Dynamic E911

Dynamic E911 delivers location information to PSAPs during emergency calls. Two methods available:

Method	Use case	Location source
API-based addresses	Fixed locations (offices, buildings)	Pre-provisioned via API
GPS coordinates	Mobile devices, wearables, IoT	PIDF-LO in SIP INVITE

API-based addresses

Pre-provision addresses and endpoints, then reference IDs in SIP headers during calls.

Create emergency address

POST /v2/dynamic_emergency_addresses

{
  "house_number": "1901",
  "street_pre_directional": "W",
  "street_name": "MADISON",
  "street_suffix": "ST",
  "locality": "CHICAGO",
  "administrative_area": "IL",
  "postal_code": "60612",
  "country_code": "US"
}

Response includes:

• id - Address UUID for endpoint association
• sip_geolocation_id - Include in Geolocation header
• status - pending during validation, activated when ready

Create emergency endpoint

POST /v2/dynamic_emergency_endpoints

{
  "dynamic_emergency_address_id": "uuid-from-address",
  "callback_number": "[phone]",
  "caller_name": "Jane Doe"
}

Response includes:

• sip_from_id - Include in From or P-Asserted-Identity header

SIP INVITE format

Include both IDs in emergency call INVITE:

INVITE sip:[e-mail] SIP/2.0
From: <sip:{sip_from_id}@origin.example.com>
To: <sip:[e-mail]>
Geolocation: {sip_geolocation_id}

Alternative using P-Asserted-Identity:

P-Asserted-Identity: <sip:{sip_from_id}@origin.example.com>
Geolocation: {sip_geolocation_id}

GPS coordinates (PIDF-LO)

Pass real-time coordinates in PIDF-LO format for mobile devices, wearables, and IoT.

Coordinate format

Parameter	Range	Notes
Latitude	-90 to +90	Negative = South
Longitude	-180 to +180	Negative = West
Precision	6-8 decimal places	Meter-level accuracy

SIP INVITE with PIDF-LO

INVITE sip:[e-mail] SIP/2.0
From: <sip:[e-mail]>
To: <sip:[e-mail]>
Geolocation: <cid:[e-mail]>
Content-Type: multipart/mixed;boundary=boundary1

--boundary1
Content-Type: application/sdp

[SDP content]

--boundary1
Content-Type: application/pidf+xml
Content-ID: <[e-mail]>

<?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf"
          xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10"
          xmlns:gml="http://www.opengis.net/gml"
          xmlns:dm="urn:ietf:params:xml:ns:pidf:data-model"
          entity="sip:[e-mail]">
  <dm:device id="device-001">
    <gp:geopriv>
      <gp:location-info>
        <gml:Point srsName="urn:ogc:def:crs:EPSG::4326">
          <gml:pos>41.8781 -87.6298</gml:pos>
        </gml:Point>
      </gp:location-info>
      <gp:usage-rules>
        <gp:retransmission-allowed>false</gp:retransmission-allowed>
      </gp:usage-rules>
    </gp:geopriv>
    <dm:timestamp>2024-01-15T10:30:00Z</dm:timestamp>
  </dm:device>
</presence>

--boundary1--

PIDF-LO requirements

Element	Requirement
<gml:pos>	Latitude then longitude, space-separated
srsName	Must be urn:ogc:def:crs:EPSG::4326
<dm:timestamp>	ISO 8601 format

Testing

Use test number 933 to simulate emergency calls without dispatching services.

Address field limits

Field	Required	Max Length	PIDF-LO Element
house_number	No	6	HNO
house_suffix	No	45	HNS
street_pre_directional	No	2	PRD
street_name	Yes	200	RD
street_suffix	No	45	STS
street_post_directional	No	2	POD
extended_address	No	60*	LOC
locality	Yes	100	A3
administrative_area	Yes	2	A1
postal_code	Yes	10	PC
country_code	Yes	2	country
caller_name	No	50	-

*Common terms auto-abbreviated: APARTMENT→APT, FLOOR→FL, SUITE→STE, BUILDING→BLDG, ROOM→RM