Reviewers (PMD-2506):

User Story

As a CSP that provides the services in Europe and/or North America we forced by the government to introduce NG112 and/or NG911 technologies and standardize way of providing emergency communications to our customers whether it's some calling app (like MS Teams or Zoom, etc) or a regular user agent. To do that we need:

  • record, keep, update and remove emergency address and location for the customer;
  • include customer location information to the SIP header of the emergency call to locate the caller:
  • track customer location information if it's changes dynamically (mobile only?);

Example of use

Here we can consider 3 examples depending on what is added to the SIP header, the PIDF-LO, Geo Location in SDP, Geo Location based on rfc8787:.

  1. A user is making an emergency call to 911 using a VoIP phone. The VoIP phone sends a SIP INVITE message to the emergency services network, which includes the PIDF-LO in the SIP header. The PIDF-LO contains the user's location information, including the latitude, longitude, altitude or civic address. The SIP header should include PIDF-LO with geospatial address or "CivicAddress", below there are the examples of both : 

    PIDF-LO includes geospatial address
    INVITE sip:911@emergency-services-network.com SIP/2.0
Via: SIP/2.0/TCP pc33.example.com;branch=z9hG4bK776asdhds
Max-Forwards: 70
From: sip:joe@example.com;tag=4321
To: sip:911@emergency-services-network.com
Call-ID: 1234567890@pc33.example.com
CSeq: 1 INVITE
Contact: sip:joe@pc33.example.com
Content-Type: application/sdp
User-Agent: Example SIP Client
Allow: INVITE, ACK, CANCEL, BYE
Content-Length: 168

P-Asserted-Identity: sip:joe@example.com
Privacy: none

P-Early-Media: Supported

PIDF-LO: <?xml version="1.0"?>
<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:gs="http://www.opengis.net/pidflo/1.0">
  <tuple id="t1">
    <status>
      <gp:geopriv>
        <gp:location-info>
          <gml:Point srsName="urn:ogc:def:crs:EPSG::4326">
            <gml:pos>42.3601 -71.0589</gml:pos>
          </gml:Point>
        </gp:location-info>
        <gp:usage-rules>
          <gp:retention-expiry>2008-06-05T22:00:00Z</gp:retention-expiry>
          <gp:retention-period>604800</gp:retention-period>
        </gp:usage-rules>
      </gp:geopriv>
    </status>
    <timestamp>2008-05-22T16:01:56Z</timestamp>
  </tuple>
</presence>
    PIDF-LO includes "CivicAddress"
    SIP/2.0 200 OK
Via: SIP/2.0/UDP 192.0.2.101:5060;branch=z9hG4bKb6b7c5d3
From: "Alice" <sip:alice@example.com>;tag=1928301774
To: "Bob" <sip:bob@example.com>;tag=a6c85cf
Call-ID: a84b4c76e66710
CSeq: 314159 INVITE
Contact: <sip:bob@192.0.2.4>
Content-Type: application/pidf+xml

<?xml version="1.0" encoding="UTF-8"?>
<pidf xmlns="urn:ietf:params:xml:ns:pidf"
      xmlns:geopriv="urn:ietf:params:xml:ns:pidf:geopriv10"
      xmlns:gml="http://www.opengis.net/gml"
      xmlns:rpid="urn:ietf:params:xml:ns:pidf:rpid"
      xmlns:cp="urn:ietf:params:xml:ns:pidf:cipid"
      entity="sip:bob@example.com">
  <status>
    <basic>open</basic>
  </status>
  <geopriv:location-info>
    <geopriv:civicAddress>
      <geopriv:street>123 Main St</geopriv:street>
      <geopriv:city>Anytown</geopriv:city>
      <geopriv:state>CA</geopriv:state>
      <geopriv:postalCode>12345</geopriv:postalCode>
    </geopriv:civicAddress>
  </geopriv:location-info>
</pidf>

  2. A user is making an emergency call to 911 using a VoIP phone. The VoIP phone sends a SIP INVITE message to the emergency services network. The SIP header includes the Geo location ("a=geo" field). The a=geo field in the SIP message is intended to convey only the latitude and longitude coordinates of the endpoint's location. It does not include any additional location information, such as a civic address or altitude. The example is below:

    "a-geo" field includes Geo location information in SDP
    INVITE sip:alice@example.com SIP/2.0
Via: SIP/2.0/TCP pc33.example.com;branch=z9hG4bK776asdhds
Max-Forwards: 70
From: Bob <sip:bob@example.com>;tag=1827n
To: Alice <sip:alice@example.com>
Call-ID: 4872a7sdasdhds@pc33.example.com
CSeq: 1 INVITE
Contact: <sip:bob@pc33.example.com>
Content-Type: application/sdp
Content-Length: 142
User-Agent: My SIP Client/1.0

v=0
o=bob 2890844526 2890844526 IN IP4 pc33.example.com
s=Session SDP
c=IN IP4 192.0.2.20
t=0 0
m=audio 49170 RTP/AVP 0
a=rtpmap:0 PCMU/8000
a=geo:40.748817,-73.985428
  3. RFC 8787 based example:
Geolocation header RFC 8787 (in trust domain)
   INVITE sip:bob@biloxi.example.com SIP/2.0
   Via: SIP/2.0/TLS pc33.atlanta.example.com;branch=z9hG4bK74bf9
   Max-Forwards: 70
   To: Bob <sip:bob@biloxi.example.com>
   From: Alice <sip:alice@atlanta.example.com>;tag=9fxced76sl
   Call-ID: 3848276298220188511@atlanta.example.com
   Geolocation: <cid:target123@atlanta.example.com>,
        <https://lis.example.com:8222/y77syc7cuecbh>;
                 loc-src=edgeproxy.example.com
   Geolocation-Routing: yes
   Accept: application/sdp, application/pidf+xml
   CSeq: 31862 INVITE

Technology

NG112, NG911

Definitions, acronyms and abbreviation

AbbreviationDescription
CSPCommunication Service Provider
PSAPPublic safety answering points.  It is a facility that is responsible for answering emergency calls and dispatching emergency services in a particular geographic area. PSAPs are typically staffed by trained personnel who are responsible for handling emergency calls from the public and coordinating the dispatch of emergency services such as police, fire, and medical personnel.
PIDF-LOPresence Information Data Format Location Object. It is a data format used to represent the location of a user or device in real-time communication systems, such as Voice over IP (VoIP) or Instant Messaging (IM).
NG112

Next Generation 112 (NG112) is an initiative in Europe that aims to improve emergency communication service. 

NG112 integrates voice, video, text, and location data to enhance emergency response and enable citizens to communicate with emergency services through various means.

NG112 builds upon the existing emergency number in Europe, which is 112.

NG911

Next Generation 911 (NG911) is an initiative in the United States that aims to upgrade the existing emergency response systems to a digital, IP-based infrastructure. NG911 focuses on enhancing the capabilities of emergency communication centers (PSAPs) by enabling the transmission of multimedia information, such as text messages, photos, and videos, alongside traditional voice calls.

NG911 builds upon the existing emergency number in the United States and Canada, which is 911.

EENA

European Emergency Number Association ( NG112)

NENANational Emergency Number Association  (NG911)
ESRPEmergency service routing protocol
LISLocation Information Server
Geospatial addressA physical address that has been standardized and encoded in a way that allows it to be used in geospatial systems. A geospatial address typically consists of a number of components, including a street name and number, a city or town name, a province or state name, and a postal code or zip code.

Current Solution

In PortaSwitch, a special emergency module performs emergency call handling. The user location information is not included in the SIP header.

Stakeholders and their benefits

Benefit /
Stakeholders		Improved emergency serviceEENA and NENA complianceImproved emergency call routing
CSPs✓✓✓
End user✓

CSPs will be able to provide emergency services equally accessible to all citizens from any communications devices with exact customers location, that improves call routing. That's in result, facilitate further connection of the public safety points and the customer enhancing the overall emergency response effectiveness. 

Also CSPs will comply with Europe and North America government policies in providing emergency services.

The CSP's customers will be able to access emergency services from any device or application they use:

  • make an emergency call from any device or application like zoom or MS Teams;
  • use emergency services via the media sources, such as video calls, passing of attached data from chats to PSAPs .

Thus having the improved emergency service experience and more chances to be saved on time in the critical situation.

Research findings

QuestionAnswer
Where do CSPs get/gather information about the emergency location of the user?CSPs ask their customers (they can be end users or the admins of the enterprises) to define the locations by themselves and update it periodically.
Where can CSPs obtain the geospatial address?

  1. GPS coordinates: If the user's device has GPS capability, the service provider can obtain the location information directly from the device.

  2. Cell tower triangulation: If the user's device does not have GPS capability, the service provider can use the location of nearby cell towers to estimate the user's location.

  3. Wi-Fi triangulation: Similar to cell tower triangulation, the service provider can use the location of nearby Wi-Fi access points to estimate the user's location.

  4. Civic address databases: Some service providers maintain databases of civic addresses (such as street addresses) and their corresponding geospatial coordinates. The service provider can use this information to convert a civic address into a geospatial address.

  5. User input: In some cases, the user may manually input their geospatial address into the system (such as in a profile or registration form).

What are possible formats of the geospatial address?

  1. Well-Known Text (WKT) format: This is a text-based format for describing geometries in geospatial systems. It can be used to represent point, line, and polygon geometries, and includes information about the spatial reference system (SRS) in which the geometry is defined.
    Example: POINT(-122.084, 37.422), it defines the point (where address located) with a longitude and latitude.

  2. Keyhole Markup Language (KML) format: This is an XML-based format developed by Google for describing geospatial data in Google Earth and other mapping applications. It can be used to represent points, lines, polygons, and other spatial features, as well as annotations, images, and other non-spatial data.
    Example:     This KML representation defines a placemark with the name "1600 Amphitheatre Parkway, Mountain View, CA, USA" and a point geometry specified by the coordinates -122.084 (longitude) and 37.422 (latitude).

    <?xml version="1.0" encoding="UTF-8"?>
    <kml xmlns="http://www.opengis.net/kml/2.2">
      <Placemark>
        <name>1600 Amphitheatre Parkway, Mountain View, CA, USA</name>
        <Point>
          <coordinates>-122.084,37.422</coordinates>
        </Point>
      </Placemark>
    </kml>

  3. GeoJSON format: This is a JSON-based format for encoding geospatial data. It can be used to represent points, lines, polygons, and other spatial features, and includes information about the coordinate reference system (CRS) in which the data is defined.
    Example:

    {

      "type": "Feature",

      "geometry": {

        "type": "Point",

        "coordinates": [-122.084, 37.422]

      },

      "properties": {

        "name": "1600 Amphitheatre Parkway, Mountain View, CA, USA"

      }

    }

  4. GeoRSS format: This is an XML-based format for encoding geospatial data in RSS feeds. It can be used to represent points, lines, polygons, and other spatial features, and includes information about the coordinate reference system (CRS) in which the data is defined.
    Example:     <georss:point>37.422 -122.084</georss:point>

  5. GML (Geography Markup Language) "urn:ogc:def:crs:EPSG::4326", which is the coordinate reference system used for WGS 84 (geodetic reference system that defines a coordinate system for representing locations on the Earth's surface).
What exactly PortaOne customers will need to send to the emergency service provider (Europe and North America specifics)?

PIDF-LO or Geo Location can be added to the SIP Header. The specific requirement may vary depending on the CSP. The PIDF-LO or Geo Location headers in the SIP header both provide location information for emergency services and other applications.

In general, PIDF-LO is more suitable for applications that require dynamic location information, such as emergency services, location-based services, and social networking. Geo Location header is more suitable for applications that require simple location information, such as call routing and traffic analysis. 

The pros and cons of each approach:

PIDF-LO:

Pros:

  • Supports rich and detailed location information, including altitude, floor, and civic address.
  • Can be updated dynamically as the user's location changes.
  • Can be easily integrated with other protocols, such as XMPP (Extensible Messaging and Presence Protocol).

Cons:

  • Requires more processing and overhead to encode and transmit the location information.
  • May be more complex to implement and support.


Geo Location:

Pros:

  • Simple and lightweight, with location information encoded directly in the SIP header.
  • Easier to implement and support compared to PIDF-LO.

Cons:

  • Supports only basic location information, such as latitude and longitude.
  • May not support updates to the location information.
  • May not be as interoperable with other protocols compared to PIDF-LO.

No information is found about what exactly is specific for Europe or North America, as it depends mostly on the CSP requirements and particular integration.

How do CSPs validate the emergency location of the user?
  • GoogleMaps could be used as a common database for the USA and Europe.
  • There are several geocode databases for location validation that are commonly used in the USA, including:
    1. Census Bureau's TIGER/Line: The TIGER/Line database is a free dataset provided by the US Census Bureau that includes address ranges and other geographic features for every address in the country. It is commonly used for population surveys, mapping, and demographic research.
    2. USPS Address Management System (AMS): The USPS Address Management System is a database that provides the most up-to-date information on addresses and ZIP codes in the US. It is commonly used for mail delivery, address verification, and marketing purposes.
    3. HERE Technologies: HERE Technologies provides geocoding data for the USA that is used by many businesses and organizations for mapping, logistics, and location-based services.
    4. Google Maps Platform: Google Maps Platform is widely used by businesses and consumers in the USA for mapping, navigation, and location-based services. It offers comprehensive geocoding services that can be integrated into applications.
    5. OpenStreetMap: OpenStreetMap is a free and open-source mapping platform that is widely used in the USA and other countries. It provides accurate geocoding data for addresses, points of interest, and other geographic features.
  • There are several geocode databases that are commonly used in Europe, including
    1. OpenStreetMap: OpenStreetMap is a free and open-source mapping platform that is widely used in Europe and other regions. It provides accurate geocoding data for addresses, points of interest, and other geographic features.
    2. TomTom Maps: TomTom Maps is a popular mapping platform that provides geocoding data for Europe and other regions. Its database covers over 200 countries and territories worldwide and provides accurate location data for various use cases.
    3. HERE Technologies: HERE Technologies provides geocoding data for Europe that is used by many businesses and organizations for mapping, logistics, and location-based services. Its geocoding services support both forward and reverse geocoding and provide accurate results worldwide.
    4. Google Maps Platform: Google Maps Platform is widely used in Europe and other regions for mapping, navigation, and location-based services. It offers comprehensive geocoding services that can be integrated into applications.
    5. IGN France: The French National Geographic Institute (IGN) provides geocoding data for France and other regions in Europe. Its database includes information on addresses, points of interest, and other geographic features.
How do other CSPs comply to NG emergency service provisioning?

In order not to show the names, the findings on emergency services deployments provided by different CSPs can be found here and here.