IP Location

Introduction

Figure 1: Logical network location versus geographic location.

Figure 2: The standard Earth geoid, as defined in WGS 84.

Chapter 1: A Brief History of Location Services and Concepts

Figure 1.1: A vertical fleet application showing vehicle GPS, network, and application server.

Figure 1.2: Adding the "You are here" to Internet applications.

Figure 1.3: ANI-ALI in the emergency network-a wireline phone lookup.

Figure 1.4: Atypical GSM cellular network emergency service architecture.

Figure 1.5: Location technologies in cellular networks.

Figure 1.6: TA breakdown

Figure 1.7: Uncertainty expressed as different shapes.

Figure 1.8: Non-linear location/confidence relationship.

Figure 1.9: Obtaining an area of uncertainty at a specific confidence level.

Figure 1.10: FCC-prescribed cellular uncertainty and confidence.

Figure 1.11: The NENA i2 architecture.

Figure 1.12: Spoofing a location in an emergency call.

Figure 1.13: Location architecture functional layers.

Figure 1.14: The LIS centralized architecture.

Chapter 2: Location, Presence, and Privacy

Figure 2.1: The presence model.

Figure 2.2: The GEOPRIV abstract model.

Figure 2.3: GEOPRIV roles in i2-location by-reference.

Figure 2.4: A generalized location by-reference configuration.

Figure 2.5: GEOPRIV roles in i2-location by-value.

Figure 2.6: GEOPRIV roles in i2-location by-value.

Figure 2.7: Shapes for the representation of uncertainty in PIDF-LO.

Figure 2.8: An ellipse is a two-dimensional conical section.

Figure 2.9: The ellipsoid shape adds a third dimension by including a height parameter.

Figure 2.10: A prism is useful in representing a floor of a building.

Figure 2.11: An arc-band shape and its defining parameters.

Figure 2.12: The structure of a common-policy document.

Figure 2.13: Delegating the evaluation of privacy rules in 3GPP.

Chapter 3: Location Determination and the Access Location Entity

Figure 3.1: Different types of ALEs for different access networks.

Figure 3.2: ALEs in the GSM access network (GERAN).

Figure 3.3: Location measurements are combined with a database to determine location.

Figure 3.4: An ALE sends a Notification message to indicate a change in the network.

Figure 3.5: A Resynchronization Request triggers multiple Resynchronization Responses.

Figure 3.6: An Access Query is the synchronous method for retrieving ALE data.

Chapter 4: The LIS, Location Acquisition, and the HELD Protocol

Figure 4.1: LIS to GEOPRIV mapping.

Figure 4.2: The location by-value model.

Figure 4.3: The location by-reference model.

Figure 4.4: Location type negotiations.

Figure 4.5: Basic LIS interfaces.

Figure 4.6: An unqualified location request.

Figure 4.7: A qualified location request.

Figure 4.8: HELD context creation messaging.

Figure 4.9: HELD context lifeTime and LocationURI usage.

Figure 4.10: Location assertion using HELD.

Figure 4.11: An external IP address discovery problem.

Figure 4.12: Learning an externally routable IP address via STUN.

Figure 4.13: DNS SRV LIS discovery.

Figure 4.14: A Gateway LIS configuration.

Figure 4.15: A Proxy LIS configuration.

Figure 4.16: The Proxy-Gateway LIS.

Chapter 5: IP Location in Enterprise Networks

Figure 5.1: Wired Ethernet.

Figure 5.2: A basic WiFi network.

Figure 5.3: A wireless network controller network.

Figure 5.4: An SNMP bridge MIB ALE.

Figure 5.5: LIS static provisioning.

Figure 5.6: ARP table polling.

Figure 5.7: DHCP-assisted IP-to-MAC binding.

Figure 5.8: DHCP Lease Query ALE.

Figure 5.9: A DHCP relay in the core network.

Figure 5.10: A DHCP relay in the edge switch.

Figure 5.11: A DHCP Lease Query ALE extension.

Figure 5.12: PABX on-behalf-of location request.

Figure 5.13: An LLDP-MED Class III device network.

Figure 5.14: DHCP location acquisition.

Figure 5.15: A HELD location request.

Figure 5.16: A HELD on-behalf-of location request.

Figure 5.17: A Gateway LIS operating as a relay.

Figure 5.18: A client-based locator sequence diagram.

Figure 5.19: A DNS dynamic update.

Figure 5.20: Asset and staff tracking configuration.

Figure 5.21: Emergency routing with a literal location.

Figure 5.22: Emergency routing with an explicit location URI.

Figure 5.23: Emergency routing with an implicit location reference.

Chapter 6: IP Location in Wireline Public Carrier Networks

Figure 6.1: Basic DSL deployment.

Figure 6.2: DSL access entities.

Figure 6.3: DSL segments.

Figure 6.4: U-Interface protocol stacks.

Figure 6.5: A10-interface protocol stacks.

Figure 6.6: PPP data encapsulation.

Figure 6.7: PPPoE PADI message with TAG.

Figure 6.8: PPPoE data encapsulation.

Figure 6.9: L2TP network architecture.

Figure 6.10: A generic DSL LIS configuration.

Figure 6.11: IP routing over the A10-Interface using ATM and RADIUS.

Figure 6.12: Switch and RANP-LIS provisioning.

Figure 6.13: A session establishment and measurement collection.

Figure 6.14: Requesting location.

Figure 6.15: ATM layer 2 over the service provider segment.

Figure 6.16: ATM layer-2 service provider segment location acquisition.

Figure 6.17: 1-1 VLAN forwarding on service provider segment.

Figure 6.18: Dual-tagged VLAN on a service provider segment location acquisition.

Figure 6.19: N-1 VLAN forwarding.

Figure 6.20: N-1 VLAN forwarding message flow.

Figure 6.21: PPPoE intermediary circuit tag.

Figure 6.22: N-1 VLAN layer-2 forwarding using DHCP.

Figure 6.23: L2TP over the service provider segment.

Figure 6.24: Data flow for L2TP over the service provider segment.

Figure 6.25: A modern cable network configuration.

Figure 6.26: A cable network MAC frame.

Figure 6.27: Cable Internet configuration.

Figure 6.28: Cable Internet location configuration.

Figure 6.29: Cable network location acquisition.

Chapter 7: WiFi and Ad Hoc Wireless Networks

Figure 7.1: An infrastructure WLAN relies on access points.

Figure 7.2: Participants in an ad hoc network are active in routing messages.

Figure 7.3: Determining the distance between two transceivers.

Figure 7.4: Using trilateration in two dimensions from three access points.

Figure 7.5: A directional antenna can be used like a radar system to determine a direction.

Figure 7.6: Time difference of arrival measurements used to determine location.

Figure 7.7: Degradation of precision caused by multiple hops in an ad hoc network.

Figure 7.8: The final precision is greatly affected by the precision at each hop.

Figure 7.9: Using multiple paths to refine a location estimate.

Figure 7.10: A LIS can use infrastructure (access points) to acquire location measurements.

Figure 7.11: IP mobility allows changes in an IP address by tunneling messages.

Chapter 8: IP Location in Wireless Public Carrier Networks

Figure 8.1: Packet data location architecture.

Figure 8.2: The GPRS architecture.

Figure 8.3: The LIS in a GPRS network.

Figure 8.4: Mobile IP architecture.

Figure 8.5: The 1xEVDO network.

Figure 8.6: A LIS in the 1xEVDO network.

Figure 8.7: A UMA in a GSM network.

Figure 8.8: A UMA using LIS functionality.

Figure 8.9: WiMAX as a wired broadband alternative.

Figure 8.10: An access network conundrum.

Figure 8.11: Wireless access location solution.

Figure 8.12: The basic IMS architecture.

Figure 8.13: An integrated location solution.

Chapter 9: Device Interactions in Location Determination

Figure 9.1: Device roles in completely independent operation.

Figure 9.2: An independent device is able to use a presence service to simplify its role.

Figure 9.3: Delegating the responsibility for credentialed location to the LIS.

Figure 9.4: The LIS can be used to provide publicly accessible location URIs.

Figure 9.5: The LIS could cache location information for later use.

Figure 9.6: The LIS uses a callback to access device-based information on demand.

Figure 9.7: A capabilities indication is made so the device can be updated as circumstances change.

Figure 9.8: An LLDP-capable device can provide measurements using SNMP.

Figure 9.9: A device that can read RFID tags can provide those codes as measurements.

Figure 9.10: Device-assisted A-GNSS using SUPL messaging that directly involves the LIS.

Chapter 10: Privacy Considerations for Internet Location

Figure 10.1: Two privacy principles from the Australian Privacy Act of 1988.

Figure 10.2: Privacy control in a 3GPP GSM network.

Figure 10.3: The LIS assumes many of the privacy roles in this architecture.

Figure 10.4: To simplify rule management, an external service can host privacy preferences.

Figure 10.5: The LIS can use a PPR to delegate the evaluation of privacy rules.

Figure 10.6: A presence service assumes much of the responsibility for controlling privacy.

Figure 10.7: The i2 emergency impact on the presence privacy architecture.

Appendix A: Abridged Flap Specification

Figure A.1: A high-level message schema UML.