Towards an Integrated Multimedia Service Hosting Overlay

1. Towards an Integrated Multimedia Service Hosting Overlay Dongyan Xu Xuxian Jiang presented by Alex Li

2. Motivations • Trends • 1. Multimedia data becomes • easier consume and generate by users • more flexible for manipulations • 2. Realtime operations of media streams • scene change detection • object tracking, etc. • Needs media services that • transport • process • analyze

3. MSODA Overview • Based on SPY-Net • Layered, overlay network • Key aspects • Virtualization • Alternative service config suggestion • End-to-end network monitoring • Goals • Resource Utilization • Service Quality • Serivce Composability

4. Three-layer Middleware

5. Service Composition Layer • Service Profile Database • maintains basic services provided by nodes • Provides • APIs for composing basic services • Validity check against profile database • Suggestions based on profiles

6. Service Configuration Layer Service Spec Service Config Layer … Resource-awareness selection from multiple candidate configs Resource Conditions Service Config

7. Resource Awareness • Resource Conservation

8. Resource Awareness • Load Partitioning • Request Aggregation • same media data sharing

9. Service Mapping Layer • Tasks • map services to VMs • route media streams • Overlay Monitoring • mesh maintenance • mesh augmentation via cold connection jumpstart

10. Mesh Maintenance • Similar to link-state routing • Parameters • Tp: neighbor-probing period • Tq: non-neighbor-probing period, >>Tp • Nbr(P): neighbor set of P • dmax(P): max monitoring connections • B(P,P’): probed end-to-end bandwidth between P and P’ • B(P->P’): BW of the path from P to P’ in the mesh

11. Mesh Maintenance • Probe and Propagate • Probe nodes in Nbr(P) every Tp • Propagate results to Nbr(P) at end of Tp • Mesh Adjustment 1. Every Tq, node P probes Px not in Nbr(P) 2. If B(P,Px) <= B(P->Px) no change else if |Nbr(P)| < dmax(P) add Px to Nbr(P) else Given Pv in Nbr(P) U {Px} If Removing (P,Pv) causes least drop compared with B(P,Pv) exclude Pv

12. Mesh Augmentation • Cold-connection jumpstart • Px not in Nbr(P) • (P,Px) is cold • Add to mesh for Tp • Passive connection monitoring • If (P,Px) chosen for service delivery overlay before Tp expires • (P,Px) now warm • P monitors (P,Px) data rate • Turn cold if • no stream uses (P,Px) • stream fails to maintain data rate

13. Evaluation • Simulated with • 16 nodes • 2 other algorithms • Complete graphs • Shortest-widest-path • different dmax(P)

14. Mapping Success Rate * Success rate of SPF w/ mesh aug rivals complete graph

15. Cost-Effectiveness * SPF w/ mesh aug more cost-effective * Lower dmax, same success rate -> highly effective for low dmax

16. Comments and Critique • Pros • Very efficient overlay monitoring technique • Well-defined layered model • Visions on future multimedia transport/processing infrastructure • Cons • Scalability of nodes in experiements • API design and service specifications issues

17. Questions ?