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Guaranteed services in heterogeneous wireless access networks

Guaranteed services in heterogeneous wireless access networks. Giulio Iannello Università Campus Bio-Medico di Roma. Who we are. Università Campus Bio-Medico di Roma: young institution borne in 1993 around a Faculty of Medicine

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Guaranteed services in heterogeneous wireless access networks

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  1. Guaranteed services in heterogeneous wireless access networks Giulio Iannello Università Campus Bio-Medico di Roma Wide-scalE, Broadband, MIddleware for Network Distributed Services

  2. Who we are • Università Campus Bio-Medico di Roma: young institution borne in 1993 around a Faculty of Medicine • In 1999 started a Faculty of Engineering with a course in Biomedical Engineering • Tight integration between the two Faculties • Fields of interest: informatics, system modeling, biomaterials, biomedical instruments, robotics Wide-scalE, Broadband, MIddleware for Network Distributed Services

  3. Who we are • Research group on Computer Networks and Advanced Distributed Applications • COFIN project: Scalability and Quality of Service in Web Systems (closed) • FIRB project: Wide-scalE, Broadband, MIddleware for Network Distributed Services (active) • Hospital Information System for Students (HISS) project funded by Hewlett-Packard (active) Wide-scalE, Broadband, MIddleware for Network Distributed Services

  4. Who we are • Contributors: • Filippo Cacace • Maria Cinque • Michele Crudele • Stefano Za • Massimo Bernaschi (CNR IAC) • Pierluigi Salvo Rossi (Napoli Federico II, DIS) • Luca Vollero (Napoli Federico II, DIS) Wide-scalE, Broadband, MIddleware for Network Distributed Services

  5. Motivations • Making Internet services accessible anywhere, anytime, anyhow, and by anyone is a research field that emerged recently • W3C Device Independence (DI) Activity focuses on making Web accessible anytime and anyhow • many access mechanisms (including mobile devices) • many modes of use (including multimedia ones) Wide-scalE, Broadband, MIddleware for Network Distributed Services

  6. Motivations • DI can be considered from three perspectives: • user • authoring techniques • delivery mechanisms • Our activity focuses mainly on the third item and concerns system support to service guarantees in the Device Independence vision Wide-scalE, Broadband, MIddleware for Network Distributed Services

  7. Motivations Delivery mechanisms perspective Wide-scalE, Broadband, MIddleware for Network Distributed Services

  8. Motivations • The delivery subsystem should be able to reserve resources needed to deliver services in a highly dynamic environment • Our activity on these “traditional” Quality of Service issues is currently focused on: • heterogeneous wireless access networks • dynamic changes in network configuration and workload Wide-scalE, Broadband, MIddleware for Network Distributed Services

  9. Motivations • Service adaptation: a complementary concept to provide effective support to universal access: • Adaptation to access media • bandwidth, reliability, security • Adaptation to the interface (terminal device) • screen, power consumption, computing power • Adaptation to the context • localization, time, other circumstances, preferences Wide-scalE, Broadband, MIddleware for Network Distributed Services

  10. QoS support in 802.11 • Supporting traffic differentiation in 802.11 WLAN (infrastructured configurations) • layer 3 management for downstream traffic • for upstream traffic we have proposed a minor modification to MAC protocol at the base station (called Frame Dropping) • can be implemented at firmware level, no change required to mobile stations Wide-scalE, Broadband, MIddleware for Network Distributed Services

  11. QoS support in 802.11 if ACKs are dropped, the MS perceives channel congestion MS increase its CW and this induces traffic differentiation Wide-scalE, Broadband, MIddleware for Network Distributed Services

  12. QoS support in 802.11 Channel utilization (saturation) Wide-scalE, Broadband, MIddleware for Network Distributed Services

  13. QoS support in 802.11 Comparison with DFS (CBR flows) Overall channel utilization (CBR flows) Wide-scalE, Broadband, MIddleware for Network Distributed Services

  14. QoS support in 802.11 • Forthcoming standard 802.11e • advanced protocol with enhanced scheduling mechanisms at MAC layer • performance modeling of throughput and delay in saturation and non saturation conditions (Luca Vollero visiting Albert Banchs/Madrid—Carlos III) • medium term goal: strategies for on-line configuration of MAC parameters Wide-scalE, Broadband, MIddleware for Network Distributed Services

  15. Mobility and seamless connectivity • Integration of WLANs and 2.5G/3G cellular networks • Loosely-coupled approach: Mobile IPv6 • Focus on multi-homed mobile hosts: vertical handoff • seamless and efficient handoffs • handoff policies • cooperative multi-homed connectivity Wide-scalE, Broadband, MIddleware for Network Distributed Services

  16. Mobility and seamless connectivity • IPv6 Mobility Testbed • Operative at Campus Bio-Medico Wide-scalE, Broadband, MIddleware for Network Distributed Services

  17. Mobility and seamless connectivity • Vertical handoff performance improvement • Performance analysis of transport protocols during handoffs • TCP • UDP/RTP • Intelligent handoffs through rule-based management • merging of preferences and other context information Wide-scalE, Broadband, MIddleware for Network Distributed Services

  18. Mobility and seamless connectivity handoff vs. offered workload forced handoff (WLAN  3G) Wide-scalE, Broadband, MIddleware for Network Distributed Services

  19. Adaptive streaming • CC/PP capable clients and web servers • Intel CC/PP framework, Java-based adaptation modules • Profile Resolution Engine (DICO—UNIMI) • on-line assessment of network performance • Transcoding modules • algorithms for trading-off reproduction quality and bitrate • real-time multimedia processing (RT-MMP) toolkit • Adaptive RTP server Wide-scalE, Broadband, MIddleware for Network Distributed Services

  20. Adaptive streaming Intel CC/PP framework Wide-scalE, Broadband, MIddleware for Network Distributed Services

  21. Adaptive streaming Profile’s repository Web Server HTTP Request + CC/PP Profile HTTP Response Client 1. Client Profile learning 10. A connection via RTP is estabilished for the streaming video 5. This servlet retrives client’s info, from repository, to know its constrains 4. After client’s choice, the server calls the Adapter Engine 3. The server replies to the client with an adapted web page in which there is movies’ list • The device requests a web page via HTTP • Using CC/PP, it sends also its infos 8.This infos are sent to the Adapter 2. The web server (CC/PP aware) supplies to load device’s profile into a DB 7.The Video Server sendes “probe traffic” to the client to know the network’s status 6.The servlet now has to contact the “right” Video Server, supplying to it client’s ID 9. Now the Adapter Engine determines the bottelneck and how to adapt the video (degradator factor) Probing Adapter engine (servlet) 2. Environment learning RTP 3. Info merging Video Server + degradator Wide-scalE, Broadband, MIddleware for Network Distributed Services

  22. Thank you Questions? End Wide-scalE, Broadband, MIddleware for Network Distributed Services

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