the editor's own deployment experience and are   missed by all who knew him.Hardie                       Informational                      [Page 6]RFC 3258        Distributing Authoritative Name Servers       April 20026. References   [SECONDARY] Elz, R., Bush, R., Bradner, S. and M. Patton, "Selection               and Operation of Secondary DNS Servers", BCP 16, RFC               2182, July 1997.   [ROOT]      Bush, R., Karrenberg, D., Kosters, M. and R. Plzak, "Root               Name Server Operational Requirements", BCP 40, RFC 2870,               June 2000.   [ANYCAST]   Patridge, C., Mendez, T. and W. Milliken, "Host               Anycasting Service", RFC 1546, November 1993.Hardie                       Informational                      [Page 7]RFC 3258        Distributing Authoritative Name Servers       April 2002Appendix A.       __________________Peer 1-|                |Peer 2-|                |Peer 3-|     Switch     |Transit|                |  _________                   _________etc    |                |--|Router1|---|----|----------|Router2|---WAN-|       |                |  ---------   |    |          ---------       |       |                |              |    |                          |       |                |              |    |                          |       ------------------            [NTP] [DNS]                       |                                                                       |                                                                       |                                                                       |                                                                       |       __________________                                              |Peer 1-|                |                                              |Peer 2-|                |                                              |Peer 3-|     Switch     |                                              |Transit|                |  _________                   _________       |etc    |                |--|Router3|---|----|----------|Router4|---WAN-|       |                |  ---------   |    |          ---------       |       |                |              |    |                          |       |                |              |    |                          |       ------------------            [NTP] [DNS]                       |                                                                       |                                                                       |                                                                       |                                                                       |       __________________                                              |Peer 1-|                |                                              |Peer 2-|                |                                              |Peer 3-|     Switch     |                                              |Transit|                |  _________                   _________       |etc    |                |--|Router5|---|----|----------|Router6|---WAN-|       |                |  ---------   |    |          ---------       |       |                |              |    |                          |       |                |              |    |                          |       ------------------            [NTP] [DNS]                       |                                                                       |                                                                       |                                                                       |Hardie                       Informational                      [Page 8]RFC 3258        Distributing Authoritative Name Servers       April 2002                                                                       |       __________________                                              |Peer 1-|                |                                              |Peer 2-|                |                                              |Peer 3-|     Switch     |                                              |Transit|                |  _________                   _________       |etc    |                |--|Router7|---|----|----------|Router8|---WAN-|       |                |  ---------   |    |          ---------       |                |              |    |       |                |              |    |       ------------------            [NTP] [DNS]Hardie                       Informational                      [Page 9]RFC 3258        Distributing Authoritative Name Servers       April 20027. Editor's Address   Ted Hardie   Nominum, Inc.   2385 Bay Road.   Redwood City, CA 94063   Phone: 1.650.381.6226   EMail: Ted.Hardie@nominum.comHardie                       Informational                     [Page 10]RFC 3258        Distributing Authoritative Name Servers       April 20028.  Full Copyright Statement   Copyright (C) The Internet Society (2002).  All Rights Reserved.   This document and translations of it may be copied and furnished to   others, and derivative works that comment on or otherwise explain it   or assist in its implementation may be prepared, copied, published   and distributed, in whole or in part, without restriction of any   kind, provided that the above copyright notice and this paragraph are   included on all such copies and derivative works.  However, this   document itself may not be modified in any way, such as by removing   the copyright notice or references to the Internet Society or other   Internet organizations, except as needed for the purpose of   developing Internet standards in which case the procedures for   copyrights defined in the Internet Standards process must be   followed, or as required to translate it into languages other than   English.   The limited permissions granted above are perpetual and will not be   revoked by the Internet Society or its successors or assigns.   This document and the information contained herein is provided on an   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.Acknowledgement   Funding for the RFC Editor function is currently provided by the   Internet Society.Hardie                       Informational                     [Page 11]