understanding enum current status n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Understanding ENUM & Current Status PowerPoint Presentation
Download Presentation
Understanding ENUM & Current Status

Loading in 2 Seconds...

play fullscreen
1 / 14

Understanding ENUM & Current Status - PowerPoint PPT Presentation


  • 73 Views
  • Uploaded on

Understanding ENUM & Current Status. Kmccandless@illuminet.com. Network Planning August 21, 2001. ACRONYMS. A Record (A host Address) ARPA (Advanced Research Project Administration) DNS (Domain Name Server) E.164 (ITU telephone numbering plan)

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Understanding ENUM & Current Status' - shilah


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
understanding enum current status

Understanding ENUM&Current Status

Kmccandless@illuminet.com

Network Planning

August 21, 2001

slide2

ACRONYMS

ARecord (A host Address)

ARPA (Advanced Research Project Administration)

DNS (Domain Name Server)

E.164 (ITU telephone numbering plan)

IETF (Internet Engineering Task Force)

ITU (International Telecommunication Union)

MGC (Media Gateway Controller)

NAPTR (Naming Authority Pointer Record in a DNS)

NS (Authoritative Name Server, DNS record)

RTP (Real-Time Transport Protocol)

SG (Signaling Gateway)

SGA (Study Group A of the International Telecommunication Advisory Committee, US policy and regulatory aspects telecommunications services.)

SIP (Session Initiation Protocol)

URI (Uniform Resource Identifiers)

slide3

The root node

""

...

.com

.net

.arpa

second-level node

second-level node

second-level node

e164.arpa

in-addr

third-level node

third-level node

1.e164.arpa

7.1.e164.arpa

...

1.2.3.4.5.5.5.2.3.7.1.e164.arpa

DNS Hierarchy

This slide is from draft 4 of the Ad-Hoc Study Group A report on ENUM

slide4

TIER 0, I, & II

Tier 0

Directs the DNS query to the controlling country based

on country code. This is done by providing the NS record

of Tier I.

e164.arpa

Tier I

Tier I directs the DNS query to the customer Tier II provider.

The NS record is provided for the subscriber’s telephone

number.

1.e164.arpa

Tier II

  • DNS service that stores a list of service specific internet
  • addresses in the form of URI’s in a DNS resource record
  • called NAPTR. TIER II will return the full list of Internet
  • addresses associated with the E.164 number being queried.
    • IN NAPTR 10 10 "u" "sip+E2U" “!^.*$!sip:kmccandless@illuminet.com!”
    • IN NAPTR 10 10 "u" "mailto+E2U" “!^.*$!mailto:kmccandless@illuminet.com!”
    • IN NAPTR 10 10 "u" ”fax+E2U" “!^.*$!mailto:faxmachine5@illuminet.com!”
    • IN NAPTR 10 10 "u" ”print+E2U" “!^.*$!mailto:printer03@illuminet.com!”
    • IN NAPTR 10 10 "u" "tel+E2U" “!^.*$!tel:+19135551212!”

.1.e164.arpa

slide5

Example

  • Requestor types into their browser a E.164 number:
        • +19135551212
  • The requestor’s software converts the phone number
  • With country code into a ENUM ready number.
  • 2.1.2.1.5.5.5.3.1.9.1.e164.arpa

Requestor

.

The Root

Node

The root node is the root server that directs queries to the

appropriate zone. .arpa, .com, .org, etc

Tier 0 database will direct the request to the North

American Tier I database(s) based on the country code of 1.

(Assumes specific model for Tier I.)

e164.arpa

Tier 0

1.e164.arpa

The Tier I database, for country code 1, could be two sub-tiers;

one sub-tier to receive country code 1 and the other to segment

the NPAs within North America. The NPAs could be grouped by

individual countries within North America.

Tier I

.1.e164.arpa

The Tier II database will return to the requesting computer

the list of service specific addresses (URIs) associated with the

queried number.

Tier II

slide6

Example Continued

.

FAX

e164.arpa

In this continued example, a requesting computer

can deliver information to several devices just by

knowing a phone number. This could be a number

from a business card. Now the user can send

information to a business associate based on the

options returned by the query.

1.e164.arpa

.1.e164.arpa

slide7

TIER 0 – II DATABASES

  • Tier 0:
    • Only one database controlled by RIPE NCC and ITU (policy only)
    • Contains participating country codes.
  • Tier I:
    • Within North America there could be several Tier 1 databases.
    • There would have to be a delegation process from the North Americancountry code of 1 to a NPA sub-database. The NPAs could be grouped by individual countries in North America.
    • Contains the fully qualified E.164 numbers and pointers to Tier II provider for the subscribers URIs.
  • Tier II:
    • Competitive with many Tier II providers
    • Hosting the subscriber’s URIs
slide8

Countries Covered by the North American Code of 1 (One)

United States

Canada

Jamaica

Bahamas

Grenada

Barbados

Barbuda & Antigua

St. Kitts & Nevis

St. Lucia

St. Vincent & the Grenadines

Dominica

Trinidad & Tobago

Dominican Republic

Anguilla

Bermuda

British Virgin Islands

Cayman Islands

Commonwealth of the Northern Mariana Islands

Guam

Montserrat

Puerto Rico

Turks & Caicos Islands

US Virgin Islands

problem
Problem
  • More then one Country under the 1 code for North America
  • Who will administer the Tier I database for North America?
  • What happens if one of the other countries within North America respond to the ITU before the United States and are granted provisioning rights to the North American Code of 1?
  • Do we want to be involved with all the other Countries in North America for ENUM deployment?
slide10

A Better Approach

.e164.arpa

Tier 0 (Containing list of country codes)

Tier I for North America (Containing NPA pointers

for each country that is a subset of the 1 code)

1.e164.arpa

.1.e164.arpa

Barbados NPA

.1.e164.arpa

ETC

…..

.1.e164.arpa

United States NPAs

.1.e164.arpa

Jamaica NPA

.1.e164.arpa

Dominica NPA

.1.e164.arpa

Canada NPAs

.1.e164.arpa

Barbuda & Antigua

NPA

.1.e164.arpa

Grenada NPA

Tier I+(subset) would allow each

country in North America to manage

their own Tier I equivalent database.

Any Tier II

Provider

a better approach
A Better Approach
  • Allows each country in North America to maintain their own Tier I equivalent database.
  • Reflects the fact that the United States is not the only entity within the 1 (one) code.
  • Once routed to the individual country Tier I database, the subscriber’s phone number and not the NPA will determine the Tier II provider for NAPTER records.
slide12

ENUM enables PSTN to SIP calls

ENUM

Server

ENUM

21215553191.e164.arpa

Signaling

Gateway

STP

4

5

Invite 3

Proxy

Server A

MGC

Invite: 19135551212From: 12025551212

SIP: UserB@illuminet.com

Invite 6

User A

Proxy

Server B

1

2

MediaGateway

SSP

Invite 7

Invite: SIP: UserB@illuminet.comFrom: 12025551212

8

User B

  • In this example, User A attempts to contact User B who is on a VoIP network and uses a SIP phone.
  • User A dials the global E.164 number for User B.
  • The SSP sends an IAM message via SS7 to a SG (which is part of the Media Gateway Controller / Media Gateway).
  • The Media Gateway Controller sends an invite message to the nearest Proxy Server.
  • Proxy Server A does not know User B address; therefore it contacts an ENUM Server.
  • The ENUM Server returns the address of User B.
  • Proxy A sends invite message to User B’s Proxy Server B
  • Proxy Server B passes the invite to User B
  • If User B accepts the call, there is a two-way RTP path established between User B and the Media Gateway controller. A two-way path is also established between the Media Gateway and User A. At this point User A is able to communicate with User B.
competitive model advantages disadvantages
Competitive Model – Advantages & Disadvantages

Advantages:

  • Any DNS provider can set up ENUM like structure in any Top Level Domain.
  • The DNS provider could provide all Tiers, 0 – II, and possibly root.
    • Provide Registrar Functions
    • Provide Register Functions
  • Can offer ENUM services outside of the United States.

Disadvantages:

  • Will require clients and non-client to have resolver software.
  • Performance issues are a concern for clients and none clients
  • Major performance concerns for VoIP providers when ENUM is used as a location server.
  • Not compliant with RFC2916 from the IETF.
  • Not supported by the ITU-T Study Group 2.
status on enum
Status on ENUM
  • US Department of State Ad-Hoc Study Group A on ENUM
    • Completed recommendation to Department of State.
      • Document Released on July 6.
    • Presentation given to Study Group A on July 31.
  • Recommendations
    • Recommendation for US participation in ENUM.
    • Provides guidance to respond to ITU.
    • Use the single zone per RFC 2916 (.arpa).
    • Understand that there will be competitive models deployed.
    • ENUM is an Opt In service.
    • Privacy Protection is a high priority.
  • Scheduled Events
    • August 27: First face-to-face meeting of the new ENUM Forum
      • Agree to forum principles and procedures
      • Agree to work plan
      • Pick leaders for the 5 proposed subcommittees.
    • September 4: Next Study Group 2 ITU-T meeting.