ENUM Update for
voipeer BOF
Richard Shockey
ENUM co-chair
IETF 63 Paris
A Short History of ENUM RFC 3761
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1999 - IETF ENUM WG formed
Sept. 2000 – IETF ENUM WG – RFC 2916
2001 – Various Workshops (ITU-T, Europe, US, Asia, …)
2002 – ITU -T Interim Procedures (IAB, RIPE-NCC)
– ITU -T generic TLD Investigation
– ETSI TS 102 051 "ENUM Administration in Europe"
• 2003 – ETSI TS 102 172 "Minimum Requirements for
Interoperability of European ENUM Trials"
– IETF new ENUM revision, IANA registered enumservices
– ITU-T final procedures ENUM domain
– ETSI ENUM Workshop (Feb 2004) and Plugtest ( 2004)
• 2004 – IETF RFC 3761
• Enumservices registration
• 1st Commercialization Public ENUM e164.arpa (Austria, et al)
• Commercial Private ENUM Services
• 2005 – APEET Coordination – North American Trials
What is ENUM? - RFC 3761
• take E.164 phone number
• turn it into a FQDN
+1 571 434 5651
1.5.6.5.4.3.4.7.5.1.e164.arpa.
• ask the DNS
• return list of URI’s
sip:richard.shockey@neustar.biz
Phone number IN ..URI OUT
NAPTR RR Structure
preference
order
flag
enumservice
field
regexp
IN NAPTR 10
10 “u” “E2U+ifax”
“!^.*$!mailto:me@domain.foo!”
IN NAPTR 10
10 "u" “E2U+SIP
"!^.*$!sip:+12025332800@network.foo" .
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Order field indicates order of rules in DDDS current ENUM practice is
to set order to common value (10) .
Preference could indicates service selection.
U Flag – Terminal lookup resulting in URI
enumservice field: Specifies protocol to use to communicate with the
E2U service defined in RFC3761 (SIP = RFC 2543) (mailto =SMTP) etc
IESG maintains enumservice registration field oversight in the IANA Registry
Active Delegations in e164.arpa (partial)
•Asia Pacific ENUM
Engineering Task Force
•http://www.apenum.org
Coming Soon
Public ENUM - RFC 3761
• Public ENUM is generally defined as the administrative
policies and procedures surrounding the use of the
e164.arpa domain for TN to URI resolution.
– Policy for branches of the tree are Nation State issues as Directed
by IAB-ITU agreements
– All records are visible on the Internet
• Global Government policy has been to encourage
consumer OPT- IN. Which is generally assumed to be the
number holder as opposed to the carrier of record is the
only entity permitted to create records in e164.arpa.
• How will you register your Phone Number?
– Nation State Issue.Registration Model much like Domain Names…
– Registrars be also be Service Provider or Telecom Equipment
Vendor or Independent “Registrar”
What is Private ENUM ?
• Private ENUM is generally regarded as one or more
technologies (DNS – SIP Redirect- LDAP? ) that permit one
or more entities to exchange phone number to URI data.
Usually in a private secure manner.
• Use of any mutually agreed upon domain
– Could be one or more service providers
– Could be one or more enterprises –
• PBX to PBX inter or intra domain
– Could be private dialing plans
• Principally used by wireless carriers to enable MMS routing
• Could be used by IP network elements to retrieve LNP data
What is Carrier/Infrastructure ENUM ?
• Carrier /Infrastructure ENUM is generally regarded as the use of
RFC 3761 by a highly defined set of service providers to
exchange phone number to URI data, potentially in a private
secure manner to find points of network interconnection.
• The definition of those select service providers are generally
understood to those entities that can issue telephone numbers to
consumers aka “the carrier of record”
• Service providers are looking for NGN signaling infrastructures
to replace SS7 and TCAP queries
• Carrier ENUM is to be assumed as authoritative for all
endpoints service providers choose to exchange data for. There
is no need to OPT-OUT.
Carrier/Infrastructure ENUM options
• 2 URI’s Carrier and Public
– One is a point of interconnection the other is a SIP UA
– Carrier can query either tree
– Probably separate administrations
– Probably still nation state issue ( Layer 9)
A. Use entirely different DNS tree ( private option)
B. Split tree at leaf node of e164.arpa using non terminal NAPTR
records
C. split of e164.arpa tree using 3761 first well known rule
(CC).c.e164.arpa as in 4.4.c.e164.arpa
c.(CC).e164.apra as in c.4.4.e164.arpa
Public ENUM and Carrier ENUM are Orthogonal to each other,
they serve different markets for different reasons.
Lots of Drafts
• Infrastructure ENUM Requirements
draft-lind-infrastructure-enum-reqs-00.txt
• IANA Carrier/User enumservice Registration
draft-pfautz-lind-enum-carrier-user-00.txt
• Combined User and Carrier ENUM in the
e164.arpa tree
draft-haberler-carrier-enum-00.txt
• IANA Registration for an Enumservice Containing
Number Portability and PSTN
draft-livingood-shockey-enum-npd-00.txt
Layer 8 issues ( Economic)
We all know voice is a “bucket of bits” but …
Voice communications is becoming a Transit-Peering model
vs reciprocal compensation.
Transit for Voice is a well understood business model..peering for
voice is not.
Service providers going to all IP – SIP core networks.
Default PSTN routing for SIP to SIP session routing by
service providers is not economically sustainable.
Goal IP end to end service/application delivery.
What does this have to do with voipeer?
Its all about peering.
But peering is a VERY complex subject.
ENUM (Public-Private-Infrastructure) only solves the Layer
7 number translation issue.
Public ENUM is slow to take off for any number of reasons.
“Phone numbers are dead” but ..
we’ll all be dead before they go away.
Questions ?