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“Tutorial on Technical Challenges Associated with the Evolution to VoIP”

“Tutorial on Technical Challenges Associated with the Evolution to VoIP”. Presented by: Susan Spradley – President, Wireline Networks Alan Stoddard – General Manager, Carrier Next Generation Networks FCC Office of Engineering and Technology September 22, 2003. Agenda. Introduction

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“Tutorial on Technical Challenges Associated with the Evolution to VoIP”

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  1. “Tutorial on Technical Challenges Associated with the Evolution to VoIP” Presented by: Susan Spradley – President, Wireline Networks Alan Stoddard – General Manager, Carrier Next Generation Networks FCC Office of Engineering and Technology September 22, 2003

  2. Agenda Introduction IP Telephony Overview Technical Considerations Technical Transition Models Business Transition Models Conclusions

  3. Public Internet CMTS Video Feed MTA What is Voice over Internet Protocol (VoIP)? Voice over the Internet (VOI or VON) Public Internet QoS = Best Effort Data Cable Voice over IP “Managed” IP Network QoS = Controlled Load or Guaranteed Wireline Wireless

  4. BETTY JONES 1:05 919-992-1295 Voice Data Video Telecommunication Network Transitions Digital to Packet Multimedia, Personalization Network Consolidation • Evolving Regulations • Multiple Forums Driving Standards Analog to Digital SS7, CLASS features Office Consolidation Clear Regulation/Standards Analog POTS Large Offices One Chief Service Drivers Operation Drivers Regulation & Standards Packet conversion, like Digital conversion, driven by Business Case

  5. Video Data Voice VisionConverged Packet Network • Eliminating Boundaries • Geographic independence • Service flexibility • Service provider reach • Data-voice network consolidation • Central office consolidation • New service opportunities • Desktop Video • Application sharing IP Network Revenue generating and Cost Saving Opportunities

  6. Agenda Introduction IP Telephony Overview Technical Considerations Technical Transition Models Business Transition Models Conclusions

  7. Digital Switching VoIP begins with Digital Voice A D A/D Converter In Digital Switching … … Voice is Data.

  8. Digital Circuit Switching LDSwiches Time Division Multiplexing SingleByte TandemOffice CH0 CH1 CH2 … Channels Channels are ReservedNo Voice and Data IntegrationHierarchical Design EndOffice EndOffice EngineeredBandwidth Remote Remote WastedBandwidth Capacity Maintenance Engineering Used Bandwidth Time High Network Value but … High Network Cost

  9. Engineering Maintenance EndOffice Remote Packet Switching No Tandem LayerNo Remote Layer • Costs • Maintenance Less Equipment Dynamic Bandwidth Allocation • Engineering • Utilization Flat Network MaximumBandwidth Unified Data and Voice • Value • Utilization Unused DataBandwidth Capacity Voice Bandwidth Time Voice and Data Coexist

  10. Value Dynamic Bandwidth Allocation TDM Packet Link Unused Trunk Group 1 Data Trunk Group 2 Voice Trunk Group 3 • Paths Channelized and Grouped • Routes Require pre-Engineered • Unused Channels are Wasted • No prioritization • All Bandwidth is available • Routes Dynamically Switched • Voice is prioritized • Data fills unused space Voice alone gains over 30% higher utilization Data and Voice Coexist Efficiently

  11. EndOffice EndOffice EndOffice EndOffice ATM Cell Switching vs. IP Routing Synchronous Stream Asynchronous Stream Header Payload Header Payload Cell 1 Cell 2 … Cell 0 Fixed Size Multi-Byte Cells Variable Length Multi-Byte Packet ATM Core IP Core Multi-Byte CellsDynamically Allocated Bandwidth Reserved Switched per Session Advanced QOS Variable-Byte Packets No Native Allocation SchemeNo Native Reservation Scheme Packets are Routed Independently Limited QOS Routers are Unaware of Session

  12. Layer 3 Layer 3 Network Network 4 Bits 4 Bits 8 Bits 8 Bits 4 Bits 4 Bits Interface Interface DiffServ DiffServ First 16 Bits of First 16 Bits of DSCP DSCP IP IP Version Version Header Header Field Field IP Data Gram IP Data Gram Length Length Layer 2 Layer 2 ( ( ToS ToS ) ) Data Link Data Link Ethernet Frame Ethernet Frame ETHERNET ETHERNET 802.1 Q/p 802.1 Q/p ATM, etc. ATM, etc. 802.1 Q Tag 802.1 Q Tag 802.1 Q Tag 802.1 Q Tag Source Source Des Des Protocol Protocol Payload Payload Mac Mac Priority Bits Priority Bits Mac t Mac • • • • Priority Bits Priority Bits Layer 1 Layer 1 Type Type VLAN ID VLAN ID • • • • VLAN ID VLAN ID Physical Physical Bandwidth Bandwidth 512 - 12000 CAT 5, Fiber CAT 5, Fiber 48 Bits 48 Bits 32 Bits 32 Bits 16 Bits 16 Bits 48 Bits 48 Bits Bits Smart IP Routers and Switches • QoS management at different layers • Layer 3 - DiffServ Prioritizes Packet Routing • Layer 2 - 802.1 Q/p Prioritizes Ports and Ethernet Frame- Fragment large packets on Low Speed Links • Layer 1 - Overprovision Bandwidth

  13. Speech Codecs G.711: “uncompressed” TDM coding: PSTN standard Compression (reduction in required bit-rate, e.g., G.729) • Accommodate access link speed (e.g., wireless) • Reduce bandwidth needed in core: • trade off compression against cost Concerns • Baseline voice quality will be lower for lower bit-rates • Increased end-to-end delay • Reduced performance with expected packet loss rates • Transcoding • are there other compression codecs in the network? • how often will multiple transcodings occur in a complicated path? • frequency of use for features requiring transcoding conferencing, voice mail

  14. Agenda Introduction IP Telephony Overview Technical Considerations Technical Transition Models Business Transition Models Conclusions

  15. The Voice Quality Problem:How can you know the voice quality is what you want? Application layer Network operator wants: A voice quality indicator Network Engineering Planning Process Network layer Manufacturers specify: Delay, link utilization, buffer size codecs available packet loss rate Need to establish correspondence between the packet level behavior and the quality perceived at the application level.

  16. Engineering VoIP Network Topology Creator (access type, equipment, core) Traffic Profile (loading, %voice/ %data) Controllable parameters (voice codec, packet size, packet loss) Transport & handoff (IP,ATM, TDM, packet islands, TDM handoff) Adjustments to Network Design Analysis of Packet Network Impairments Predicted Network Performance Implementation Operational Measurements(Delay, Packet Loss, Jitter) Results Analysis & Processing

  17. ReliabilityMaintaining service during network failure events • Design & Testing: Reliability Before Deployment • Reliability Analysis: H/W+S/W Failure rate prediction • System and network failure mode analysis • Zero Downtime Upgrade and Maintenance by Design • People & Processes: Responsiveness & Global Support • Traffic assurance verification in Large Office test labs • Large System Integration Centers in all market environments Asia, NA, SA, Europe, Asia • Architecture: Engineered for Redundancy & Survivability • Self-Healing, Recovers in a Crisis • Overload Controls incl. Priority Service to Essential Services • Lawful Intercept (CALEA) • "I find that the harder I work, the more luck I seem to have." • - Thomas Jefferson

  18. Maintaining Security with VoIP Voice Network Traffic VoIP Shared Channels TDM Dedicated Channels Control (OAM&P) Remove Security Hurdles: • Strong device authentication • Secure OAM / Encryption • Strong operator authentication • Network partitioning & access control • Voice and signaling accessibility Signaling Bearer/Data Public Network Public Network Network Security Hurdles: • Theft of Service • Service Disruption • Privacy • Bearer - eavesdropping • Signaling – collect caller ID / information • Control - theft of subscriber info

  19. Key Packet Bearer Path Signaling Path TDM Bearer Path TDM Office TDM Office Packet Interconnect Between Carriers Network 2 Network 1 ISUP Call Server Call Server Remove Barriers to Cost Reduction with Standardization of: • Signaling Protocols • Media Protocols • Services Delivery • Packet Interconnect Rules & Billing Agreements Allow Carriers to Maximize Voice over Packet Architecture Advantages (1) Tandem (2) Local or Tandem Offnet Traffic Between Networks - Significant & Growing Percent of Total Minutes Packet Network C A B D GW GW GW GW

  20. Agenda Introduction IP Telephony Overview Technical Considerations Technical Transition Models Business Transition Models Conclusions

  21. Technical Transition Models • Transition Models • Enterprise Networks • IP PBX • Hosted Services • VoIP VPNs • LD Networks • Local Networks • Beyond Voice -- Multimedia Networks

  22. Transition Models Evolve - Add IP interfaces to existing TDM infrastructure, new growth on VoIP Rip & Replace - Replace existing TDM infrastructure with VoIP Overlay - Grow all new line and trunks on VoIP, Cap TDM Total Cost - $$ Total Cost - $ Total Cost - $$$ Softswitch Hybrid Softswitch Softswitch TDM Carrier + Carrier Hosted VoIP Carrier Hosted VoIP Enterprise Hybrid IP PBX PBX or Key System or + IP PBX IP PBX

  23. Enterprise Transition IP PBX Remove Barriers to Profitability • Retail IP Phones provide cost and feature flexibility • Reduced cost IP connectivity to PSTN • Enhanced end user mobility (campus-wide) – increased productivity • Evolve - Hybrid IP PBX • Churn users as needed – growth or service mobility • Leverage existing CPE • Ovrelay (New) / Replace - IP PBX • New offices or branch sites • Minimize in-building wiring by using data only connection Over 25% of the US PBX base expected to be IP-enabled by year end 2005

  24. LD Provider Local Provider HQ Site 1 IP PBX Sites IP PBX Sites PBX Sites Data Provider HQ Site 2 IP Centrex Sites Key System Sites IP Centrex Sites Key System Sites Centrex Sites Centrex Sites Enterprise Transition Separate Interconnect to VoIP VPN VoIP VPN Provider HQ Site 1 HQ Site 2 PBX Sites • Separate voice & data links • Separate local PSTN & LD connectivity • Complex mgmt, inefficient b/w use • Converged links – local, LD, data • Simple mgmt, efficient b/w use • Improved access for remote users Remove Barriers to Outsourced Private Networking Drive New Carrier Revenue / Customer Retention

  25. Enterprise Transition Hosted VoIP (IP Centrex) Remove Barriers to Outsourced Voice – Save up to 35% over IP PBX • Retail IP Phones provide cost and feature flexibility • Outsource but retain control with improved end user management tools and simplified moves, add, changes • Avoid Long Distance charges • Enhanced user mobility and feature transparency – campus-wide, at home, remote offices, on the road – for improved productivity Drive High Margin Carrier Revenue Stream - Differentiated Service Bundle • Evolve – Hybrid IP Centrex • Churn users as needed – growth or service mobility • Leverage existing CPE • Overlay (New) / Replace - IP Centrex • New offices or branch sites • Minimize in-building wiring by using data only connection

  26. Long Distance Transition Remove Barriers to Carrier Expansion & Service Introduction • Improved Capacity - Relieves CPU Exhaust • Fewer Trunk Groups, Muxes, X-Connects & Simplified Trunk Rearrangement • 15-25% Reduction of Interconnect Ports between Switches • Ability to Address New Markets at Low Cost Provide up to 20% Carrier Cash Flow Improvement and Packet Infrastructure to Speed IP Services Delivery VoIP VoIP • Overlay • Add additional switching nodes • Groom trunks to new VoIP nodes • Interconnect inefficiencies between TDM and VoIP • Evolve / Replace • Convert or replace existing nodes • Delay additional switching nodes for later growth • Limit operational expense

  27. VoIP Local Network Transition Remove Barriers to Carrier Expansion & Service Introduction • Eliminate Tandems, X-Connects, Trunking between Switch Nodes • Reduce Switch Nodes by 50-85%, Equipment by 60-80%, B/W use up to 30% • Expand Out of Territory at Low Cost • Retain / Grow Centrex - National Centrex, Centrex IP, Churn PBX to Hosted IP Provide 10-20% Carrier Cash Flow Improvement and Packet Infrastructure to Speed IP Services Delivery VoIP • Overlay • Add additional switching nodes • Groom trunks to new VoIP nodes • Interconnect inefficiencies between TDM and VoIP • Evolve / Replace • Convert or replace existing nodes • Delay additional switching nodes for later growth • Limit operational expense

  28. Beyond Voice – Multimedia Transition Multimedia Existing Phone Overlay (New) / Replace • IP phone required • Softclient flexibility – PDAs and PCs become phones • Voice becomes a subset of data services bundle – delivered over DSL or data connection Evolve - Converged Desktop • Traditional voice services maintained with new multimedia add-ons • Existing desktop retained - new phone upgrades at end user driven pace • Utilizes existing TDM SIMRING or IN • Enables ubiquitous service delivery Remove Barriers to New Service Introduction • Simplify communications – Personal Communications Mgr, Unified Messaging • Enhance productivity – Video Calling & Conferencing, Web-Push / Co-Browsing Provide New Carrier Revenue Stream & Differentiate Service Set

  29. Agenda Introduction IP Telephony Overview Technical Considerations Technical Transition Models Business Transition Models Conclusions

  30. Business TransitionNetwork separate from Service • Network Transition • Competitive Local: Cable, W-, CLEC • Cities/Municipalities? • More Competitive LD: IXC vs LEC • Data Access: • Res: DSL vs Cable • Biz: LEC vs IXC • Emerging Acccess Implications? • Wireless LANs • Fiber to the Home (FTTH) • Services Transition • Voice: LECs  to Cable, W-, CLEC • Video: Cable  Broadband • IM: Yahoo, AOL  to ASP • Client Based Services • SIP Clients • Peer to Peer • Napster Model • Service Provider Based Service • Yahoo, AOL, Microsoft, Apple • Business specific Companies • Bring your own broadband Separating Service & Network permits Service ubiquity independent of access

  31. Business TransitionTransition Squabble, Struggle, Brouhaha Cable Co’s Yahoo/AOL/MSN LECs • Services • IM: Yahoo, AOL  to ASP • Voice: LECs  to Cable, W-, CLEC • Video: Cable  Broadband • Next Gen: Yahoo, AOL, Microsoft, LECs, IXCs, etc. • Network/Access • Competitive Carriers: Cable, ISPs • International Carriers: AT&T • Data Carriers: UUNET • Res: DSL vs Cable • Biz: LEC vs IXC • Implication of Wireless LANs, Hot spots Apple/Microsoft Wireless Carriers Industry Specific (e.g. Banks, Gaming, Brokerage..) Cities/ Municipalities CLECs IXCs Market will determine Niche vs End-to-End providers

  32. Business TransitionNew Models Providers move with customer to new Business Models • Network Based Services • Network operators provide Service based on Access (Network + Services) • Partnerships: Yahoo/SBC - MSN/Verizon • Mergers? • Can drive Uniformity/Ubiquity • Service Provider Based Services • ISPs offer ad hoc, interpersonal communications brokerage • Bring your own broadband • Fwd.pulver.com, IM, Email • Reliability required? Wiretap required? • Client Based Services • Peer-to-Peer • Web/Napster • Pre-arranged Address exchange • SIP based clients Regulation will impact viability of new Business Models

  33. Agenda Introduction IP Telephony Overview Technical Considerations Technical Transition Models Business Transition Models Conclusions

  34. Conclusions • Technology is decoupling Service from Access • Users desire ubiquitous service access, personalization and the freedom of mobility • There are technology challenges that need to be considered in developing and deploying IP Telephony • There are both technical transition and business transition models to consider

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