Title: On adding a wildcard to the *.travel domain.
Submission Date: 2006-10-12

From: Olaf Kolkman(IAB) 
To: Lyman Chapin - Chair Registry Services Technical Evaluation Panel
Cc: Thomas Narten - IETF Liaison to the ICANN Board;
iab@ietf.org


Dear Lyman Chapin,


The Internet Architecture Board has become aware of the request by
the Tralliance registry to add a wildcard in the .travel TLD zone.
We would like to point out that the IAB has published a statement
in 2003 [1] outlining the architectural trade-offs of wild-cards
in registry- class zones.

The conclusions of that statement still hold. There is no indication
that the behavior of MTAs and other critical applications has
significantly been improved to deal with the presence of wild-cards
in TLD zones.

Without the intent of becoming involved in judging the merits of
this particular case, we want to particularly draw your attention
to the guideline and one of the recommendations from our 2003 document:

"Proposed guideline: If you want to use wildcards in your zone and
understand the risks, go ahead, but only do so with the informed
consent of the entities that are delegated within your zone."

and

"... [The IAB] strongly suggest that the burden of proof in such  
cases [using wildcards in "registry"-class zones] should be on the  
registry to demonstrate that their intended use of wildcards will not  
pose a threat to stable operation of the DNS or predictable behavior  
for applications and users."

These  highlight that there is potential damage for third parties  
that the registry has contact with ---the entities that are delegated  
within the zone---  and third parties that the registry does not have  
contact with --- all Internet users and their applications.

For more information please consult the original recommendation [1].

Finally, we refer you to RFC4592, a technical document.  It provides  
a detailed description of how wildcards work. This may or may not  
apply to the assessment of the Tralliance request depending on the  
exact resource record types that are added to the wildcarded names.


[1]: http://www.iab.org/documents/docs/2003-09-20-dns-wildcards.html


On behalf of the IAB,

--Olaf Kolkman