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Data, Voice, and Video Convergence on Higher Education Networks

Data, Voice, and Video Convergence on Higher Education Networks. Jim Jokl jaj@Virginia.EDU August, 2000. The Traditional Campus Network Model. Telephone service Manages PBX or Centrex, cable plant Usually self-funded via chargeback Data network service Typically part of computing center

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Data, Voice, and Video Convergence on Higher Education Networks

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  1. Data, Voice, and Video Convergence on Higher Education Networks Jim Jokl jaj@Virginia.EDU August, 2000

  2. The TraditionalCampus Network Model • Telephone service • Manages PBX or Centrex, cable plant • Usually self-funded via chargeback • Data network service • Typically part of computing center • Funding models vary widely • Video services • Often distance learning office • Funding sources?

  3. The Converged Multiservices Campus Network Model • Single data, voice, and video infrastructure service • Implications: • Technical • Organizational • Financial • Staff retention and training

  4. Standard Network Applications • Normal services • Web • Email • Remote login • File and print services • These applications function well with a best effort network data delivery model

  5. Newer Converged Network Services • Video Streaming • Video Conferencing • Telephony • These applications function best with a guaranteed network data delivery model

  6. Network Capacity for Video

  7. Broadcast Network Video • Applications • Major events & lecture style classes • Infrastructure needs • Low loss, high capacity, multicast • Systems • Real Networks • Windows Media • Many others

  8. On-Demand Network Video • Applications • Case materials, training, time shifting • Infrastructure needs • Low loss & high capacity • Systems • Real Networks • Windows Media • Many others

  9. Videoconferencing • Applications • Seminar style classes • Travel avoidance • Infrastructure needs • Low latency, low loss, high capacity • Systems • NetMeeting • VCON, PolyComm • Many others

  10. Video Unit Video Unit Video Unit Video Unit MCU Network Videoconferencing: Multi-point Service • Multi-location sessions • Local and remote sites • Video follows speaker (and not) • Products from Cisco, Radvision, White Pine, many others

  11. Video Unit Video Unit Video Unit Campus Network ISDN Gateway Videoconferencing: ISDN Gateway Service • Access legacy systems • Translates: • H.323 <--> H.320 • Applications: • Interviews • Guest speakers • Negotiations • Collaboration Remote Systems

  12. Campus Network Routers, hubs, switches Packet Voice: What is different? Traditional Phone Switch Voice over IP (VoIP) PSTN PSTN Call Manager Gateway Phone Phone Switch Phone Phone Phone Phone Phone

  13. Network Capacity for Packet Voice Services

  14. VoIP Systems: Lots of definitions • PBX VoIP line or trunk card • Call path between IP phones via PBX • Initial releases by Lucent, NEC, others • PBX VoIP line or trunk cards • Call path between IP phones via LAN • Nortel, Siemens, others have systems • Most PBX manufacturers working towards this type of functionality • Major advantage: phone features

  15. VoIP SystemsDefinitions Continued • LAN-based Systems • Call setup via LAN call processing server • Call path between all peripherals via LAN • Cisco Call Manager • Siemens HiNet Xpress • Others • LAN-based systems generally limited • ACD, console, call center applications

  16. Some VoIP Applications • Toll bypass • Low risk • Potentially limited payback • Telecommuting • Phone # tied to phone - not wall jack • DSL or cable modem connection • On-campus telephone replacement • Converged network - many opportunities and issues to consider

  17. Selected Campus VoIP Issues • E911 • Phone # tied to phone - not wall jack • PC-based soft phones • Electrical power and cooling • Phone instruments • Wiring closet UPS units and cooling • Network security • Privacy • Number plans

  18. SIP and H.323 • H.323 Protocol • ITU protocol • Session Initiation Protocol (SIP) • IETF developed as alternative to H.323 • RFC-2543

  19. Network TechnologySupport for Converged Applications • Traditional data applications • Voice • Low latency, loss, jitter • Streaming Video • Low loss and high capacity • Videoconferencing • Low latency, loss, jitter • High capacity

  20. A Campus Network PC Building LAN Building LAN PC PC Video Building LAN Backbone Network Building LAN Building LAN PC Building LAN PC Server Appliance

  21. Standard Ethernet:Intra-Building Network B • Access Mechanism • CSMA/CD • Speed • 10 Million bits/sec • 1 million chars/sec • Bandwidth shared • Applications • Email, Web, telnet, directory, printing, file systems, etc C E F A D

  22. 100 Mbps Switched Ethernet Intra-building Network • Speed • 100 Million bits/sec • 10 million chars/sec • Bandwidth additive • Applications • Email, Web, telnet, printing, file systems, video, voice, etc • May supportConverged Net - even at 10Mbps Network Switch E C B A D F

  23. Network Quality of Service (QoS) • Goal: provide better service for some • Characteristics of QoS • provide guaranteed or priority delivery • minimize delivery delay • minimize delay variations • provide consistent data throughput capacity

  24. QoS: Some Mechanisms • Overbuild the network • RSVP - reserve network capacity • Applications request QoS services • Network says yes/no • Policy • Available resources • Network busy signal • State maintained at each network hop • Relatively complex

  25. QoS: Some Mechanisms • Per-hop mechanisms • Precedence bits in IP TOS byte • Differentiated Services - RFC-2475 • Traffic classified as it enters the network • Per-hop behavior based on classification • All state is in the packet header • Framework for how to cross admin boundaries • Relatively simple

  26. QoS: Some Mechanisms • Layer 2 Mechanisms • 802.1Q - VLAN Tagging • 802.1p Class of Service field of the 802.1Q tag • Implementation • Queue management • Packet scheduling

  27. Switched NetworkWallJack IP Phones and QoS • IP phone generates 802.1p CoS = 5 and IP precedence = 5 • Switch in phone can clear PC’s QoS header settings • Different VLANs for phone and PC IP Phone Personal Computer

  28. Multicast Support Video Server PC LAN Switch Building LAN PC PC PC Hub Building LAN Backbone Network P1 P2 P3 Building LAN Building LAN PC Building LAN P4 PC PC

  29. Network ReliabilityWhat about all of those 9s? • PBX: 99.999% uptime • Down 5.25 minutes/year • Is your data network ready to support life safety applications? • Network Management • Redundancy • Response time and coverage

  30. Converged Networks Infrastructure Summary • Consider wiring closet switches with • 10/100 Mbps • 802.1p and 802.1Q support • IGMP snooping • Support QoS mechanism in network core • Support multicast in network core • Wiring closet UPS power and cooling? • Management for network availability • Different response times and service levels?

  31. Wireless CommunicationPromise of the future • Convergence • Voice, data, video, applications • Integration • Ubiquitous access • New wireless technologies will address much • but be careful of the hype

  32. Wireless Technologyby Coverage Area • Personal Area Networks • 10 cm to 10 meters • Microcellular • 10 meters to 200 meters • Cellular • Large and small cells • Hundreds of meters to miles • Long distance

  33. Personal Communication Services (PCS) • Targeted Services • Cellular telephone users • Paging • Short Messaging Service (SMS) • Nation-wide services • Some technologies: modem-speed data

  34. PCS Technology • Cellular: varies but can be miles • Microcellular within buildings • 1.9 GHz band (licensed) • Digital transmission • Embedded devices: phones, PDAs, etc

  35. PCS Technology • CDMA (Sprint, PrimeCo, Intelos) • Voice, text messaging, paging • Low-speed data • Hospital power levels • TDMA (SunCom, AT&T) • Voice, text messaging, paging • Data harder to handle • High-power hand sets

  36. Wireless LAN SystemsIEEE 802.11 • Targeted Services • Notebook PC users and PDAs • Hard to wire locations • Changing environments • Temporary networks • Campus-wide networks

  37. Wireless LAN SystemsIEEE 802.11 • Technology (now) • Microcellular (250 to1,200 feet) • 2.4 GHz band • Speed: 1 to 11 Mbps • Power: 100 mW • Privacy: inherent and WEP • Technology (future) • 802.11a @ 5 GHz • Speed: 6 to 54 Mbps

  38. Wildcard: BluetoothPersonal Area Network • Targeted Services • Wireless headset / speakerphone • Synchronization of PDAs, notebooks, phones • Cable elimination • Speed around 721 kbps + voice • 2.4 GHz band

  39. Wireless Convergence • Data on wireless voice network • Modem-speed data via PCS • Messaging, WAP, PCS • Soon to be much faster • Voice on wireless data network • Symbol • SpectraLink • Opinion: the biggest challenge to LAN-based VoIP - one phone, one number

  40. Organizational Issues • Integrated data, voice, video groups • Departmental LANs vs Enterprise Networks • Staff development and training • Soft VoIP phones and desktop mgmt? • Wireless Interference • Between unlicensed services • Between central and departmental systems

  41. Converged Network Costs • Will vary widely by campus • Consider: • Wiring closet UPS power • Additional wiring closet cooling • Edge 10/100 switches with 802.1p and Q • A new network core • Increase network support - life safety • VoIP • Equipment - not 2x PBX

  42. Financial Models • Converged networks, especially VoIP, break most existing funding models • What to bill for • Wall outlet? • MAC Address? • IP phone or soft phone? • A tax based on headcount or NASF? • Go for broke: central funding?

  43. Summary: Items to consider • Solve organizational issues • Integrate central data, voice, and video staff • Resolve ownership of building LANs • “Ownership” of campus wireless spectrum • Who gets benefits from easements? • Pay special attention to staff • Pay attention to network technology decisions • Find a long term financial model

  44. Summary: Items to consider • Socialize the issues now • Don’t promise to save money • Toll bypass • MAC work • Sell the network on its new services • Make a wireless decision • Upgrade your network • The killer application will come

  45. Observations, questions, issues?

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