Table 16.1 Types of Location Information
TYPE EXAMPLE
Civic Country, state, city, street address and floor, appartment, or
cube.
Postal Similar to the civic address but the post office box (P.O.B.) or
building may not reveal the actual location.
Geospacial The longitude, latitude, and altitude information.
Cell Tower/Sector Cell tower ID and antenna used by the mobile device. The
mobile country code and mobile network code may also be
provided.An Internet-centric approach using the DNS and its design philosophy of
delegation has been outlined in [1]. The emergency call information in the
DNS is based on the Dynamic Discovery and Delegation System using the
DNS as specified in RFC 3761. We will illustrate here the main characteristics
to explain how the DNS-based Internet emergency calling information works:
■■ The top-level domain is defined as sos.arpa, where sosstands for
emergency calls.
■■ The country code is added to the left and the administration is dele-
gated to the country domain, such us.sos.arpa.
■■ Province or state domains, counties, cities, and street addresses are
added further to the left and their administration is delegated further
down so as to create a delegation tree, similar to those described in
Chapter 4, “DNS and ENUM.”
The administrator of any entity can contract the maintenance of the DNS
entries with a DNS registrar of their choice. This is similar to the DNS and
ENUM registrars discussed in Chapter 4.
Table 16.2 shows an example of a delegation tree for the root domain sos
.arpa.Table 16.2 Example for Delegation in the SOS DNS Tree for Location Information
DELEGATION
TREE BRANCH ADDRESS
Root for SOS sos.arpa
Country us.sos.arpa
State/Province pa.us.sos.arpa
County allegheny.pa.us.sos.arpa
City pittsburg.allegheny.pa.us.sos.arpa276 Chapter 16