19 March 2007 ed.lewis@neustar.biz 1

E.212 ENUMService Type DefinitionE.212 Parameters for the "tel" URI

Edward Lewis

NeuStar

IETF 68 ENUM WG meeting

19 March 2007 ed.lewis@neustar.biz 2

Back-to-Back Items

• draft-lewis-enum-enumservice-e212-00.txt– To register "E2U+E212" as enumservice– Indicates NAPTR has ITU E.212 infomation

• draft-lewis-enum-teluri-e212-00.txt– To define parameters in tel: for E.212

19 March 2007 ed.lewis@neustar.biz 3

Plans for the two

• Go over comments received so far, get more while here

• Edit the documents in the coming week(s) post IETF68

• Submit again as directed (WG or not)

19 March 2007 ed.lewis@neustar.biz 4

E.212 for IETF'ers

• E.212 is an ITU document/standard defining meta-data for a mobile-phone telephone number– MCC (Mobile Country Code)– MNC (Mobile Network Code)– MSIN (Mobile Subscriber Identification #)– IMSI (International Mobile Subscriber

Identity) - the concatenation of the other 3

19 March 2007 ed.lewis@neustar.biz 5

A diagram

MCC MNC MSIN

IMSI

MCC - 3 digitsMNC - 2 or 3 digitsMSIN - up to 10 digitsIMSI - up to 15 digits

19 March 2007 ed.lewis@neustar.biz 6

Why IETF documents?

• This is about ENUM– Wanting to store the ITU-defined

parameters in ENUM– This isn't so much about E.212, 'cept that

that is the "payload"

19 March 2007 ed.lewis@neustar.biz 7

draft-lewis-enum-enumservice-e212-00.txt

• First, it's a -00 individual, happy to make it a WG document

• Fills in an ENUM service "application"

• E2U+E212 means the NAPTR RR has a tel: URI (with extensions in the other draft)

19 March 2007 ed.lewis@neustar.biz 8

Comments on that one

• Would like a good use case– Fair enough, the draft is minimal and am

happy to add that. Still in the process of writing it.

• Is it worth getting a non-SIP ENUM extension defined?– Suggestion to use an experimental (x-) but

really want a "real" definition

See next slide.

19 March 2007 ed.lewis@neustar.biz 9

Use case

• With number porting, can't tell the carrier by the number alone– Knowing the receiving operator of a call

could impact business decisions• In Softswitch draft "...interconnection only with

trusted carriers"

– For IM knowing the MCC+MNC can determine the receiving server name

19 March 2007 ed.lewis@neustar.biz 10

More comments

• What about "aux-info:e212"?– Although workable, a few reservations

• We/WG don't have other "aux-info's" in mind, I don't like to generalize from a single case

• E.212 is subjectively significant enough to stand on its own, and is reliant on an external (ITU) definition

• Linking in other (unknown) types would likely slow this process

19 March 2007 ed.lewis@neustar.biz 11

First doc question to WG

• Should this be adopted as WG item?– What is missing from the application and

supporting document?

• Sub-note: I couldn't find a reliable "how to" to follow when submitting these drafts, so I "undercut" the submission

draft-ietf-enum-enumservices-guide-03.txt

19 March 2007 ed.lewis@neustar.biz 12

draft-lewis-enum-teluri-e212-00.txt

• This document defines parameters for the tel: URI to hold the E.212 data– In the spirit of RFC 4694, but for different

data

• Four parameters are defined, as per earlier slide (MCC, MNC, MSIN, IMSI)

19 March 2007 ed.lewis@neustar.biz 13

My goal

• I am interested in retrieving the MCC and MNC for a telephone number via ENUM

• The draft includes MSIN and IMSI parameters for completeness

19 March 2007 ed.lewis@neustar.biz 14

Comments

• This draft ought to go to IPTEL– No response to that yet from me

• What's E.212?– Should this draft explain it or just refer to

the ITU document (now freely available)?– When I prepared the draft, I went for not

including an explanation but can be convinced otherwise

19 March 2007 ed.lewis@neustar.biz 15

More comments

• Need an illustrative use case– Working on that, went for brevity in the -00

• The ABNF is wrong– A few pointed this out, you are all right, I'll

fix that

• The URI is wrong– Sorry - sigh, I wrote the draft on an

airplane and it shows ;) (Goes for the ABNF too.)

19 March 2007 ed.lewis@neustar.biz 16

Yet more comments

• MCC+MNC xor IMSI?– Should the syntax require either both MCC

and MNC be present or the IMSI be present?

– My response is - that's the probable use case, but does this have to be encoded in the syntax rules? I prefer to let the syntax be freer than the use

19 March 2007 ed.lewis@neustar.biz 17

And more comments...

• Isn't it unwise to have the IMSI, MSIN, and maybe even the MCC and MNC in a public database?– I'd agree with that, but the drafts are just

providing a means to put this in ENUM and not saying that the data would be public

– Not all DNS servers are on public networks

19 March 2007 ed.lewis@neustar.biz 18

Second doc questions

• Should this be an ENUM WG doc or go ask IPTEL WG to adopt this?

19 March 2007 ed.lewis@neustar.biz 19

Well, I'm out of slides

• Discussion?

19 March 2007 ed.lewis@neustar.biz 20