| Javed I. Khan | |
| ACTIVENET PI Meeting , June 2001, Jackson Hole | |
| Networking and Media Communications Research Lab | |
| Dept of Math & Computer Science | |
| Kent State University | |
| Sponsor: DARPA/ITO |
Network Adaptation: A
case study
with scalable video across network asymmetry
| Link Capacity Adaptation | |||
| Splices wide-band links with low capacity links. | |||
| Application aware rate adaptation. | |||
| Greater down-scalability range (4/5th vs. 1/100th) | |||
| Perceptual encoding | |||
| Interactive data compression with perceptual control over where and how quality is compromised. | |||
| Node Capacity Adaptation | |||
| Allows network junction nodes with unequal CPUs to perform rate adaptation. | |||
| Auto-configuration by motion vector bypass | |||
| Reuses motion vector and saves computation for quality | |||
| Cycle sweeping (network spread) | |||
| If one node is not enough it spreads the computation upstream and sweeps additional cycles from active nodes. | |||
Transcoder’s Self-Organizing States
Flow: “Single Stream Multiple Form”
Sensitivity: Spatial SNR Control
Object Tracking in Stream by Inverse Motion Vector Projection
Motion Vector Transformation for Temporal Scalability
DEMO
object tracking in video
Spatial scalability
Temporal scalability
Reflection on Scalable Transcoding
| Scalability=deeper knowledge+system symbiosis | |||
| Rate adaptation at network level? Only 80%. | |||
| We are trying to gain deeper interaction: | |||
| Content protocol aware adaptation (requantization, DCT filtering, etc.) | |||
| Content aware adaptation (object detection based). | |||
| Interactive viewer aware adaptation. | |||
| Active network insight: | |||
| Look at the source of info that forms the base of adaptation? | |||
| video protocol designer | |||
| content producer | |||
| viewer | |||
| above all-- the network resource awareness | |||
| Each knowledge component have their distinct role. How to connecting all the parties involved? | |||
Reflection
Active
Programmable Harness
| We needed two things: | |||
| Collect link and node capacities to find out optimum transcoding points. | |||
| Now set the configuration parameters. | |||
| We consequently designed a network local state collection and propagation tool | |||
| User application sends the propagation and synthesis math, the harness takes care of the propagation by 2.5 phase communication. | |||
| A building block for transcoder deployment in a multicast network. | |||
| A generalization of SNMP | |||
| Instead of P2P it is now graph wide. | |||
| Local composition on local MIB2 elements at active nodes. | |||
Transcoding Tree Determination
Generalized Harness: State Model
Beyond Video: Active Hypermedia Accelerator
| Sits quite at the other end of a narrow link and monitors surfer’s behavior. Accordingly pre-fetches, caches, transcodes, and performs customized stream scheduling. |
Lessons Learned:A Top
Down View
What an adaptive stream might need from active network?
Reflection: Resource Adaptation
| In a large network diversity is ingrained | ||
| Whether it is an adaptive service or not, but the ingredient components should not make very restrictive assumption about network resources. | ||
| This requires certain behaviors (potential “Active Network Layer Services) | ||
| Network resource awareness | ||
| State awareness about the service | ||
| Self-organization help (state maintenance signaling?) | ||
| Plug-in in the applications themselves (footprint). | ||
| Seamless reorganization | ||
| Performance and Onion Peeling: | ||
| Encapsulation does not stop at TCP layer it continues upward… | ||
| [IP[TCP[TS[SEQ[PIC[SLICE[MB]]]]]]] | ||
| Active network have to worry about performance of access. | ||
| To get access to one field-- generally we have to access. somewhere up to 5-10 other fields! Major performance drainage. | ||
| Current protocols = logic + field placement | ||
| Proposal = Separate logical definition from locution in packet. | ||
| Optimum locution based on access dependency of the capsules. | ||
| Active network feels like very crude bare-bone architectures. | ||
| Powerful yet simple construction formalism is critically required to encourage usability of the architecture and reusability of the efforts spent to develop middleware on them. | ||
| Some of our organized thoughts hinting solutions: | ||
| Language to express ‘deployment constraints’. | ||
| Language to express ‘resource requirements’. | ||
| Language to express ‘bounds of adaptation’. | ||
| “Virtual instrument” | ||
| Definitely I am out of time by now! Pl. see our publications. | ||
| Papers are available at http://medianet.kent.edu/ | ||