Carrier ENUM

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Carrier ENUM NeuStars experienceMarco
Bernardi James Yumarco.bernardi_at_neustar.biz
james.yu_at_neustar.biz
ETSI ENUM Workshop February 2004
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NeuStars mission

• NeuStar is the leading provider of database,
  clearinghouse and registry services that enable
  network operators and service providers to
  interoperate
• NeuStar is a neutral trusted third party
• 350 employees. HQ in Washington DC area
• NeuStar main areas
• Registry services North American Numbering Plan,
  Numbering Pooling, ETNS, .biz, .us, gateway
  for.cn, .tw
• US Number Portability Administration Center
  (NPAC)
• Convergence IP and PSTN ENUM
• OSS clearinghouse services

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Whats carrier ENUM for?

• Used to retrieve routing and addressing
  information associated with E.164 number
• Carrier ENUM is transparent to users
• In mobile networks carrier ENUM can be used for
• Inter-carriers MMS routing (identify home MMSC)
• Inter-carrier SMS routing (identify home SMSC or
  SMPP GW)
• MNP data retrieval (identify routing
  number/prefix)
• SIP server resolution (identify home SIP
  servers)
• Network node identification (identify HLR/HSS,
  P-CSCF)
• Trusted transaction roaming (identify home MSSP)

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Inter-carrier MMS routing

• Problem statement
• Resolution of MMSC based on MSISDN in MNP
  environment
• Analysis of leading digit of MSIDN is not enough
• Solutions
• Query the HLR to retrieve and use IMSI to
  identify the home carrier/MMSC
• Use carrier ENUM to identify home carrier/MMSC

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Multimedia message delivery using carrier ENUM
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3
(MM4 Interface)
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1
B
A
1. A sends a message to Bs MSISDN and the
message is sent to As MMSC. 2. As MMSC uses
Bs MSISDN in the ENUM query. 3. NeuStar returns
the NAPTR RR that contains a mailto URL. 4. As
MMSC determines the MMSC serving B and sends the
message to Bs MMSC. 5. Bs MMSC sends a
notification to B.
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Overview of NeuStars trials

• NeuStars carrier ENUM trial
• Phase I - National
• Started in Spring 2003 and concluded in October
  2003
• Two major US carriers involved
• Proved commercial and technical feasibility
• Signed commercial agreement with these two US
  carriers after trial
• Phase II International
• Ongoing with other US carriers
• Extended to non-US carriers
• Include MSISDNs other than 1 numbers

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Key features (I)

• Application
• Resolution of MMSC in MNP environment
• Reference model
• Tier1 Registry knows MNP data and number range
  assignment data
• No involvement of NRH Carrier
• NAPTR record at individual E.164 number level
• Two options
• 1) NeuStar is only Tier1 Registry, NAPTR records
  stored by carrier
• 2) NeuStar is Tier 1 Registry and stores NAPTR
  records

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Key features (II)

• Option 2 seems to be the preferred one
• Less work for the carrier
• The carrier is the registrar
• The carrier decides the level of information to
  be stored in NAPTR Record associated to an MSDIN
• MMSC address
• Identification of mobile carrier/PoI (minimum
  info)
• No Validation/Authentication Agency
• Number ownership automatically verified based on
  MNP and code range assignment data
• No accreditation

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NAPTR format
NP Data
NeuStar
4.3.2.1.1.8.9.3.0.7.1.foo.foo
Requesting MMSC
Other Data
NAPTR RR(s)

• Example
• 4.3.2.1.1.8.9.3.0.7.1.foo.foo
• IN NAPTR 10 10 u" E2Umms"
  !.!mailto17039811234_at_xyz.com! .

Example Carrier XYZ currently serves
1-703-981-1234, which can be ported or
non-ported. When an MMSC sends a query on
4.3.2.1.1.8.9.3.0.7.1.foo.foo, NeuStar NTS
responds with an NAPTR RR that contains a
mailto URL, mailto17039811234_at_xyz.com.
The MMSC then uses the information to send the
message to Carrier XYZs MMSC.
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Architecture of NeuStar ENUM trial
Carrier 1
VPN
VPN
NTS1
NTS2
Carrier 2
VPN
IP backbone
VPN
Carrier 3
NTS Number Translation Service
Carrier N
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Carrier ENUM - Merits

• Proven DNS technology
• Cheap to support and quick to implement
• Can grow over time - no need to have everybody
  onboard on day one
• No end user/subscriber involvement
• Used by carriers for routing and application
  support
• Same infrastructure/scheme supports multiple
  applications

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Whats next.

• Fragmentation and proliferation of carrier ENUM
  implementations
• Vendor level ?Different providers offering
  different services by using different technical
  solutions
• Industry sector level ? Fixed and mobile
• No need for a common administrative and
  operational framework
• May need for consistent URL contents/formats for
  various applications/services globally
• Market forces will determine the preferred
  solution(s)
• ETSI PlugTest may help vendors and carriers to
  get together and test carrier ENUM
  functionalities

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Questions ?