multimedia services over networks
DESCRIPTION
Multimedia services over networks. Framework/ Architecture. Review/background. Service provider. Multimedia Services Delivery. Bind. Publish. Deployment/ Management. Multimedia system. Service registry. Service client. Discovery. Transactions/ mobility/locations. - PowerPoint PPT PresentationTRANSCRIPT
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Multimedia services over networks
Service provider
Service client
Service registry
Publish
Discovery
BindMultimediasystem
Review/backgroundFramework/Architecture
Deployment/Management
MultimediaServicesDelivery
Transactions/mobility/locations
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Multimedia services delivery
• Zhiwen Yu and Daqing Zhang: Middleware Support for Context-Aware Ubiquitous Multimedia Services. Handbook of Research on Mobile Multimedia. (pdf ).
• Conor Muldoon, Gregory M. P. O'Hare, Rem W. Collier, Donnacha Phelan, Robin Strahan: Intelligent Delivery of Multimedia Content in a Device Aware Ubiquitous Environment. Multimedia Information Systems 2005: 131-145, (pdf)
• Zhou Wang and Hend Koubaa: Discovering Multimedia Services and Contents in Mobile Environments. Handbook of Research on Mobile Multimedia (pdf)
• Ricky Robinson, Jadwiga Indulska: A Context-Sensitive Service Discovery Protocol for Mobile Computing Environments. ICMB 2005: 565-572, (pdf)
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Context-aware multimedia service
• Context information– Time– Location– Device capability– User preferences
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Example
• Stopping vs. moving
SDTm
A B
NTNU, Trondheim
A
B
MC
S
Nb
D
D: Distance of movement S: Speed of mobile hostNb: Wireless bandwidth
M: Amount of data transferedTb: Battery life-time
bs N
MT
Ts < Tm < Tb
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Context Management
ContextAggregation
ContextReasoning
ContextLearning
ContextQuery
Userprofiles
Situation
Query
ServiceClientsContext
Service
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Context representation model
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Context ontology
User situation UserPreference onMedia
Capability of mediaterminal
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Context-aware multimedia architecture
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Intelligent Delivery of Multimedia Content in a Device Aware Ubiquitous Environment• GLIDE
– Generic Language of Interface DEvelopment• Context-aware ubiquitous environments• Enforce a coding structure on the implementation of
interface components– Re-use and Extensibility
• Enable GUI independence– Among interface components– Between interface components and agents
• How?– Avoid object references– Use of agents
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Agents
Clients ServerClient agents Server agents
Specifying the type of device
Adaptive GUI components
• Prevent inter-component dependencies– Decoupling
• Reuse of interface components• Dynamic restructured GUI Pros and Cons
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GLIDE
Hardware•PDAs•CellphonesSoftware•J2ME-CDC•CLDC
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GLIDE framework
• Factories– A class that returns an instance of a particular interface
component
• Interactions– Defines a dependency that a component has on another
component or agent
Composite objectGLIDE Instance GUIcreated
Handling•Interactions
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GLIDE development process
PDAs
Cellphones
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GLIDE grammar
Factory•Which Java class whild be loaded to create service specific GUI componentsInteracts•Define how the composite objects map interactions to entities
•Entities can be components or agents
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Dynamic restructuring GUI
•Resources•User’s behaviors From Interface
To delivery content
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Discovering multimedia services and contents
• Context awareness– When– Where
• Service discovery model– Broadcast– Centralized service directory– Distributed service directories
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Broadcast model
Pull vs Push
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Centralized directory model
1. Locating directory2. Service registration3. Service lookup4. Searching
Examples: JINI, INS
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Distributed service directories
• Service discovery is a service• Interoperability• Asynchronous service discovery• Semantic service discovery
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A Context-Sensitive Service Discovery Protocol for Mobile Computing Environments
• Discovery service– Query preferences
• Allow tailoring query results– Query ranking when multiple resources are matched
• Context-sensitive application– Context-aware– Adjust its behavior when the context changes
• If resource discovery protocols are context-sensitive, then results are dependent upon the context of the query
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Discovery framework
• Persitent queries– Synchronous matching service– Asynchronous newly matching server
• Elvin engine (asynchronous messaging system - should try)
• Transient adversements– Information is meaningful only at the time of advertisement– Results are not stored
• Sub-queries• Named queries
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Context-sensitive query
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Preference model and language
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Application iCarpark
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Application iCarpark - cont
Issues:-Technologies
-Location direction-RFID readers-On-car computers
-Performances