WiMAX Network Architecture and Emergency - Status Update – 7th Emergency Services Workshop College Park, MD, USA May 2010 Contact: Nokia Siemens Thanks to Greg Schumacher and Ming Lai for additional input!

WiMAX Forum Standards Activities ●The WiMAX Forum ( developswww.wimaxforum.org ●Requirements in the Service Provider WG (SPWG) ●A standardized network architecture ●in the Network WG (NWG) ●where most emergency efforts take place ●Radio interface profiles ● in the Technical WG (TWG) ●based on IEEE and m

Releases of the WiMAX network standards ●Release 1.0 published in 2007 ●Release 1.5 published in 2009 ●many enhancements, some new features ●Emergency support: citizen-to-authority, focused on emergency access ●IMS support: 3GPP IMS with WiMAX-specific discovery, Policy and Charging Control (PCC) support ●Standardized Location support ●Detailed presentation from ES-Workshop05 (Vienna, 2008): coordination.info/2008Oct/slides/esw5-wimax.pdf coordination.info/2008Oct/slides/esw5-wimax.pdf

Releases of the WiMAX network standards ●Release 1.6 (under final review, will be published during 2010) ●introduces network-initiated priority treatment for Emergency Telecommunications Service (ETS) ●Release 2.0 (specification development started recently) ●enhancements to emergency call support and ETS planned ●References for Release 1.5: ●Core Specification (stage-3): /WMF-T R015v01_Network-Stage3-Base.pdf /WMF-T R015v01_Network-Stage3-Base.pdf ●Emergency Services Support: /WMF-T R015v02_Emergency-Services.pdf /WMF-T R015v02_Emergency-Services.pdf ●Location based Services (LBS): /WMF-T R015v01_LBS.pdf /WMF-T R015v01_LBS.pdf

ES Roaming Reference Architecture

ES network entry overview ●The ES specification ( WMF-T R015 ) focuses on network access WMF-T R015 ●Placing an emergency call while already on the network is handled by the VoIP application (separate spec like for IMS) ●WiMAX uses EAP/AAA-based network entry ●EAP = Extensible Authentication Protocol, IETF RFC 3748 ●Access security and authorization via EAP methods ●Set up quality-of-service profiles with RADIUS/Diameter ●Network (visited CSN) selection supported via NAI decoration ●Emergency is indicated through NAI decoration ●NAI = network access identifier, IETF RFC 4282 ●NAI carries the user identity of the subscriber within EAP/AAA indicates emergency ●No impact or dependency on e MAC layer

Unauthorized/Unauthenticated Support in WiMAX ES ●Unauthorized = empty prepaid, barred subscription, roaming not allowed, etc. ●mainly depending on home operator (AAA-server) policy ●possible in WiMAX to grant limited access for unauthorized cases ●emergency is recognized during network entry, further handling depends on operator policy ●Unauthenticated = no subscription or unrecognized subscription ●All WiMAX devices are shipped with a device certificate ●Public-key infrastructure required for certificate verification hosted by the WiMAX Forum, see ●If no (user) subscription is available, network entry for emergency can be allowed with ●using EAP-TLS as authentication method ●providing the device certificate in EAP-TLS to the network ●This simply provides an appropriate building block. Operators can enable this, if required.

ETS support in WiMAX ●ETS = Emergency Telecommunications Service (authority-to-authority) ●Release 1.6 only provides an initial specification that allows ETS priority signaling within the WiMAX network ●No specific considerations for the radio interface ●Specification is currently under final review. ●Will be published as part of the final Release 1.6 core specifications later in ●Opens (planned to be addressed by Release 2.0): ●Exact method to signal ETS and priority across the radio interface (needs harmonization of all existing emergency fields in the wireless MAC layer (L2 of and m) ●Detailed structure of the Priority Indication field for ETS and other emergency services (considered out-of-scope in Release 1.6)

Emergency enhancements planned for Release 2.0 networks ●Consider radio link emergency signaling ●Current network specification only uses EAP NAI decoration for emergency call indication. Works fine in network entry, but difficult when the device is already attached to the network. ●IEEE and m provide an emergency indication as part of the initial ranging message. ● and m also define several emergency related TLVs. Unclear how to use them in the network. ●Update specification text to better match local regulation (in particular for the North-America region). ●Improve support for dedicated VoIP systems. ●Support for broadcast messaging and CMAS (commercial mobile alert system) specific extensions discussed at requirements level

Comments welcome!