DNS Referral Response Size Issues

The information below is for an old version of the document
Document Type Expired Internet-Draft (dnsop WG)
Authors Paul Vixie  , Akira Kato 
Last updated 2012-11-10 (latest revision 2012-05-09)
Stream Internet Engineering Task Force (IETF)
Expired & archived
pdf htmlized bibtex
Additional Resources
- Mailing list discussion
Stream WG state WG Document
Document shepherd Peter Koch
IESG IESG state Expired (IESG: Dead)
Consensus Boilerplate Unknown
Telechat date
Responsible AD Ron Bonica
IESG note WG Last Call issued 21 Nov
Send notices to <sra+dnsop@hactrn.net>,<dmm@1-4-5.net>

This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


With a mandated default minimum maximum UDP message size of 512 octets, the DNS protocol presents some special problems for zones wishing to expose a moderate or high number of authority servers (NS RRs). This document explains the operational issues caused by, or related to this response size limit, and suggests ways to optimize the use of this limited space. Guidance is offered to DNS server implementors and to DNS zone operators.


Paul Vixie (vixie@isc.org)
Akira Kato (kato@wide.ad.jp)

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)