Alternatives for Providing Routing and Location Information

Alternatives for Providing Routing and Location Information to support Emergency Calling from IP Enterprises

Prepared For:

NENA VoIP Meeting on behalf of SBC, BellSouth, Qwest

July 29, 2003

Telcordia Contacts:Nadine Abbott(732) [email protected]

An SAIC Company

Telcordia Technologies – Confidential Restricted AccessThis document contains proprietary information that shall be distributed, routed or made available only within

Telcordia Technologies, SBC, and BellSouth, and Qwest except with written permission of Telcordia Technologies.

VoIP 9-1-1 location id migration – nbaTelcordia Technologies Proprietary - Internal use only. See proprietary restrictions on title page.

2

Purpose and Objectives

Provide an overview of a possible evolution for supporting location information for emergency calls originated from IP networks. – High-level information flows

Discussion to identify path forward– Identify and solicit comments on new interface functionality that

needs to be supported.


3

Terms

ALI = Automatic Location Identification (including street address, detailed location, etc.)

CBN = Call Back Number (a dialable NANP number, or Telephone Number [TN] assigned to the IP Enterprise)

CGL = Calling Geodetic Location (lat/long) as defined in ANSI T1.628 for ISDN and for SS7.

CMF = Call Management Function (generic term used to represent various VoIP architecture functions that may be used to support call management, e.g., H.323 Gatekeepers, SIP Servers, Megaco Call Agents, etc.)

LIS = Location Information Server (or application/function) ELIN = Emergency Location Identification Number = dialable NANP

number used to identify an Emergency Response Location on a customer’s premises; usually allocated from among the customer’s DID numbers.

ERL = Emergency Response Location = a specific geographic area on a customer’s premises with a unique association to a PSAP ESN.


4

Terms (cont.)

“Address Token” = an identifier assigned/administered by the Network LIS and associated with a particular ERL. (This term differs from ELIN in that it need not be a dialable NANP number.)

ESN = Emergency Service Number = an up to 5-digit identifier uniquely associated with an ESZ and a PSAP DN.

ESZ = Emergency Service Zone = a specific geographic area with a unique association with police, fire, and emergency medical response agencies.

“Shell record” = A record that includes some, but not all of the required information for processing an emergency call. Some examples for various scenarios:

– An ALI DB shell record for an ERL might include an Address Token identification, information about the carrier, the IP enterprise customer, and MSAG validated address information for the ERL, but not a Telephone Number. This shell record might be used to create temporary records for a CBN in real time. May be supplemented with additional location details in real time during a call, or may be used to create initial temporary records for a CBN.

– An SRDB shell record for a TN might include a default ESN or an identifier for a Network LIS to be queried for routing information.


5

Terms & Abbreviations (cont.)

ALI DB – Automatic Location Identification Data Base DBMS – Data Base Management System LIS – Location Information Server PS-ALI – Private Switch ALI PSAP – Public Safety Answering Point SRDB – Selective Routing Data Base VoIP – Voice over IP CAS – Call Associated Signaling NCAS – Non-Call Associated Signaling SIP – Session Initiation Protocol


6

Assumptions

Assume that the Local LIS will perform address validation for all of its ERLs before implementing emergency calling from VoIP devices.

Assume that the Local LIS will periodically request re-validation of its ERL address information, scheduled as required to reflect expected frequency of changes in MSAG data.

Assume that Local LIS will be able to track locations of the served VoIP devices and determine when a device has moved between ERLs (for NCAS-like solutions-see slide 13).

Assume that the Local LIS will able to accept and store Address Tokens received from the Network LIS, and associate them with the appropriate ERL and address information.


7

Assumptions

Assume that for scenarios when the Network LIS is in the critical path for real-time processing, it will be designed so as to have the same availability, reliability, and accessibility characteristics as the SRDB and ALI DBs.

Assume that at a minimum, for all alternatives, new connectivity and an interface between the Local LIS and the Network LIS will need to be supported. – For some scenarios, connectivity may be established only as

needed for address validation

– In other scenarios, interface also used to push location information into the E9-1-1 network and/or data bases.


8

LAN

Address Validation & Re-Validation

Originating Network

E9-1-1 Tandem

Network LIS

VoIP device

Local LIS

Local VoIP CMF

Address Validation Request (ALI)

Address Validation Response(success; Address Token*)

Address Re-Validation Request (ALI, Address Token)

Address Re-Validation Response (success)

• • •

• • •

Notification of MSAG changeAddress changes

MSAGDBMS

ALI

ESN or equiv.

LIS = Location Information ServerCMF = Call Management Function

e.g., H.323 Gatekeeper, SIP Server, Call Agent* Consider also including routing

information equivalent to ESN – what?


9

Possible Ways to Leverage IETF DHCP and Geopriv WG Solutions (1) Call Associated Soln.

VoIP device

Local LIS

Network LIS

Address Validation

DHCP Server

DHCP query

DHCP query [+ Circuit ID]

Location query:

[IP address, Circuit ID]

[IP address, location object]

[location object]

e.g., LAN switch

VoIP Network

VoIP Call Setup [Callback ID, Location Object]

Map Circuit ID to Location Object


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Example Way to Leverage IETF DHCP and Geopriv WG Solutions (2) – with Transitional Non-Call Associated Solution

VoIP device

Local LIS

Network LIS

Address Validation

DHCP Server

DHCP query

DHCP query [+ Circuit ID]

NENA XML near real-time updatesof changes(Callback ID, Address Token)

Location query:

[IP address, Circuit ID]

[IP address, location] [location]

e.g., LAN switch

VoIP Call Setup [Callback ID]

Local VoIP CMF

Map Circuit ID to Location Object

“registration” [Callback ID, IP Address]

[Callback ID, IP Address]


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Optional E9-1-1 DB ALI shell record creation; after Address Validation (Re-Validation) for NCAS-Like Transitional Solutions

DBMSALI DB

Create Shell Record (Address Token, ALI)

Acknowledgement

For all Address Tokens:

LAN

Originating Network E9-1-1

Tandem

Network LIS

VoIP device

Local LIS

Local VoIP CMF


12

(Optional) E9-1-1 DB Initial CBN record creation after Address Validation (or Re-Validation) for NCAS-Like Transitional Solutions

Create/Update Response[success]

Create/Update Request[CBN, Address Token, (optional)

additional location details]

For all Call Back Numbers/IDs (CBNs):

LAN

Originating Network E9-1-1

Tandem

Network LIS

VoIP device

Local LIS

Local VoIP CMF


13

IP device gets location

NCAS-Like Transitional Solution

ALIDBSRDB

Emergency call

origination

Network LIS SRDB

ALI DB

PSAP

Update Request [CBN, Address Token, (opt. additional details)]

Update Response (success)VoIP Call

setup (Caller ID)

Call setup (Caller ID)

Call setup

(CBN) Routing Query (CBN)

Response (ESN)

Call setup (CBN)Query (CBN)

Response (ALI)

Routing Query (CBN)

Response (ESN/PSAP DN)

Location Query (CBN)Response (CBN, Address

Token, ALI details)

E9-1-1 Tandem

SRDB gets routing information from Network LIS in real time. Assume that shell records for Address Tokens pre-populated in ALI DBs; ALI queries Network LIS using CBN, and retrieves ALI details from Network LIS in real time.

Originating Network

LAN

VoIP device

Local LIS

Local VoIP CMF


14

CAS-like Solution; CBN & Location Info with Call

IP device gets location

Emer-gency

call origina-

tion

SRDBALI DB

PSAP

Call setup (Caller ID, opt: ELIN or Location Object)

VoIP Call setup (CBN

& ELIN/Location Object)

Routing Query (ELIN/CGL)

Call setup (CBN & ELIN)

Query (CBN, ELIN)

Response (CBN & ALI)

Response (ESN or equiv.)

api (Caller ID)

api (ELIN/

Location Object)

VoIP Gwy

GR-3023 ISDN PRI SETUP

(CBN & ELIN or CGL)

NOTE: To be specified; may leverage IETF Geopriv & other WG

solutions?

* Queries assume that ELIN/CGLs pre-populated with ESN in SRDB & location information in ALI DB during service order or by Network LIS during address validation processes.

E9-1-1 TandemOriginating

Network

VoIP device

Local LIS

Local VoIP CMF

NOTE: Optional query if device doesn’t know

location


15

Pure VoIP Solution

IP device gets

location

Emer-gency

call origina-

tion

VoIPPSAP

VoIP Call setup (Caller ID,

Location Object =lat/long and/or Civic Location)

VoIP Call setup (Caller ID &

Location Object)

VoIP’ Call setup (Caller ID &

Location Object)

VoIP’ Call setup (Caller ID &

Location Object)

VoIP Gwy

NOTE: To be specified; should leverage IETF Geopriv

& other standard WG solutions

Selective Routing Function

Originating Network

VoIP device

Local LIS

Local VoIP CMF VoIP E9-1-1

NetworkDHCP

NOTE: may not be needed if routing to PSAP determined at originating network?Coordinate-based routing? Impractical to decode civil location for routing.


16

Next Steps

Definition of VoIP protocols to carry lat/long and civic location (interworking issues with PSTN for CGL)– Leverage IETF Geopriv and DHCP work

Specification of Local LIS to Network LIS protocols for address validation and creation/updates (leverage NENA XML library)

Specification of DHCP Server to Local LIS function interface Specification of Local LIS function/application

– Telcordia plans to issue Generic Requirements later this year for some Local LIS applications

Documents

Alternatives for Providing Routing and Location Information