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인터넷 CTI 기술 ’99. 2. 김원순 로커스 정보통신연구소 HSN’99 by wskim -1- CTI LEADER Internet CTI • CTI Evolution • Voice over Packet Network – H.323 Protocol • Case Study – VoIP : Excel Strategy HSN’99 by wskim -2- CTI LEADER CTI Evolution CTI Is Ready For Prime Time Deployment TSAPI, TAPI CallPath Server CTI Servers Rockwell Transaction Link 1982 HSN’99 by wskim IVR IBM CallPath DEC CIT HP ACT 1990 1986 -3- ECTF S.x00 ECMA CSTA VoIP H.323 1994 CTI LEADER CTI in the 90’s . . . Factors Favoring CTI Business Competition Customer Care Consolidation Reengineering Technology IEC Services CPE Features Life Cycle Price Pressures HSN’99 by wskim -4- CTI LEADER Generic CTI Capabilities • “Screen Pop” ANI DNIS IVRU Inbound/Outbound Increased Productivity • Skills Based Routing • Voice and Data Transfer Improved Customer Service Person-to-Person IVRU-to-Person • Information Who Called What Happened HSN’99 by wskim -5- CTI LEADER CSR Contact Management SW Business Application RDBMS CTI Application ACD HSN’99 by wskim CTI APIs -6- Legacy System Connectivity Management (TP Monitor) Call Center Server Components Legacy Systems CTI LEADER CTI Evolution Written Procedures Electronic Mail Groupware & Workflow Computing Internets Intranets Vendor- Open MM Specific CTI InteCTI Standards gration Real-time Value Creation 7 Business Processes & Organization Online EDI Order Forms Web-enabled Call Centers Users, Clients & Suppliers Telecommunications Voice Mail ACD/IVR Call Centers Phone HSN’99 by wskim -7- Source: Gartner Group CTI LEADER Customer Contact System Network Call Center N Call Center 2 Information Technologies Call& Voice Processing Fax/EDI/Image Dialer IVR Public Telephone Network MIS ACD Callers Internet Legacy Systems FMS TCP/IP Information Tools Open Apps. CTI Server CMS Network Based Enhanced Features Desktop HSN’99 by wskim -8- CTI LEADER CTI Functionality Mapping Difficult Easy Financial Value $ High Screen Pop Database Routing $ Low Skills Routing Softphone Measurements Blending Implementation Difficulty HSN’99 by wskim -9- CTI LEADER CTI Technology Support Representatives to Provide Integrated “One and Done” Service Old System New System Accounts Empowered Customer Service Agent Contact Customer “Not my problem.” Information Quotes Information Needs Customer “Yes, I can do it.” Marketing Works Appoints Contact Management Debt Recovery Billing • Separate information systems by functionality. • Seamless interface between information systems. • Specialized agents by function. • All agents able to access all information. • Systems designed for ease of call center use. • Systems often require expert knowledge. • Agents enabled to make on-the-spot decisions. • Complex decision-making hierarchy. • Effective “corporate memory.” • Service not linked from call to call. HSN’99 by wskim - 10 - CTI LEADER CTI Applications Messaging Vociemail LAN Fax E-mail Database Access IVR Fax-on-Demand ADSI Connectivity Co Carrier AIN-IP Service Node Voice/Data Integration HSN’99 by wskim - 11 - Audio-Conferencing Automated Dialing Integrated Call Center CTI LEADER Technology Tree È£Á¦¾î ÀÀ¿ë ÀÀ¿ë¼-ºñ½º ·¹º§ Åë½ÅÅëÇÕÁ¦¾î ·¹º§ ¹Ìµé¿þ¾î ·¹º§ ¸ÅüÁ¦¾î ÀÀ¿ë µ¥ÀÌŸº£À̽º Á¦¾î ÀÀ¿ë ÄÄÇ»ÅÍ Åë½ÅÅëÇÕ Á¦¾î (¼¼¼Ç,±×·ì,¿¬°á,Æ÷Àå) Inbound Signal Outbo -und Signal PCM À½¼º ¾ÐÃà À½¼º ¾ÐÃà Fax µ¥ÀÌÅÍ À½¼º ÀÎ½Ä µ¥ÀÌÅÍ º£À̽º º¸¾È Transport Network Infrastructure °øÁß±³È¯ ³×Æ®¿öÅ©±¸¼º À½¼º¸Á ·¹º§ °øÁß±³È¯ À½¼º¸Á HSN’99 by wskim °øÁß±³È¯ ½ÅÈ£¸Á ATM ¼¿·ê ·¯/ PCS - 12 - ¹«¼±È£Ãâ À§¼º LAN/ Interne t CTI LEADER “the killer app of the Internet” 1993: “the network is the computer” 1993 response: “Huh?” 1996: “the network is the computer” 1996 response: “Obviously...” 1996: “...customer interaction will be the killer app of the Internet...” -- Dr. Eric Schmidt, Chief Technology Officer, Sun Microsystems 1996 response: “Hmm… ” 1999 response: “ ” HSN’99 by wskim - 13 - CTI LEADER Three Stages of Customer Interaction Channel Integration Established Channels will be increasingly augmented by Internet and Web-related technologies. Each of the technologies outlined below are available today. Several still require improvements in scalability, security, or robustness; but, none are fantasy... ESTABLISHED CHANNELS Direct Physical Interaction Direct Mail Telephone Person-to-Person VRU Fax HSN’99 by wskim SUDDENLY REQUIRED CHANNELS Web-based information display Web-based forms Callback Request Email Web-based “VRU” - 14 - EMERGING, EXCITING CHANNELS Web-based chat Internet telephony Hybrid telephony Application/page sharing Videoconferencing CTI LEADER Voice over Packet Network • Architecture – – – – Delivering QOS Voice over WAN Voice QOS point of measure Voice over Broadband- Vision • H.323 Protocol HSN’99 by wskim - 15 - CTI LEADER Delivering QOS Signaling Control of Latency Bandwidth Reservation Type of Voice vs data vs fax Minimum Delay Variation QOS based Routing Path selection dependent on QOS, fixed during the call Multiple priority levels, avoiding tandem points Constrained delay variation even under congestion Minimum bandwidth allocation for the call with connection admission controls HSN’99 by wskim - 16 - CTI LEADER Voice over WAN Circuit Switched Vo ice Network Voice over IP Voice over FR Voice over FR VOice over AT M VOice over AT M HSN’99 by wskim . Voice over IP . QOS via RSVP . Multiple priority queueing . Voice over frame relay . SVCs . QOS via FR traffic classes . Local fragmentation at UNI . Voice over ATM .Variable bitrate (VBR-RT) . SVCs - 17 - CTI LEADER Where Are We on Voice QOS? Signaling IP FR ATM Control of Latency Bandwidth Reservation RSVP bandwidth reservation effectiveness yet to be proven QOS based Routing ? Minimum Delay Variation ? ? RSVP bandwidth reservation effectiveness yet to be proven ATM designed for mixed non-real-time & real-time services HSN’99 by wskim - 18 - CTI LEADER Voice Networking over Broadband : The Vision Circuit Switched Voice Network Voice FRAD Wireless V/IP LAN Data network Native ATM . Voice : an element of multimedia applications . Voice over IP . QOS-sensitive LANs . RSVP mapping to ATM COS . Seamless voice networking featuresI . Voice over frame relay . Interoperability with ATM . VOice over ATM . Voice VPN equivalency Voice Everywherel Multimedia Call as Simple as Voice Call HSN’99 by wskim - 19 - CTI LEADER VoFR, VoATM, VoIP Opportunity Unacceptable Utility Quality Business Quality Toll Quality Cellular Cost ($) Internet PSTN Voice Vo ATM Vo ATM (8 Kbps) (PCM/AAL1) Intranet Vo FR Vo IP HSN’99 by wskim - 20 Quality CTI LEADER H.323 Protocol • Components – Terminal – Gatekeeper, Gateway • Protocol Flows – – – – Call Establishment Control Signaling Flows Media Stream and Media Control Flows Call Release HSN’99 by wskim - 21 - CTI LEADER H.323 Protocol H.323 IP-based visual telephone systems & terminal equipment—covers video conferencing audio, video, graphics, encryption, multipoint Compression algorithms from 64 Kb/s to 2.048 Mb/s CIF/QCIF H.323 Compression algorithms twice as efficient as H.261 H.261 H.263 H.245 control and indication for frame sync Audio standards G.728 H.245 G.711 3kHz audio into 56/64Kb/s streams G.722 G.711 G.722 7kHz wideband 48/56/64 Kb/s stream hi-fidelity audio G.723 G.729 H.245 HSN’99 by wskim H.225 frame structure T.120 Point-to-point and multipoint data conferences (not truly part of the H.32X standard) High H.323 Res JPEG graphics JPEG still video standards Custom or non-standard graphics not prohibited by H.320—systems must be the same G.723 6.3 Kb/s stream G.729 8.0 Kb/s stream H.225 H.245 establishing communications Control Multipoint control units control - 22 - CTI LEADER Terminal Audio Apps Video Apps G.711 G.729 G.723. 1 H.261 H.263 Terminal Call Manager RTCP H.225.0 RAS H.225.0 H.245 Call Control Signallin Signallin g g T.120 Data RTP Transport Protocols & Network Interface HSN’99 by wskim - 23 - CTI LEADER Gatekeeper Gatekeeper Manager Billing Services H.225.0 RAS (server) H.225.0 Call Sig. H.245 Control Sig. Directory Services Security Services Transport Protocols and Network Interface HSN’99 by wskim - 24 - Policy-based Call Management Services CTI LEADER Gateway Billing Services Interworking Call Control Gateway Call Manager RTP RTCP H.225.0 RAS (client) H.225.0 Call Signallin g Transport Protocols & Network Interface HSN’99 by wskim - 25 - SCN Signalling Call Control Layer e.g. Q.931 H.245 Control Signallin g SCN Signalling Link Control Layer e.g. LAPD SCN Signalling Physical Interface CTI LEADER Call Establishment Flows ARQ(1) ACF(2) SETUP(3) CALL PROCEEDING(4) ARQ(5) ACF(6) ALERTING(7) CONNECT(8) H.225 Signalling Message RAS Message HSN’99 by wskim - 26 - CTI LEADER Control Signaling Flows TerminalCapabilitySet(9) (10) TerminalCapabilitySetAck ) TerminalCapabilitySet(11 TerminalCapabilitySetAck (12) OpenLogicalChannel(13) OpenLigicalChannelAck(14 ) OpenLogicalChannel(15) OpenLogicalChannelAck(16 ) H.245 Message HSN’99 by wskim - 27 - CTI LEADER Media Stream and Media Control Flows RTP Media Stream(17) RTP Media Stream(18) RTCP Messages(19) RTCP Messages(20) RTP Media Stream and RTCP Message HSN’99 by wskim - 28 - CTI LEADER Call Release End Session Command(21) End Session Command(22) RELEASE COMPLETE(23) DRQ(24) DRQ(24) DRQ(24) DRQ(24) H.225 Signalling Message RAS Message H.245 Message HSN’99 by wskim - 29 - CTI LEADER PSTN to IP to PSTN call Flow Voice Lines/Trunks MF, ISDN, R2, etc. Voice Lines/Trunks MF, ISDN, R2, etc. Internet Protocol Networks Internet Telephony Switch PSTN Telephone Switch 2 8 6 H.323 Gateway 3 1 Gatekeeper Internet Telephony Switch H.323 Gateway 7 LAN/WAN Gatekeeper 4 5 H.323 Terminals HSN’99 by wskim - 30 - CTI LEADER PSTN Telephone Switch H.323 Terminal to PSTN call Flow Internet Telephony Switch PSTN Telephone Switch Internet Telephony Switch H.323 Gateway H.323 Gateway 5 LAN/WAN 4 2 Gatekeeper 6 1 Gatekeeper 3 H.323 Terminals HSN’99 by wskim - 31 - CTI LEADER PSTN Telephone Switch PSTN to H.323 Terminal call Flow Internet Telephony Switch PSTN Telephone Switch H.323 Gateway Internet Telephony Switch H.323 Gateway 3 LAN/WAN 2 4 1 Gatekeeper Gatekeeper 6 5 H.323 Terminals HSN’99 by wskim - 32 - CTI LEADER PSTN Telephone Switch Standard Status • H.323 단점 – 프로토콜 불완전성으로 상호운용성 저하 – WAN에 맞지 않은 긴 설정지연 : 8-30 sec – 새로운 기능 추가시 프로토콜 복잡 • SIP(Session Initiated Protocol) – 패킷 단위의 빠른 설정 – 새로운 기능의 추가 용이 – 표준화 시작 상태 HSN’99 by wskim - 33 - CTI LEADER Case Study • Programmable Switch • Voice Over IP: Excel Product Strategy HSN’99 by wskim - 34 - CTI LEADER Computer Technology Special Purpose Computing Large, Commercial Applications Open Systems Open, Scalable, Distributed Systems 1950............1960...................1970.................1980......................................................... Switch Technology Special Purpose Switching Large Switching Applications Programmable Open Switches Open, Scalable, Distributed Systems 1960.................1970.................1980..................1990................................. HSN’99 by wskim - 35 - CTI LEADER CO 교환 장비 • 특징 : – 대용량 처리에 적합 – 최고의 시스템 안정성 – 고도의 호처리 용량 및 성능 지원 • 한계점 : – • • 사설교환장비 개방형 교환장비 특징 : • – 소용량의 교환 장비로 설계 – 개방형 API (서비스 개발의 용이) – 가입자 회선 중심의 설 계 – 용량의 확장성 (응용서비스별) – 복수서비스 수용 – 빠른 서비스 개발/수정 – 높은 신뢰성 – 낮은 초기 투자비 및 낮은 운영비 한계점 : – 단순 교환 기능 이외 부 가기능 구현의 한계성 – – 통신 장비의 단계별 점 진적 확장의 어려움 – – 응용서비스 및 신호처 리에 대한 변경 및 추가 의 어려움 (비용, 시간) HSN’99 by wskim 특징 : – – 기간통신 사업자용 설계 구조가 아님 신호처리 기능의 한계성 - SS7, ISDN-PRI 등 불완전한 이중화 및 Hot Swapping 기능 응용서비스 개발의 어려 움 신호처리 프로그램 개발 의 어려움 - 36 - CTI LEADER VoIP Applications • • • • • International Long Distance VoIP-enabled ESPs Unified Messaging Fax over IP Virtual 2nd line HSN’99 by wskim - 37 - CTI LEADER Excel VoIP Product Strategy • VoIP as a Plug-in Technology • Transparent to Excel API • Open Architecture to allow Integration of Multiple VoIP Technologies • H.323 Industry Standard Product to work with other Gateways as well as End-user PCs • Evolution to Converged Voice/Data Backbone for EXS Architecture HSN’99 by wskim CTI LEADER VoIP Product Directions • VoIP via EXNET Connect – Fastest Time to Market – Integrate 3rd Party VoIP Solutions VocalTec , AudioCodes, NMS Fusion, Dialogic – Integrate as Network Interface Layer-3 to EXS Call Control Transparency to Applications • VoIP EXS Chassis Solution – – – – Higher Density, Lower Cost per Port Excel Redundancy Solutions Higher Level of Integration, Voice/Data Backbone Same API HSN’99 by wskim CTI LEADER VoIP with EXNET Connect Host ISA Bus Excel Programmable Network Protocol Development 41 # Page ofp 41.2 af51 () FWD R2 XMIT DIG CTR = -1 onp 41.5 af47 () Reset FWD R2 DIG CTR to 1 (101)NETevL3_INT_EVENT_1 (32) NETevBWD_R2_SIG_2 SI 63 af48 (2) OUTP the next FWD MFC R2 SIG <Stage #> af68 (15) OUTP FWD MFC SIG af52 () FWD R2 XMIT DIG CTR = -2 (37) NETevBWD_R2_SIG_7 af5 (1, 23) Set PPL Timer <Timer #> <Timer ID> af53 () FWD R2 XMIT DIG CTR = -3 onp 41.3 (38) NETevBWD_R2_SIG_8 S 41 onp 41.2 af12 (176) SND INSZ/OUTZ Control Error (46) NETevTIMER1 (31) NETevBWD_R2_SIG_1 (45) NETevBWD_R2_SIG_15 (34) NETevBWD_R2_SIG_4 (35) NETevBWD_R2_SIG_5 af49 () FWD R2 XMIT DIG CTR = +1 ofp 39.3 (33)NETevBWD_R2_SIG_3 ofp 45.0 (100) NETevL3_INT_EVENT_0 SI 42 (101) NETevL3_INT_EVENT_1 Pentium Media CPU Rsrce. Telephony - Std. Bus af48 (2) OUTP the next FWD MFC R2 SIG <Stage #> ofp 43.0 (5) NETevRCV_LINE_SIG_0101 (34) af50 (2) GEN DEC EV Type 11 <Stage #> af5 (1, 22) Set PPL Timer <Timer #> <Timer ID> ofp 39.1 onp 41.1 af12 (177) SND INSZ/OUTZ Control Error af7 () Cancel R2 Reception ofp 50.0 af68 (15) OUTP FWD MFC SIG ofp 41.3 ofp 41.5 EXNET Connect Media Chassis PSTN 02/24/94 Date: onp 41.0 onp 41.4 af54 (2) GEN DEC EV Type 12 <Stage #> NETevL3_INT_EVENT_0 IP Network EXNET VoIP Media Resources 16K Port VOIP Gateway HSN’99 by wskim CTI LEADER EXNET Connect VoIP Benefits • Carrier Class Product – Capacity - 30k ports in EXS today: 15k network ports + 15k VoIP ports in a single system. – Complete System Redundancy available – Hot Swap capability on Gateways • Easy Integration into Existing Systems – Application processes VoIP Calls using existing Excel API – Adding VoIP Gateway analogous to adding new type of line interface like ISDN PRI or SS7 • Fastest Time to Market HSN’99 by wskim CTI LEADER Integrated VoIP - VDAC EX/CPU I/O EX/CPU EX/CPU I/O EX/CPU T1/E1/J1 I/O Ethernet I/O Ethernet I/O T1/E1/J1 Line Cards P a c k e t B u s L N X B U S SS7 Card VDAC VDAC DSP-ONE POWER HSN’99 by wskim • Complete H.323 Gateway on a Card – H.323 Stack Processing • • • • H.245/H.225 PPL Call Control Packetization Echo Cancel, Jitter Buffer Multiple Voice Codecs (G.729A, G.723) – Voice Activity Detector – DTMF Detect/Generation • 32 54x-based DSPs • 128 VoIP ports per card Embedded Host CTI LEADER VDAC Solution Benefits • Reduced System Cost and Footprint • Improved Reliability – Card Level Hot Swap & Full EXS Chassis Redundancy Options • Scalability - Scales to Maximum Size of EXS • Same API for Applications as EXNET Connect VoIP • Open DSP Environment Allows Integration of Multiple VoIP or SIP Stacks – Early adopter of new technologies, higher density technologies – Interoperate between different VoIP vendors, standards • Integrated Management with EXS Manage • Core Technology for IP-based EXNET HSN’99 by wskim CTI LEADER IP Based EXNET Architecture Media Processing PSTN EXNET IP Backbone Media Processing HSN’99 by wskim CTI LEADER VOIP EXNET backbone EX/CPU EX/CPU I/O EX/CPU EXNET Connect Excel Programmable Network Protocol Development 02/24/94 Date: 41 # Page onp 41.0 onp 41.4 af54 (2) GEN DEC EV Type 12 <Stage #> ofp 41.2 af51 () FWD R2 XMIT DIG CTR = -1 onp 41.5 af47 () Reset FWD R2 DIG CTR to 1 (101)NETevL3_INT_EVENT_1 (32) NETevBWD_R2_SIG_2 SI 63 af48 (2) OUTP the next FWD MFC R2 SIG <Stage #> af52 () FWD R2 XMIT DIG CTR = -2 NETevL3_INT_EVENT_0 af68 (15) OUTP FWD MFC SIG (37) NETevBWD_R2_SIG_7 af5 (1, 23) Set PPL Timer <Timer #> <Timer ID> af53 () FWD R2 XMIT DIG CTR = -3 onp 41.3 (38) NETevBWD_R2_SIG_8 S 41 onp 41.2 af12 (176) SND INSZ/OUTZ Control Error (46) NETevTIMER1 (31) NETevBWD_R2_SIG_1 (45) NETevBWD_R2_SIG_15 (34) NETevBWD_R2_SIG_4 (35) NETevBWD_R2_SIG_5 af49 () FWD R2 XMIT DIG CTR = +1 ofp 39.3 (33)NETevBWD_R2_SIG_3 ofp 45.0 af50 (2) GEN DEC EV Type 11 <Stage #> af5 (1, 22) Set PPL Timer <Timer #> <Timer ID> (100) NETevL3_INT_EVENT_0 SI 42 (101) NETevL3_INT_EVENT_1 af48 (2) OUTP the next FWD MFC R2 SIG <Stage #> ofp 43.0 (5) NETevRCV_LINE_SIG_0101 (34) ofp 39.1 onp 41.1 af12 (177) SND INSZ/OUTZ Control Error af7 () Cancel R2 Reception ofp 50.0 af68 (15) OUTP FWD MFC SIG ofp 41.3 PCI Bus ofp 41.5 DSP Voice Bus Host H.323 Gateway EX/CPU I/O EXNET EXNET I/O T1/E1/J 1 I/O Pentium CPU L N X B U S T1/E1 Standby POWER EXNET Controller T1/E1/J1 Line Cards SS7 Controller Redundant T1/E1/J1 NIC EXS Node GateKeeper Circuit Switched Network Packet Network HSN’99 by wskim - 45 - CTI LEADER Ethernet backbone Call Control Host GateKeeper, MCU Ethernet Backbone Media Proc. Node IP EXNET Connect Excel Programmable Network Protocol Development 02/24/94 Date: 41 # Page onp 41.0 onp 41.4 af54 (2) GEN DEC EV Type 12 <Stage #> ofp 41.2 af51 () FWD R2 XMIT DIG CTR = -1 onp 41.5 af47 () Reset FWD R2 DIG CTR to 1 (101)NETevL3_INT_EVENT_1 (32) NETevBWD_R2_SIG_2 SI 63 af48 (2) OUTP the next FWD MFC R2 SIG <Stage #> af68 (15) OUTP FWD MFC SIG (37) NETevBWD_R2_SIG_7 af5 (1, 23) Set PPL Timer <Timer #> <Timer ID> af53 () FWD R2 XMIT DIG CTR = -3 onp 41.3 (38) NETevBWD_R2_SIG_8 S 41 onp 41.2 af12 (176) SND INSZ/OUTZ Control Error (46) NETevTIMER1 (31) NETevBWD_R2_SIG_1 (45) NETevBWD_R2_SIG_15 (34) NETevBWD_R2_SIG_4 (35) NETevBWD_R2_SIG_5 af49 () FWD R2 XMIT DIG CTR = +1 ofp 39.3 (33)NETevBWD_R2_SIG_3 ofp 45.0 af5 (1, 22) Set PPL Timer <Timer #> <Timer ID> (100) NETevL3_INT_EVENT_0 SI 42 (101) NETevL3_INT_EVENT_1 af48 (2) OUTP the next FWD MFC R2 SIG <Stage #> ofp 43.0 (5) NETevRCV_LINE_SIG_0101 (34) af50 (2) GEN DEC EV Type 11 <Stage #> ofp 39.1 onp 41.1 af12 (177) SND INSZ/OUTZ Control Error af7 () Cancel R2 Reception ofp 50.0 af68 (15) OUTP FWD MFC SIG ofp 41.3 PCI Bus ofp 41.5 DSP Voice Bus af52 () FWD R2 XMIT DIG CTR = -2 NETevL3_INT_EVENT_0 Pentium CPU EX/CPU I/O EX/CPU EX/CPU I/O EX/CPU IP EXNET I/O T1/E1/J 1 I/O T1/E1 Standby POWER L N X B U S IP EXNET Controller T1/E1/J1 Line Cards SS7 Controller Redundant T1/E1/J1 EXS Node Circuit Switched Network Packet Network HSN’99 by wskim - 46 - CTI LEADER Distributed/IP Interconnection Application Services IP Integrated IN Applications Subscriber Database IP IP CDR Services IP NIU Element Managemen t IP External IN Applications Switching Services VoIP Gateway Media Application Switching Node IP Layer 5 IP Layer 5 - EXS Support Services Layer 4 IP Layer 4 IP EXS Call Control Media Processing IP Layers 1,2,3 IP Layers 1,2,3 - Transport Protocol IP Layer 5 IP Network HSN’99 by wskim - 47 - Telephony Terminal Devices PSTN CTI LEADER 감사합니다. HSN’99 by wskim - 48 - CTI LEADER