Location in SIP/IP Core (LOCSIP)

Transcription

1 in SIP/IP Core (LOCSIP) Conveyance with IMS: the OMA LOCSIP Service Enabler Don Lukacs Telcordia Applied Research 2010, Telcordia Technologies Inc.

2 in SIP/IP Core (LOCSIP) Topics General Background Material LOCSIP Objectives / General / Terminology Open Mobile Alliance (OMA) LOCSIP Enabler Release Package Overview of related documents LOCSIP status LOCSIP Technical Discussion General Capabilities Architecture Illustrative Flows Specific Capabilities supported in LOCSIP Specifications Conclusions / Next Steps 2

3 LOCSIP Objectives Create a service enabler to convey location information to applications via a SIP/IP core network (e.g., an IP Multimedia Subsystem [IMS]) Out-of-scope: Positioning determination functions May interwork with applicable positioning determination functions in access networks and/or in User Equipment Position determination functionality specified elsewhere (e.g., OMA Secure User Plane [SUPL]) Reuse capabilities in a SIP/IP core network, for location retrieval via a standardised SIP-based interface Benefit from existing functionality (e.g., registrations / security associations) in the SIP/IP core SIP Applications Servers can avoid additional interface types Synergy with other OMA enablers (e.g., Presence SIMPLE and PoC) that potentially use location information Apply available IETF (e.g., Geopriv) specifications SIMPLE: SIP for Instant Messaging and Presence Leveraging Extensions PoC: Push to talk Over Cellular 3

4 LOCSIP General / Terminology LOCSIP specifies how to use Session Initiation Protocol (SIP) to convey location information Server Server - Functional entity that handles location service subscription request and retrieves the location information of the Target. Messaging is based on SIP SUBSCRIBE / NOTIFY procedures SIP / IP Core 2 Out-of-scope for LOCSIP e.g., Secure User Plane (SUPL) Client 1 3 Target Client - Functional entity that subscribes to a Server in order to obtain location information for one or more Targets. 4 Target - The device or the user associated with a device whose location is requested.

5 Open Mobile Alliance (OMA) LOCSIP Status OMA (LOC) Working Group (WG) completed LOCSIP Enabler Release Package (ERP) as a Candidate Enabler in August 2009 ERELD - Enabler Release Definition RD Requirements Document AD Architecture Document TS - Technical Specifications 5

6 LOCSIP Requirements Document (RD) Candidate version: Permanent_documents/OMA-RD-LOCSIP-V1_ C.zip, in SIP/IP core Requirements, Candidate Version Aug 2009 LOCSIP RD defines four use cases (informative): Immediate Delivery Fetch current location (e.g., location-based charging) Periodic Delivery Obtain location updates periodically Illustrates reporting for group of Targets ( buddy list ) Area Trigger Delivery Report location updates if certain filter criteria satisfied (e.g., movement within or outside a certain geographic area) Find Friends Report location updates if a member of a secondary Target group moves within a certain distance from a primary Target Illustrates location request by Client in a Terminal 6

7 LOCSIP Requirements Document (RD) LOCSIP RD defines high-level functional requirements Examples: Support for Immediate, Periodic and Area Trigger Delivery Support filtering of location notifications (accuracy, response time, age) Support for Client in a SIP Application Server or in a terminal Client able to request location information for a group of Targets, based on referenced list or request-contained list Format of location information to be compliant with: [RFC4119] - Presence-based GEOPRIV Object Format [RFC5491] - GEOPRIV Presence Information Data Format Object (PIDF-LO) Usage Clarification, Considerations, and Recommendations [RFC5139] - Revised Civic Format for Presence Information Data Format Object (PIDF-LO) Additional requirements covering Security, Charging, Administration and Configuration, Privacy aspects, Emergency Services 7

8 LOCSIP Architecture Document (AD) Candidate version: manent_documents/oma-ad-locsip-v1_ c.zip, in SIP/IP core Architecture, Candidate Version Aug 2009 Key Contents: Defines Overall Architecture Defines Architectural Components and Interfaces / Reference Points Describes Flows Discusses Security Considerations 8

9 LOCSIP Architecture Document (AD) LOCSIP Reuse of Other OMA Enablers OMA Presence SIMPLE OMA XML Document Management (XDM) IMS in OMA Architecture Functional Components Client (LC) Server (LS) Home Subscription Agent Resource List Server (RLS) XDM Client (XDMC) XDM Server (XDMS) Shared List XDMS RLS XDMS Policy XDMS Global Permissions Management (GPM) SIMPLE: SIP for Instant Messaging and Presence Leveraging Extensions IMS: IP Multimedia Subsystem 9

10 LOCSIP Architecture Client LS-1 PRS-17 IP-1 Home Subscription Agent Remote SIP/IP Core PRS-4 Resource List Server PRS-10 PRS-9 Legend: Component specified by LOCSIP enabler SIP/IP Core XDM-2 RLS XDMS Shared List XDMS Policy XDMS Component not specified by LOCSIP enabler Reference point specified by LOCSIP enabler Reference point not specified by LOCSIP enabler Interface not specified by LOCSIP enabler XDM-12 LS-2 XDMC XDM-14 Trusted XDMC XDM Enabler Server GPM. PEM-1 Global Permissions Management 10

11 LOCSIP Architecture Client LS-1 PRS-17 IP-1 Home Subscription Agent Authorizes LC service use in LC s home domain Limits number of subscriptions for the LC Remote SIP/IP Core Subscribes to a Server in order to obtain location information for one or more Targets. Legend: Component specified by LOCSIP enabler Component not specified by LOCSIP enabler Reference point specified by LOCSIP enabler Reference point not specified by LOCSIP enabler Interface not specified by LOCSIP enabler SIP/IP Core Authorizes location subscription requests for the Target Retrieves location information and provides notifications PRS-4 XDM-2 XDM-12 LS-2 11 Resource List Server PRS-10 RLS XDMS XDM-14 Trusted XDMC PRS-9 Accepts and manages subscriptions to Group Lists Shared List XDMS XDM Enabler Server GPM. PEM-1 Policy XDMS Enables Client to subscribe to Information of multiple Targets XDMC using a single subscription transaction Global Permissions Management

12 LOCSIP Architecture Client LS-1 (Optional functional element ) PRS-17 Evaluates and processes permission rules. Returns a decision to the Server re: release of location information. PRS-4 IP-1 Home Subscription Agent Resource List Server PRS-10 XML Document Management (XDM) Server - manages Remote location policy documents SIP/IP Core (Subscription Authorization Rules / Privacy Rules) PRS-9 Legend: Component specified by LOCSIP enabler SIP/IP Core XDM-2 RLS XDMS Shared List XDMS Policy XDMS Component not specified by LOCSIP enabler Reference point specified by LOCSIP enabler Reference point not specified by LOCSIP enabler Interface not specified by LOCSIP enabler XML Document Management (XDM) Clients and Servers (XDMC / XDMS) XDM-12 LS-2 XDMC XDM-14 Trusted XDMC XDM Enabler Server GPM. PEM-1 Global Permissions Management 12

13 Immediate Delivery ( Fetch ) High-Level Flow Authorize Client s use of location service Limit number of subscriptions for the LC Forward request for location information Located in Home Domain of Client Home Subscription Agent 2 Fetch documents from XDMS Authorize Client s subscription to Target s location info Retrieve location information Generate notification Located in Home Domain of Target Server 3a Policy XDMS Global Permissions Management (GPM) SIP / IP Core 3b Out-of-scope for LOCSIP (e.g., SUPL) 1 4 Client Located in Home or Visited Domain Other (e.g., Visited) Domains Target Located in Home or Visited Domain 13

14 Immediate Delivery ( Fetch ) SIP Messaging Client LC SIP/IP Core Home Subscription Agent LS SIP/IP Core Server 1a. SUBSCRIBE 1b. SUBSCRIBE 2. Service Authorization 3a. SUBSCRIBE 3b. SUBSCRIBE 3c. SUBSCRIBE 4. Authorization 5b. 200 OK 5a. 200 OK 5e. 200 OK 5c. 200 OK 5d. 200OK 6. Retrieve Target and evaluate filter criteria 7. Enforce Policy 8b. NOTIFY 9a. 200 OK 8a. NOTIFY 9b. 200 OK 14

15 Immediate Delivery ( Fetch ) SIP Messaging (Potential IMS-based Realization) Client 1a. SUBSCRIBE Triggering in Home Network of Client: Use of ifc to cause S-CSCF to route SIP SUBSCRIBE to HSA Home P-CSCF S-CSCF Subsc. I-CSCF Agent 1b. SUBSCRIBE 1c. SUBSCRIBE 2. Service Authorization 3a. SUBSCRIBE 3b. SUBSCRIBE HSS SIP Application Server in Home Network of Client Cx: Information Query S-CSCF Server SIP Application Server in Target s Home Network 5f. 200 OK Use of ifc to cause S-CSCF to route SIP SUBSCRIBE to Server 5e. 200 OK 5d. 200 OK 5e. 200OK 5c. 200 OK 3c. SUBSCRIBE 5b. 200 OK 3d. SUBSCRIBE 5a. 200 OK 4. Authorization 6. Retrieve Target and evaluate filter criteria 7. Enforce Policy 8b. NOTIFY 8b. NOTIFY 8a. NOTIFY 9a. 200 OK 9a. 200 OK Based on: 3GPP TR , Section A b. 200 OK

16 Additional LOCSIP Capabilities LOCSIP supports additional extensions beyond Immediate Delivery: Periodic Delivery Server provides SIP NOTIFY messages (with updated location) periodically Area Trigger Delivery Server provides SIP NOTIFY message whenever Target s location satisfies filter criteria Retrieval for Multiple Targets Targets identified via referenced list or request-contained list 16

17 Retrieval Target List High-Level Flow Authorize Client s use of location service Limit number of subscriptions for the LC Forward request for location information Located in Home Domain of Client Home Subscription Agent Located in Home Domain of Target 5 Server Policy XDMS 4a Global Permissions Management (GPM) Fetch documents from XDMS Authorize Client s subscription to Targets locations Retrieve location information Generate notifications SIP / IP Core 4b 4b 1 Client Target Target Located in Home or Visited Domain Other (e.g., Visited) Domains Resource List Server Authorize Client s subscription to Target group list Perform back-end subscriptions on behalf of Client 3 Located in Home or Visited Domain Shared List XDMS RLS XDMS 17

18 LOCSIP Technical Specification (TS) Candidate version: nts/loc/permanent_documents/oma-ts-locsip-v1_ c.zip, in SIP/IP core Specification, Candidate Version Aug 2009 Contents include: Specifications for LOCSIP Functional Entities Specifications related to Security, Charging, and Registration Specifications for related (Information / Filter / QoS) documents 18

19 LOCSIP Technical Specification (TS) LOCSIP Capabilities Reuse of basic SIP SUBSCRIBE / NOTIFY Capabilities [RFC 3265] - Session Initiation Protocol (SIP)-Specific Event Notification [RFC 3856] - A Presence Event Package for the Session Initiation Protocol (SIP) LOCSIP extends above to support location conveyance Include feature tag in SIP SUBSCRIBE Distinguish location requests from Presence requests Allow proper routing to HSA and Server Use of Expires (=0) header to designate one-time location requests Specification of format for location information in body of SIP NOTIFY 19

20 Additional LOCSIP Capabilities Event Notification Rate Control Indicate the minimum / maximum time period between two consecutive notifications Request Information Satisfying Certain Criteria type (civic and/or geodetic) Maximum uncertainty Maximum response time Maximum age Required civic elements Specification of -Event Notification Filters Horizontal and vertical movement Enter or exit a particular region Speed Value Changes Relative positioning (inrange & outofrange) Conditional Event Notification Send event notifications only when state has changed since the previous notification Suppress entire notification message or the body of the location event notification Many of the above capabilities are based on IETF draft specifications: draft-ietf-sipcore-event-ratecontrol, draft-thomson-geopriv-location-quality, draft-ietf-geopriv-loc-filters, draft-ietf-sip-subnot-etags 20

21 Conclusions / Next Steps LOCSIP specifications have attained candidate enabler status (August 2009) Editorial comments and bug fixes applied in recent drafts Incorporation of updated IETF draft materials Upcoming LOCSIP efforts: Focus on Interoperability Testing Candidate LOCSIP Enabler Test Requirements (ETR): Permanent_documents/OMA-ETR-LOCSIP-V1_ C.zip, Enabler Test Requirements for in SIP/IP core, Candidate Version Aug 2009 Test Plans to be developed based on LOCSIP ETR material 21

22 Abbreviations 3GPP Third Generation Partnership Project 3GPP2 Third Generation Partnership Project AD Architecture Document AS Application Server CSCF Call Session Control Function ERELD Enabler Release Definition ERP Enabler Release Package ETR Enabler Test Requirements GEOPRIV Geographical / Privacy GML Geography Markup Language GPM Global Permissions Management HSA Home Subscription Agent HSS Home Subscriber Server I-CSCF Interrogating CSCF IETF Internet Engineering Task Force IMS IP Multimedia Subsystem LOCSIP in SIP/IP core LC Client LS Server OMA Open Mobile Alliance P-CSCF PEEM PEM-1 PIDF PIDF-LO PoC RD RLS S-CSCF SIMPLE SIP SUPL TS URI XDM XDMC XDMS XML Proxy CSCF Policy Evaluation, Enforcement and Management PEEM specified callable interface Presence Information Data Format Presence Information Data Format, Object Push to talk Over Cellular Requirements Document Resource List Server Serving CSCF SIP for Instant Messaging and Presence Leveraging Extensions Session Initiation Protocol Secure User Plane Technical Specifications Uniform Resource Identifier XML Document Management XDM Client XDM Server extensible Markup Language 22