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IETF- ENUM

ITU-T Workshop for International Regulators17 January 2001 – ITU HQ Geneva

Richard Shockey

IETF ENUM Work Group Co-Chair

Senior Technical Industry Liaison

NeuStar, Inc.

1120 Vermont Avenue N.W.

Washington DC, 20005

rich.shockey@neustar.com 202.533.2811

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Introduction – Why are we here?Introduction – Why are we here?

From a delayed contribution to SG2 by France :

– “ ENUM protocol is defined by RFC 2926, aiming at translating the numbers stemming form the ITU-T E.164 Recommendation into Internet Domain Names; ENUM is an opportunity for developing the information society.”

– “As a matter of fact, ENUM allows to use a traditional telephone number in the context of different communications media, in particular those rising from the development of IP networks (e-mail, VoIP, …) and therefore, could facilitate the penetration of new applications into the mass market easily ( this market is accustomed to E.164 numbers).”

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Introduction – Why are we here?Introduction – Why are we here?

From a delayed contribution to SG2 by France:

– “This is a key opportunity for Internet communications service providers, who could tailor their services to be accessible by means of E.164 numbers, widely in use throughout the world ( much more than Internet domain names or e-mail addresses ).”

– “Therefore, ENUM is a chance for the “Internet world” to enter the E.164 naming system, which has the advantages of being stable, world-wide used and well-digested by end users.”

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OverviewOverview

ENUM is part of Convergence– ENUM is part of series of technical initiatives underway

in both the IETF and ITU to develop Internet Telephony Standards.

Call Setup – H.323 – SIP

Quality of Service – DIFFSERV – INTSERV – MPLS

PSTN – IP Interworking H.248/MEGACO

FAX – T.37 T.38 – RFC 2503

Mobile – 3GPP related

ENUM is about new service creation

But we must address naming and numbering issues

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Problem StatementProblem Statement

How do you find services on the Internet if you only have a telephone number [E.164]?

How can we enable new IP services while creating new competitive markets and protect consumer choice,etc?

How can consumers and carriers have equal access to these new opportunities?

How do we create a trusted TN based resource for information about those services?

How do you make this simple, easy to use, without “reinventing the wheel”?

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Solution ENUM / DNS Directory ServiceSolution ENUM / DNS Directory Service

• Put telephone numbers into the global Domain Name System [DNS]

ENUM WG formed and operates within in the Internet Engineering Task Force

– Core protocol work completed - RFC2916

RFC2916 defines the use of DNS resource records to find optional :

– E-mail addresses

– Voice over IP SIP / H.323 servers

– Voice Mail servers

– Fax Machines

– New and yet undefined services !

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Why DNS?Why DNS?

It’s there...– It works... It’s global... It scales... It’s

fast... It’s open.

ENUM enabled DNS creates a low cost, shared Service Control Point like infrastructure for IP services

Goal – Telephone Number IN …. URL out

Key to TN related services offered by providers over IP

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Why E.164 Telephone Numbers?Why E.164 Telephone Numbers?

Familiar to consumers

TN’s are linguistically neutral– Internationally Understood

E.164 Plan is “Authoritative” – Trusted to produce consistency across the

PSTN.

A Billion devices or so do not have QUERTY Keyboards….

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How Does ENUM Work?How Does ENUM Work?

Take a fully qualified E.164 telephone number and create a DNS entry in a single highly defined and structured domain.

The search for resources on the internet associated with + 1 202-533-2811 becomes a DNS look up to: 1.1.8.2.3.3.5.2.0.2.1.e164.arpa

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RFC 2916RFC 2916

ENUM is not about putting telephone numbers into any domain..it specifically about putting E.164 numbers into e164.arpa ( a subtle distinction )

From RFC2916: – “The domain "e164.arpa" is being populated in order to provide the

infrastructure in DNS for storage of E.164 numbers.”

– “This memo requests that the IANA delegate the E164.ARPA domain following instructions to be provided by the IAB. Names within this zone are to be delegated to parties according to the ITU recommendation E.164. The names allocated should be hierarchic in accordance with ITU Recommendation E.164, and the codes should assigned in accordance with that Recommendation.”

Private dialing plans can be accommodated in any domain.

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Why e164.arpa ?Why e164.arpa ?

The e164.arpa domain was selected by the Internet Architecture Board specifically for this purpose with the concurrence of the ITU

.ARPA is designated by the IAB for Internet Infrastructure issues– in-addr.arpa (reverse IP address look up)

.ARPA is a well managed, stable and secure operational environment under IAB supervision

Single domain structure under e164.arpa becomes the authoritative “root” for E.164 telephone numbers

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Simple ENUM Flow ChartSimple ENUM Flow Chart

SIP Proxies

ENUM Global Directory (DNS)

Equates 1(202) 533-2811 to sip:rich.shockey@carrier.net to enable Voice over IP using SIP

Proxy Queries DNS for SIP Address based on TN

Internet

DNS

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What ENUM is not….What ENUM is not….

ENUM is not about carrier selection (selection of carrier within a given service type)

ENUM is not about telecom bypass– An alternative to circuit switched technology

ENUM does not change the Numbering Plan– ENUM does not change ITU-E.164– ENUM does not change existing telephony numbering or

its assignments in anyway – ENUM does not exhaust national number plans

May conserve numbering resources

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Privacy ConsiderationsPrivacy Considerations

We believe that RFC 2916 is consistent with current EC policy on Privacy and Data Protection

There is no requirement for WHOIS

ENUM is a Opt-IN system

ENUM does not expose personal data or personal preferences for call processing– ENUM is essentially routing data – a

shared Service Control Point

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ApplicationsApplications

Internet

ENUM

Directory

TelephonyNetworks

Enabled Enabled ApplicationsApplications

• Voice over IP

• Unified Messaging

• Instant Messaging

• IP Fax

• Personal Web Pages

E.164 E.164 NumbersNumbers

• 10 Digit10 Digit

• 800800

• InternationalInternational

PrivatePrivate

NetworksNetworks

Internet Domain Internet Domain Name AddressesName Addresses

DNSDNS

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ITU – IAB / IETF AgreementsITU – IAB / IETF Agreements

Liaison Statement issued by Study Group 2 now officially RFC 3026

IETF – ITU Agree on delegation model that completely follows the ITU-T E.164 plan for inclusion into e164.arpa

Operational Responsibility is at the IAB, while Administrative Management is at ITU.

- e164.arpa geographic zones controlled by appropriate Member State.

– ITU will insure that Member States have authorized the inclusion of their Country Code in e164.arpa

– ITU to coordinate with RIPE NCC as the Root Administrator– IETF - ITU jointly work together in moving forward

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Member State IssuesMember State Issues

How are the National Delegation Servers for each CC to be managed?

– From RFC 2916: “Holders of E.164 numbers which want to be listed in DNS should contact the appropriate zone administrator in order to be listed, by examining the SOA resource record associated with the zone, just like in normal DNS operations.”

– This means Member States are the ENUM Zone Administrators for their CC’s

Who manages these servers is a Member State issue.

What is the process and criterion used for ENUM Administrator selection?

What capabilities should ENUM Administrators have?– Financial / Technicial

What performance requirements should ENUM Administrators have?

What Regulatory Rules must they operate under?

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Next Steps…Next Steps…

ENUM Technical – Testing and TrialsVendors put ENUM capable DNS Resolver into Internet Telephony Products

Create ENUM / DNS Operational Metrics– Security – Redundancy

Administrative – Member State DefinedEducational Process within Communities of Interest

ENUM Operations– How do you authenticate the identity of the subscriber

for ENUM services ?– Who are ENUM Registrars and what are they

responsible for?– How do you validate ENUM data for potential users

( Add - Modify – Delete ) NAPTR list of services and preferences)

– How is the data provisioned to the CC zone NS

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Next Steps…Next Steps…

– What happens when a TN is disconnected? How and when will ENUM RR be deleted?

– What is the role of the incumbent PSTN carrier?– How is competition promoted in the process?

Existing Policy models within Member States offer guidance to :

Promote Consistency with E.164 Number Plan and Number Portability requirements

Prevent Number Slamming

Prevent Number Hijacking

Protect Consumers Interest

Protect Consumer Privacy

Equal Access to RR’s by all qualified carriers and service providers

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ENUM ResourcesENUM Resources

ENUM Charter

http://www.ietf.org/html.charters/enum-charter.html

ENUM Core Protocol

ftp://ftp.isi.edu/in-notes/rfc2916.txt

ENUM WG Requirements

http://www.ietf.org/internet-drafts/draft-ietf-enum-rqmts-01.txt

ENUM Call Flows

http://www.ietf.org/internet-drafts/draft-lind-enum-callflows-01.txt

ENUM Operations Issues

http://www.ietf.org/internet-drafts/draft-ietf-enum-operation-01.txt

ENUM Administration in the United Stateshttp://www.ietf.org/internet-drafts/draft-pfautz-yu-enum-adm-00.txt

Voice Profile for Internet Mail

ftp://ftp.isi.edu/in-notes/rfc2421.txt

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ENUM ResourcesENUM Resources

IETF-ITU Liaison Statement

ftp://ftp.isi.edu/in-notes/rfc3026.txt

NAPTR Resource Records

ftp://ftp.isi.edu/in-notes/rfc2915.txt

A DDDS Database Using The Domain Name System

http://www.ietf.org/internet-drafts/ draft-ietf-urn-dns-ddds-database-01.txt

Dynamic Delegation Discovery System (DDDS)

http://www.ietf.org/internet-drafts/ draft-ietf-urn-ddds-02.txt

URI Resolution using the Dynamic Delegation Discovery System

http://www.ietf.org/internet-drafts/ draft-ietf-urn-uri-res-ddds-01.txt

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Web ResourcesWeb Resources

International Telecommunications Union– http://www.itu.int/infocom/enum/

CyberTelecom– http://www.cybertelecom.org/teleph.htm