IMS based PSTN/ISDN Emulation Achievements & Experiences Dan CHEN, Ph.D. IMS chief engineer Email: chen.dan@zte.com.cn
Why IMS based PSTN/ISDN emulation? What is IMS based PSTN/ISDN emulation?
Why IMS based PSTN/ISDN Emulation A. Power Consumption - 34%* B. O&M - 53%* C. Maintenance Resources -66%* D. Footprint -37%* Avoid high maintenance fee of legacy switches Save the cost of first adopting Softswitch and migrating to IMS later Introduce centralized core as the unique control and service triggering platform for both fixed and mobile networks Add new value-added services for legacy users, such as one number and converged Centrex * Source: one of ZTE IMS based PSTN Emulation Projects
Architecture of IMS-based PSTN/ISDN Emulation Service Layer BOSS MMTEL AS (PSS/PES) AS IN Core Layer EMS IM-SSF I/S-CSCF Other Network PSTN TS ISUP IM-MGW V5/V5ISDN ONUONU MGCF H.248/M3UA V5UA/IUA TG PRI H.248 AG POTS P-CSCF H.248 NCS/H.323/MGC P Terminal Access Layer H.248/ LAN/xDSL/ xpon LS LS PBX IP PBX All users (broadband access and narrow band access) are controlled by an unified IMS core network. MMTEL AS serves for both 3GPP users and H.248/ISDN(BRI/ PRI),V5,H.323, NCS, MGCP, normal users.
PSTN Class 5 Emulation Solution MMTEL AS I/S-CSCF PSTN LS LS P-CSCF H.248 LS LS H.248 V5UA/IUA H.248 PRI/V5/ISDN H.248/ ONU ONU LAN/xDSL/ xpon ONU Swap aged PSTN Switches with, which connects with IMS core via /P-CSCF. PRI/V5/ISDN users remain unchanged and access IMS via /.
Two Approaches for PSTN/ISDN Emulation + IMS Core MMTEL AS is the service control point for all the AG users I/S-CSCF could support multiple types interfaces beyond standards + P-CSCF VGW ( AG) P-CSCF IP Network H.248/IUA/V5UA/H323 H248 AG Each AG is the service control point for its users AG only supports ISDN POTS PBX POTS ISDN phone PBX
Business Trunking Solution Trunk Model PBX connected to MGCF via IM-MGW by trunk to interwork with IMS MMTEL AS I/S-CSCF Subscriber Line model PBX connected to through TG/SG/AG if the uplink interface is PRI PBX connected to /P-CSCF via AG/IAD if the uplink interface is TRK PBX connected to IMS through P- MGCF P-CSCF H.248 IM-MGW TG/SG PRI/ISUP PRI AG/IAD GW TRK IP PBX PRI TDM PBX TDM PBX TDM PBX PBX CSCF through GW
Experiences & Case Studies
China Telecom( Fujian) Solution Highlights NGN SHLR SS TG/SG IMS Core MGCF P-CSCF Province Center Fuzhou Advanced ETCA platform for all elements evolved :CSCF,PSS,, Seamlessly cutover to maintain substantial service experience of PSTN user. Multi domain features Customization ability and fast response help operator keep higher competition in the market AG/EPON AG/EPON PSTN Background AG LAN/xDSL/ xpon Swapping Fujitsu FETEX 150 switch in Aug, 2010 ONUONU ONUONU Establishing an unified core network for both narrow-band and broadband user.
Multi Domain Features in China Telecom Fu Zhou Partial resource managed by Operator B in City B Partial resource managed by Operator A in City A CG MMTEL AS EMS MGCF CSCF Fu Zhou Ning De Nan Ping BOSS BOSS BOSS MGW MGW MGW AG AG AG CS CS CS
Legacy IN Services Experiences ivpn ivpn platform IM-SSF S-CSCF CDM A MSCe MGCF PNP:1002 DN:189xxxxxxxx IMS PNP:1001 DN:5287001 On-net call: one IMS user calls a CDMA user
ISDN/PSTN User Profile Migration Tool Exported Files fr om PSTN CSCF MMTEL AS User Data MGCF MGW
Flexible Provisioning Solution BSS Service Provisioning Node MMTEL AS ENUM/DNS
Highlights of IMS-based PSTN Emulation Realize unified OMM, User DB, service handling & charging to simplify operation & maintenance Break multi-network coexistence with uniform session control & service trigger Unified platform with easy function switch and consolidation Reuse existing equipment to the maximum Lower TCO Convergent network New Services Leverage legacy services Quick and flexible multimedia service delivery capability Adding new value-added services for legacy users, such as one number, converged Centrex, etc Saving the cost & complexity of first adopting Softswitch and then migrating to IMS later Realize convergence of fixed and mobile, broadband and narrowband, provide fullservice operation and enhance operators competitiveness Seamless & Smooth migration High density with multiple access mode capability Backward compatibility with non-ims terminal/device in PSTN