[ih] Internet-history Digest, Vol 10, Issue 1

[Dan York]

Scott,

> On Jul 6, 2020, at 3:08 PM, Scott O. Bradner via Internet-history <internet-history at elists.isoc.org> wrote:
> 
> enum is well used inside telephone companies to do number mapping (or so I'm told)

Yes, ENUM is heavily used within companies involved with VoIP. In a non-public setting, it is often called one of “private ENUM”, “carrier ENUM”, or “infrastructure ENUM”, with different nuances. It is part of what is used in “voice peering”.  Before joining ISOC in 2011, I worked for five years at a company providing voice application services and private ENUM was a critical component of our call routing infrastructure.

> but the public enum died because of privacy concerns

Yes, that was what I saw as one the major issues. Privacy of both user information and also carrier info. There were, for instance, some scripts out there that would walk an entire ENUM tree in DNS, capture all the addresses, and then feed those into another script that would then connect to those addresses to deliver voice messages. I don’t remember their exact names, but I do remember researching what these various scripts did. Separately, because DNS queries are public, there was the exposure of customer information if someone could be in the right place to watch the queries. For those reasons and more, public ENUM never took off in the way it was originally envisioned.

Regards,
Dan (who was a big fan of the idea of public ENUM back when he worked with SIP / VoIP more)