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ESW – May 2010. UK Architecture for VoIP 999/112s John Medland – BT 999/112 Policy Manager. UK Emergency Service . Public Emergency numbers - 999/112, - 18000 (ITU v21 text over voice, ie real time text using special terminals). Police 52%. Stage 1 PSAPs BT (5) or C&W (2).
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ESW – May 2010 UK Architecture for VoIP 999/112s John Medland – BT 999/112 Policy Manager
UK Emergency Service Public Emergency numbers - 999/112, - 18000 (ITU v21 text over voice, ie real time text using special terminals) Police 52% Stage 1 PSAPs BT (5) or C&W (2) Ambulance42% • Around 60% are connected to Stage 2 PSAPs (usually within 10 seconds) BT or CW Public Network Public networks • 31 million calls each year to stage 1 PSAPs, 55% from mobile phones Fire 6% 999/112/ 18000 Coastguard <1% Fixed/MobileNetworks (204 Local Controls) ( 999/112/18000
Location for emergency callers • Available automatically on fixed and mobile calls at Stage 1 and Stage 2 PSAPs • Fixed lines : civic locations as name and address updated daily to Stage 1 PSAP database • Mobile networks provide cell coverage area (enhanced with timing advance for some) over standard ETSI interface: radius ~2.2km • Limitations for VoIP calls, calls from private networks, mobile roamers • Stage 1 PSAPs provide Location Servers which can be accessed by Stage 2 PSAPs ( location retrieved instantly using telephone number + secure TCP/IP link) • Industry funded Stage 1 PSAPs supply location free to Stage 2 PSAPs (Stage 2 PSAPs pay for their lines, hardware and software) • Telematics emergency calls (non-standard eCalls) growing and can provide GPS information
Handling VoIP 999 now • PSAPs still TDM based so VoIP goes through PSTN / IP Gateways • Small number of VoIP 999s at present, mostly fixed users • Regulation says if PSTN access, then must allow 999 • 999s identified as VoIP • Registered “default” address accessed through E164 tel number (CLI) for “fixed” users…. • ….but default address marked as needing voice confirmation Verbal routing • Device/CPE use PSTN/GSM for 999 if possible • Key issues for VoIP 999 : -- only default name+address data from large number of VoIP SPs- challenge of 24 hour VSP contact point for PSAP use (tracing, alternative contact numbers)- lack of information to PSAP for nomadic users • Need to Automate Location provision………
NICC Task Group • The Network Interoperabilty Consultative Committee : NICC is a UK telecommunications industry committee which acts as an industry consensus group in which specifications and technical issues associated with network competition can be discussed. It also is a source of technical advice to the UK Regulator • Location Task Group : Routing 999/112 for VoIP to correct local EA supplying caller location information on all calls • Membership : BT, C&W, Ericssons, Huawei, Andrew, Nominet, Magrathea, Aeonvista,Vodafone, VirginMedia, Orange, and Ofcom +…. • Approach :-- VSP, ISP and Access Provider(s) all different organisations- PSAPs are still TDM based- Start with UK only (all parties UK-based) - Cover DSL, Cable, Enterprise, WiFi and GSM scenarios - Use developing standards wherever possible, eg IETF, ETSI- Don’t rely on user- Don’t rely on device
VoIP call VSP 1 Soft-Switch SBC1 1 SBC2 SBC1/2 VSP 2 soft switch (Aggregation + SS7 interconnect ) Access and IP Log-on functions a 2 PIG Source IP+Port, VSP 1 ID and CLI information(NENA v2) CLI + VSP1 id Internet service & access infrastructure providers PSTN—IP Gateway VPC b CLI + VSP1 id IAIC 3 ISP LIS c 4 Emergency Handling Authority –Stage 1 PSAP Request using CLI, VSP id.Response gives location Key Overview of Architecture and Interfaces LIS URI IP HELD third party request using Source IP (+ Port no.), in HELD ID extensions. Response gives PIDF-LO Voice path Data path
VSP Soft Switch Interface (a)Key Parameters (CLI,Source Public IP Address, source port number) Interface ( b)Parameter (Source Public IP Address) IAIC (IP Address to ISP Converter) VoIP Positioning Centre Interface ( c )Parameter (Source Public IP Address) Inteface(b)Parameter (ISP LIS URI) Interface (4)Parameter (CLI) Interface (4)Parameter(Location) Interface( c )Parameter (PIDF-LO Location) ISP LIS Emergency Handling Agency VPC Functions
IAIC IP / AS mapping BGP4 Route Collector IP Address BGP Route Updates BGP Peers Interface (b) AS / LIS mapping LIS URI VPC - Mapping Source IP address to ISP
Interface (c) LIS HELD Server iM1 iB1 LIS OSS Systems IP@ translation; Border Functions - NAPT/SBC/ALG iC1 iL2 Network elements Other LIS Generic LIS Functions
Way Forward for UK • NICC Standard published Jan 2010 http://www.niccstandards.org.uk/files/current/ND1638%20V1.1.2.pdf?type=pdf • New requirements on all organisations (systems development) • Many more organisations involved to deliver 999 (not just traditional telcos but VSPs and ISPs) • New operational components : LIS and VPC • New interfaces for all organisations: based on international standards as far as possible (eg IETF HELD) • Increased co-op and trust relationships between PSAP and VSP, ISP and Access networks • NICC Work to continue : other use cases, IP PSAPs (IP end to end)