IPv6 Router Advertisement Option for DNS Configuration
RFC 5006
Document | Type |
RFC - Experimental
(September 2007; No errata)
Obsoleted by RFC 6106
Was draft-jeong-dnsop-ipv6-dns-discovery (individual in int area)
|
|
---|---|---|---|
Last updated | 2013-03-02 | ||
Stream | IETF | ||
Formats | plain text pdf html bibtex | ||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 5006 (Experimental) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | Mark Townsley | ||
Send notices to | paul@etri.re.kr |
Network Working Group J. Jeong, Ed. Request for Comments: 5006 ETRI/University of Minnesota Category: Experimental S. Park SAMSUNG Electronics L. Beloeil France Telecom R&D S. Madanapalli Ordyn Technologies September 2007 IPv6 Router Advertisement Option for DNS Configuration Status of This Memo This memo defines an Experimental Protocol for the Internet community. It does not specify an Internet standard of any kind. Discussion and suggestions for improvement are requested. Distribution of this memo is unlimited. Abstract This document specifies a new IPv6 Router Advertisement option to allow IPv6 routers to advertise DNS recursive server addresses to IPv6 hosts. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Applicability Statements . . . . . . . . . . . . . . . . . 2 1.2. Coexistence of RDNSS Option and DHCP Option . . . . . . . 2 2. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 5. Neighbor Discovery Extension . . . . . . . . . . . . . . . . . 4 5.1. Recursive DNS Server Option . . . . . . . . . . . . . . . 4 5.2. Procedure of DNS Configuration . . . . . . . . . . . . . . 5 5.2.1. Procedure in IPv6 Host . . . . . . . . . . . . . . . . 5 6. Implementation Considerations . . . . . . . . . . . . . . . . 6 6.1. DNS Server List Management . . . . . . . . . . . . . . . . 6 6.2. Synchronization between DNS Server List and Resolver Repository . . . . . . . . . . . . . . . . . . . . . . . . 7 7. Security Considerations . . . . . . . . . . . . . . . . . . . 8 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 8 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 9 10.1. Normative References . . . . . . . . . . . . . . . . . . . 9 10.2. Informative References . . . . . . . . . . . . . . . . . . 9 Jeong, et al. Experimental [Page 1] RFC 5006 IPv6 RA Option for DNS Configuration September 2007 1. Introduction Neighbor Discovery (ND) for IP Version 6 and IPv6 Stateless Address Autoconfiguration provide ways to configure either fixed or mobile nodes with one or more IPv6 addresses, default routers and some other parameters [2][3]. To support the access to additional services in the Internet that are identified by a DNS name, such as a web server, the configuration of at least one recursive DNS server is also needed for DNS name resolution. It is infeasible for nomadic hosts, such as laptops, to be configured manually with a DNS resolver each time they connect to a different wireless LAN (WLAN) such as IEEE 802.11 a/b/g [12]-[15]. Normally, DHCP [6]-[8] is used to locate such resolvers. This document provides an alternate, experimental mechanism which uses a new IPv6 Router Advertisement (RA) option to allow IPv6 routers to advertise DNS recursive server addresses to IPv6 hosts. 1.1. Applicability Statements The only standards-track DNS configuration mechanism in the IETF is DHCP, and its support in hosts and routers is necessary for reasons of interoperability. RA-based DNS configuration is a useful, optional alternative in networks where an IPv6 host's address is autoconfigured through IPv6 stateless address autoconfiguration, and where the delays in acquiring server addresses and communicating with the servers are critical. RA-based DNS configuration allows the host to acquire the nearest server addresses on every link. Furthermore, it learns these addresses from the same RA message that provides configuration information for the link, thereby avoiding an additional protocol run. This can be beneficial in some mobile environments, such as with Mobile IPv6 [10]. The advantages and disadvantages of the RA-based approach are discussed in [9] along with other approaches, such as the DHCP and well-known anycast addresses approaches. 1.2. Coexistence of RDNSS Option and DHCP Option The RDNSS (Recursive DNS Server) option and DHCP option can be used together [9]. To order the RA and DHCP approaches, the O (Other stateful configuration) flag can be used in the RA message [2]. IfShow full document text