Ever since Neustar announced they signed a deal with GSMA to oversea global database for the mobile operators last week (see also Washington Post), there are many debates about the deal online.

“Neustar, a company that should certainly know better, has announced that they’re going to create a .gprs TLD to serve the mobile phone industry This, of course, requires creation of a private root zone, against the very strong warnings in RFC 2826” said Steven Bellovin.

To the more supportive John Levine: “This isn’t quite as stupid as it seems. The GSM industry needs some way to maintain its roaming user database, the database is getting considerably more complicated with 3G features, and it looks to me like they made a reasonable decision to use DNS over IP to implement it rather than inventing yet another proprietary distributed database.”

Even Paul Vixie who has been one of the most vocal opponents of alt. root chipped in, albeit in a slightly positive tone to many people surprise: “oh and one more thing. a small technical matter, insignificant next to the democracy-related points you raised. neustar isn’t doing anything wrong — the “root” they’ll operate will only be seen by GPRS cell towers, not by end-user handsets.”

Let’s start by clarifying what Neustar is doing¹: they are providing a global distributed database for SIP URLs, especially for mobile operators who have implemented IMS (which is essentially modified SIP) using DNS technology. Specifically a variation of ENUM known as Infrastructure ENUM² that differs from (User) ENUM in its policies: the numbers are delegated to carriers & operators and not end-users. The controversial is that they are using a new TLD called .GRPS using their own alt. root server and many people jumped at the word new TLD and “alt. root”.

For the record, I am a believer of The Single Root (see RFC 2826 IAB Technical Comment on the Unique DNS Root). However, in this case, I think there are justifications in what Neustar is doing.

First, GSMA is already using an alt. root system with the .gprs for among their operators for their GPRS peering³. What the deal essentially is to outsource that DNS operation to Neustar. In other words, Neustar did not intentionally create a new root or TLD; they are taking over an existing operation and it is unreasonable to expect them to “conform” to whatever norms we have.

Second, there are approximately 1.5b mobile phone users. Put that into perspective, that is more than the total numbers of Internet users at this moment. So as we are converging between the mobile and Internet, be glad they (i.e. GSMA) made no demands from us (i.e. Internet) to conform to their norms and their root because really, they are much bigger than us.

Actually I am glad that their alt. root is now in the hands of competent DNS engineers who understand the Internet (particularly ICANN). Maybe we stand a chance to fold the two DNS system so that .GRPS is a recognizable ICANN TLD. Unfortunately, this is going to be take a while because no one knows when is the next time ICANN is going to ask for proposal for TLDs. Given such uncertain environment, you really cannot blame commercial operators moving ahead with their own root and TLD.

But all these arguments about alt. root and TLD is pretty moot because unlike User ENUM where e164.arpa is designated as the “golden root”, we have no such “golden root” in Infrastructure ENUM. So even if the DNS root and TLD converged, we still need to decide a “golden root” for Infrastructure ENUM which is not likely to happen in any short timeframe.

¹ Based on their press releases and some discussion I had with Neustar people.

² Incidentally, Infrastructure ENUM is a new work item for ENUM Working Group that I blogged about a month ago.

³ See Comfone, a GRX-provider: “Our DNS is set up according to GSMA guidelines and is a mirror of the .gprs Root DNS of GSMA.”