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ADSL PowerPoint Presentation

ADSL

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ADSL

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  1. IP-Multicast over ADSL Brigitta Lange NEC Europe Ltd. C&C Research Laboratories Adenauerplatz 6 D-69115 Heidelberg lange@ccrle.nec.de

  2. Overview • Internet Application Trends • Experiences ADSL Pilot Aachen • Requirements for Multicast Support • Multicast Architectures for ADSL • Multicast Gateway • Multicast over PVC • Performance Results • Field Trial Homelearning over ADSL • Summary

  3. Internet Trends (1)

  4. Internet Trends (2)

  5. Internet Trends (3) Point to Point Point to Multi-Point Multi-Point to Multi-Point

  6. ADSL Pilot Aachen (1) • ADSL Pilot Aachen • Cooperation: RWTH Aachen, DTAG, NEC • launched in February 1998 • currently 700 residential users • Objectives • Test/ Evaluation ADSL Technology • High speed Internet/ remote LAN access • Analysis of User Behavior

  7. ADSL Pilot Aachen (2) • Experiences: user behavior • ADSL encourages multimedia applications • enables high-quality tele-working • growing demand for multimedia collaborative applications: • audio/video conferencing, distributed games • Delimiter for multimedia group applications: • require efficient PMP communication • lack of IP-Multicast support in access network

  8. IP- Unicast Host A Host U Host B Host C Host D IP- Multicast Host A Router Host M Host B Router Router Host C Host D Introduction to IP-Multicasting

  9. Broadband Access Networks • Roll out of ADSL: • bandwidth no longer delimiter • delivery of broadband services to the homes • Success of ADSL networks: • depends on high bandwidth applications • Network infrastructure has to support emerging services • Multicast is essential for these applications • IP-Multicast support is a key requirement for broadband access networks

  10. Customer Premises CO Central Office Regional Broadband Network Wide AreaNetwork Content Provider CorporateNetwork ONU ONU Access Node ONU ONU ISP Internet Backbone Multimedia Server ONU ONU ONU: Optical Network Unit ATU: ADSL Termination Unit ATU ATU ATU ADSL Network Architecture

  11. ADSL Network Scenarios • PPP over ATM over ADSL: • PPP provides Authentication Accounting, Address assignment • ATM provides QoS guarantee • Connection between End-user and NSP: • by ATM PVCs or by ATM SVCs • In near future only PVCs will be available • Goal: Provide IP-Multicast in this scenario • short-term solution based on PVCs

  12. Requirements for IP-Multicast Support over ATM/ADSL • Key aspects: • scalability (# of clients, # of groups) • efficiency of data replication • avoid broadcasting all multicast groups • support for dynamic joining and leaving • accounting facilities • Additional aspects: • QoS • implementation effort • smooth PVC -> SVC migration

  13. Multicast Architectures for ADSL • Multicast Gateway (short-term solution) • Multicast client-server application • access through Unicast tunnels • Multicast over PVC (mid-term solution) • based on MARS/MCS • Multicast in PVC based access networks • MARS/MCS (long-term solution) • IETF proposed standard • good scalability, based on SVCs

  14. Multicast Gateway (1) • Architecture:

  15. Multicast Gateway (2) • Performance Measurements

  16. Multicast Gateway (3) • Advantages • immediate realization • easy implementation • Disadvantages • no real multicast: ADSL client has to install special software • inefficient: replication of packets at application layer (end user space) • not scalable with number of clients

  17. Multicast over PVC (1) • Adress resolution: MARS • Replication/Forwarding: MCS • Two approaches for data forwarding: • Multiple PP PVCs from MCS to each host: • selective sending to hosts joined • replication done at the network level (kernel) • PMP PVC to all hosts of cluster: • broadcast to all hosts, non-selective • efficient: replication done at the ATM level • flooding of users accesses with useless traffic

  18. MARS PP PVC IP-MC-Group ATM-Address MRouter MCS MARS MRouter PMP PVC MCS Multicast over PVC (2)

  19. Performance Comparison • Bandwidth supported without losses for the different Multicast Architectures: • Result: Multicast over PVC more efficient • supports larger number of end users

  20. DFN Project ANETTE • ANETTE : Applications and NEtwork Technology for Teleteaching • joint proposal of the universities of Mannheim, Freiburg, Aachen and NEC • funded by DFN (Germ. Research Network) • project duration: June 1999 - May 2001 • ATM/ADSL Field Trial for advanced Homelearning and Teleteaching scenarios • Testbed for the proposed Multicast Architectures, scalability studies

  21. Heidelberg Karlsruhe Freiburg Mannheim Aachen ANETTE Scenario Home Students Aachen ADSL B-WIN DFN Lecture Hall Universities Home Students Mannheim ISDN

  22. ANETTE: ADSL Trial Aachen StudentsHome CO Central Office RWTH Aachen 1 UniversityBackbone ATM Backboneof B-Win ATU 1 : ONU ONU 24 MCRouter 1 ATMXSwitch 2 ADSL Multicast Access Server ATU : ONU ONU ADSL Multicast Access Server 24 1 : 3? ONU ONU ATU 24 Uni Mannheim,...

  23. ANETTE: Teleteaching Tools Video Whiteboard Import Whiteboard Audio Control

  24. Summary • Growing demand for multimedia group applications based on point-to-multipoint communication • IP-Multicast support in RBB networks needed • Two step proposal for ATM/ADSL networks: • Multicast Gateway (short term) • Multicast over PVC (mid-term, more efficient) • Evaluation of both architectures in ADSL field trial for Interactive Homelearning scenarios