Transcript document

Emergency Services
Workshop
UK “i2” for VoIP 999/112s
John Medland – BT 999/112 Policy Manager
UK Emergency Service today
(222 Local Controls)
Police 56%
BT or CW
Public TDM
Ntwk (PSTN)
BT or CW
Operator
Centres
Stage 1 PSAPs
Ambulance
35%
PSTN
Fire 8%
999/112/
18000
Other TDM
Networks
Coastguard
<1%
Stage 2 PSAPs
999/112/18000
BT – 28m calls, 55% mobile,
every call voice + location
Handling VoIP 999 now
•
•
•
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•
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 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, ALu, Huawei, Andrew, ETSI,
Magrathea, Thus, IN UK, Virgin Media, 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)
- Start with DSL, then tackle Cable, WiFI and GSM scenarios
- Use developing standards wherever possible, eg IETF, ETSI
- Don’t rely on user
- Don’t rely on device
Overview of Architecture and Interfaces
VoIP call
VSP 1
Soft-Switch
SBC1
1
SBC2
SBC1/2
VSP 2 soft switch
(Aggregation + SS7
interconnect )
2
CLI + VSP1 id
PSTN—IP
Gateway
PIG
a
Source IP+Port,
VSP 1 ID and CLI
information
(NENA v2)
LIS URI
Access
and IP
Log-on
functions
Internet service & access
infrastructure providers
IP
b
VPC
CLI + VSP1 id
3
IAIC
c
ISP LIS
4
Emergency
Handling
Authority –
Stage 1 PSAP
Key
Voice path
Data path
Request using CLI, VSP id.
Response gives location
HELD third party request
using Source IP (+ Port no.),
in HELD ID extensions.
Response gives PIDF-LO
Broadband and ADSL Access
User
Environment
Local Loop
Provider
Backhaul &
Aggregation
Provider
Internet Service
Provider
OSSLLP
OSSBAP
OSSISP
Emergency
Handling
Centre
Management
Control
RADIUS
Server
(RADIUS)
VPC
LIS
(RADIUS)
RADIUS
Server
(RADIUS)
(RADIUS)
Figure E1: xDSL Architecture for PPP Tunnelled via L2TP to ISP
L2TP Network
Server
L2TP Access
Concentrator
DSLAM
Residential
G/W
Voice
Terminal
Media
SIP
IP N/W
RTP/RTCP
Internet
Telephony
Service
Provider
L2TP
Network
Server
L2TP
Aggregation
Concentrator
DSLAM
Residential
G/W
BAP
RADIUS
Server
ISP
RADIUS
Server
L2TP Tunnel Establishment
PPP Link Est Req
PPP Challenge(Token)
PPP Resp (UID,#PW#)
PPP Link Est Req
PPP Challenge(Token)
PPP Response
(UID,#PW#, IA=SIDBAP)
RADIUS Auth Req
(UID,Token,#PW#,IA=SIDBAP)
Auth Accept
(L2TP Tunnel End Pt, Tunnel Id)
L2TP Tunnel Est Req
(Tunnel Id,UID,Token,#PW#)
PPP Link Est Resp
L2TP Tunnel Est Resp
PPP Link Est Resp
RADIUS Auth Req
(UID,Token,#PW#,IA=SIDBAP)
Auth Accept
PPP IPCP Config Req (IP Adrs)
PPP IPCP Config Resp
RADIUS Accounting Req
(IP Adrs,SIDBAP)
RADIUS Accounting Resp
RADIUS Accounting Req
(IP Adrs,SIDBAP)
NB This example shows the case of an Intermediate
Agent at the DSLAM signalling the SIDBAP and the
ISP’s LNS allocating IP Addresses.
Figure E2: Network Attachment for PPP Tunnelled via L2TP to ISP
RADIUS Accounting Resp
LIS
BB
Customer
OSSLLP
OSSBAP
OSSISP
LIS
Provision
BB Service Req (Billing Adrs, Inst Adrs)
BB Service Req (RefISP,MPF,Inst Adrs)
BB Service Req (RefBAP, MPF, Inst Adrs)
BB Service Resp (RefBAP,SIDLLP)
BB Service Resp (RefISP,SIDBAP)
LIS Add Info (SIDBAP, Inst Adrs)
Audit
BB Inst Adrs Audit Req
(List[SIDLLP])
BB Inst Adrs Audit Req
(List[SIDBAP])
BB Inst Adrs Audit Resp
(List[SIDLLP,Inst Adrs])
BB Inst Adrs Audit Resp
(List[SIDLLP,Inst Adrs])
LIS Add/Remove/Modify Info
(SIDBAP, Inst Adrs)
Figure E5: BB Provision and Audit on a MPF Line For Binding of Service Identifier (SID) to Installation Address (Inst Adrs)
Basic UK LIS interfaces
Interface (c)
LIS
HELD Server
iM1
iB1
LIS
OSS/
CRM
Systems
IP@ translation;
Border Functions
NAPT/SBC/ALG
iC1
iL2
Network
Other LIS
elements
Implications
Yes, automated routing and location provision is technically
feasible (for DSL case) but will imply :• 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
• Detailed document is now in final stage of NICC review process
…………………..
Challenges to adoption
• ISPs storing and updating association of
IP/Line ID/ location at an ISP LIS
• LIS cascades to access providers and
length of response times
• Challenging business cases (!) unless
regulatory driven
• Current regulatory responsibility unclear
when several CPs and an ISP involved
Next Steps
- Continued work on other UK scenarios
(Wireless, Private networks)
- International Scenarios : national solns
need to evolve to cover international IP
roamers
- Long transition periods with hybrid TDM/IP
services
- IP end-to-end (as NGN, PSAP +device
capabilities become clear)  i3 / IETF Ecrit
Back-ups
xDSL Architecture for PPP BRAS Terminated Access
User
Environment
Local Loop
Provider
OSSLLP
Backhaul &
Aggregation
Provider
iM1
OSSBAP
Management
Internet Service
Provider
iM2
Emergency
Handling
Centre
OSSISP
iM3
Control
iM4
BAP
RADIUS
Server
VPC
LIS
iBB5
(RADIUS)
ISP
RADIUS
Server
iBB3
(RADIUS)
iBB2
(PPPoE)
BRAS
DSLAM
Residential
G/W
Voice
Terminal
Media
iBB1
(PPPoATM)
iBB4
(RADIUS)
SIP
IP N/W
RTP/RTCP
Internet
Telephony
Service
Provider
Network Attachment for PPP Terminated Access
iBB2
(PPPoE)
BRAS
DSLAM
Residential
G/W
iBB1
(PPPoATM)
iBB3
(RADIUS)
BAP
RADIUS
Server
iBB4
(RADIUS)
ISP
RADIUS
Server
iBB5
(RADIUS)
PPP Challenge(Token)
PPP Challenge(Token)
PPP Resp (UID,#PW#)
PPP Response
(UID,#PW#, IA=SIDBAP)
Access Req
(UID,Token,#PW#,IA=SIDBAP)
Access Acpt
(BRAS Info)
Acc Req
(UID,Token,#PW#,IA=SIDBAP)
PPP Success
PPP Success
Acc Acpt
(IP Adrs)
Accouting Req
(IP Adrs,SIDBAP)
Accouting Resp
LIS
NICC Standard – end to end
CLI
EACR/PSAP
EISEC
ISP OSS
Installation Adrs
Line ID -> Installation Adrs
Location
Info Svr
CLI
Installation Adrs
CLI+ITSP
IP Adrs
Installation Adrs
VPC
Emergency
Handling
Installation Adrs Centre
CLI, ITSP
CLI, ITSP -> IP Adrs
PSTN
IP Adrs-> Line Id
TDM
Gateway
ITSP
Call Svr
Home
Hub
BB Platform
Public
Internet
IP
Gateway
IPeXchange