Is the Internet Ready for Multimedia? Ahmed Helmy University of Southern California
Is the Internet Ready for Multimedia? What is Multimedia? –Common: Real-time/streaming (audio/video) –More general: Multiple requirements (QoS) by different applications –What are these requirements? End-to-end metrics: Reliability, Delay, Jitter, least cost! Aggregate metrics: Least congestion, maximum utilization, fair, minimum energy! –Is Internet-supported emergency service MM? Need very high priority service
What is the Internet? –Wired –Last hop wireless (cellular, access points, space optics and pico cells) –Mobile (continuous vs. intermittent) –Multi-hop wireless (Ad hoc) –other… ! Different network characteristics provide different challenges for various requirements –Need to understand characteristics of these networks Need models for: topology, traffic, channel, mobility …
Supply vs. Demand Supply –Infrastructure (e.g., ISPs, content providers) –Architecture/protocols IntServ DiffServ Hybrid! –Business and pricing models??? Demand (those who need QoS) –Audio, video, collaborative virtual env. –Multicast Dense-mode, Sparse-model, source-specific Inter-domain? (BGMP) Current: PIM-SM, MDSP, SSM ! –P2P: effect on network –New paradigms Ad hoc/Sensor networks Active networks Demand is a moving target. We need to be flexible and think ahead. What’s the next killer app.?
Are we ready? (Questions) What does QoS mean without end-to-end deployment of IntServ or DiffServ? Can we over-provide resources? –What resources? Bandwidth, computation (servers), energy ! (sensor nets) – Can we over-provide everywhere? Will the solution be a hybrid approach –Over-provisioning when/where possible –QoS architecture otherwise What about DoS attacks? –Need fairness and isolation of misbehavior
Are We Ready? (more Qs) We talk about network-side QoS What about protocol-side QoS? If the network is not congested, can we guarantee protocol behavior? We need better approaches to design predictable protocols –Can we provide a parallel of circuit-design CAD tools?
What about emerging networks? Example: –Multicast in large-scale ad hoc networks –How to rendezvous in an infrastructure-less network? Need to re-think bootstrap and resource discovery Need to re-think routing in a highly dynamic env. Should we think about it when we do not know how to do it in the wired network? –Good intellectual exercise that has potential
Are we ready? (Answer) Of course not We have a lot more work to do!