Project Number: / IST – 2001 – 38142 – CONTEXT
Project Title: / Active Creation, Delivery and Management of Efficient Context Aware Services
Design and Implementation of Components for the Proof of Concept of Provisioning and Management of Context Aware Services
Editor: / TID
Document Id: / Context-WP3-TID-D3.2
File Name: / CONTEXT-WP3-TID-D3.2-Final300904.doc
Version: / 8.1
Organization: / TID
Date: / 30 September30th October 2004
Document type: / Deliverable
Security: / CO
Abstract:
This document aims to present part of the results of the work carried out in CONTEXT WP3 “Context-aware Service Layer” in close collaboration with WP2 “System Concepts and Overall Architecture” and WP4 “Active Application Layer”.
The overall system architecture is mapping into a computational, ready to implement architecture, where the identified functional components are decomposed into smaller components and mapped into appropriate computational entities.
Keyword list: Context-aware Services, Service Layer, Active Application Layer, DINA
Copyright 2004 CONTEXT Consortium
-1-
CONTEXT-WP3-D3.2
Contributors
Name / ContributionsVTT Technical Research Centre of Finland, Information Technology / Contribution on Chapter 15 "Super Mother Scenario"
Telefónica Investigación y Desarrollo S.A Unipersonal / Main editor
Chapter 1 "Introduction"
Chapter 12 "Service Assurance"
Chapter 16 "Crisis Helper Scenario"
Chapter 18 "Conclusions"
Contribution on section 9.1.3.4 "AC Data API"
Executive Summary
VODAFONE-PANAFON Hellenic Telecommunications Company S.A.
ALGONET S. A. / Chapter 2 "CONTEXT Service Layer Architecture"
Chapter 3 "Automating the Process of Service Introduction"
Chapter 4 "CAS Modelling"
Chapter 5 "CAS Authoring"
Chapter 6 "CAS Customization"
Chapter 7 "Code and Policies Generation Engine"
Chapter 13 "Executing CAS in the DINA Active Network Platform"
University College of London / Chapter 10 "Code Distributor"
Chapter 15 "Super Mother Scenario"
TECHNION Israel Institute of Technology / Chapter 11 "Code Execution Controller and Service Invocation Listeners"
Universitat Politècnica de Catalunya / Chapter 8 "Policy-Based Service Management System"
Chapter 9 "Policy-Based Management Paradigm in Context"
Annex A "Global Information Model"
Institute of Communication and Computer Systems, National Technical University of Athens / Chapter 14 "Context Information Handling Mechanism"
Chapter 17 "Moving Campus Economy Scenario"
DOCUMENT HISTORY
Date / Version / Status / Comments06.04.2004 / 1 / Draft / ToC
08.04.2003 / 2 / Draft / Chapters 8 & 9 (UPC).
25.04.2003 / 3 / Draft / Chapters 1, 12, 16 & 18 (TID).
Annex A (UPC)
Update of chapters 8 & 9 (UPC).
Chapters 14 & 17 (NTUA).
27.04.2003 / 4 / Draft / Section 9.1.3.4 'AC Data API' (TID).
Chapters 2, 3, 4, 5, 6, 7 & 13 (ALGONET)
Chapter 10 (UCL)
Chapter 11 (TECHNION)
28.04.2003 / 5 / Draft / Chapter 15 (UCL)
Chapter 16 (TID)
Update of chapter 10 (UCL)
27.05.2004 / 6 / Draft / Updates of all chapters
28.09.2004 / 7 / Draft / Executive Summary
Updates of all chapters
30.09.2004 / 8 / Final / Revised
30.10.2004 / 8.1 / Released / Reviewed and Approved
Copyright CONTEXT Consortium: VTT Information Technology, Telefónica Investigación y Desarrollo S.A Unipersonal, VODAFONE-PANAFON Hellenic Telecommunications Company S.A., ALGONET S. A., University College of London, TECHNION Israel Institute of Technology, Universitat Politècnica de Catalunya, Institute of Communication and Computer Systems/National Technical University of Athens.
TABLE OF CONTENTS
1introduction......
2CONTEXT service layer architecture......
2.1Overview of CONTEXT project and its architectural aspects......
2.2Major functional blocs of the Service Layer......
2.3Service Layer Architecture......
2.4Interfaces between components......
3automating the process of service introduction......
4CAS ModeLling......
4.1Rational and approach......
4.2The basic modules for defining CAS......
4.3CAS Model......
4.4Service Definition Document......
4.4.1CAS Model Instantiation......
4.4.2ºModelling the logic......
4.5Using CAS for creating new CAS......
5cas authoring......
5.1Functional Overview......
5.2Functional Decomposition......
5.3External Interfaces......
5.4Internal Interfaces......
5.5Engineering Considerations......
6CAS CUSTOMIZATION......
6.1Functional Overview......
6.2Functional Decomposition......
6.3External Interfaces......
6.4Internal Interfaces......
6.5Engineering Considerations......
7code and policies generation engine......
7.1Functional Overview......
7.2Functional Decomposition......
7.3External Interfaces......
7.4Internal Interfaces......
7.5Engineering Considerations......
8Policy-based Service Management System......
8.1Introduction......
8.2Functional Overview......
8.3Policy Structure......
8.3.1Policy_Set_Id – Policy Set Identification Element......
8.3.2Policy_Group_Id – Policy Group Identification Element......
8.3.3Policy_Id – Policy Identification Number Element......
8.3.4Policy_Aim – Policy Objective Element......
8.3.5IsAtomic – Atomicity Definition Element......
8.3.6Policy_Sequence_Position – Policy Sequence Element......
8.3.7Validity_Period – Validity Period Element......
8.3.8Condition – Condition Element......
8.3.9Enforcement_Sequence – Action Enforcement Sequence Element......
8.3.10Action – Action Element......
8.4Functional Decomposition......
8.4.1Policy Manager (PM)......
8.4.2Decision Making Component (DMC)......
8.4.3Policy & Information Model Repository......
8.4.4Policy Conflict Resolution......
8.4.5Action Consumers......
8.4.6Condition Evaluators......
8.5Interfaces......
8.5.1Introduction......
8.5.2POLICY DEFINITION SYSTEM – POLICY MANAGER INTERFACE......
8.5.3POLICY MANAGER–ACTION CONSUMER INTERFACE (PM-AC)......
8.5.4DECISION MAKING COMPONENT–CONDITION EVALUATORS INTERFACE (DM-CE)....
8.5.5POLICY MANAGER – DECISION MAKING COMPONENT INTERFACE......
8.5.6POLICY & MANAGEMENT INFORMATION MODEL REPOSITORY INTERFACE......
8.5.7POLICY CONFLICT RESOLUTION INTERFACE......
9Policy-based Management Paradigm in CONTEXT......
9.1Rationale – Automating the Process of Service Provisioning......
9.1.1Why Policies?......
9.1.2Objectives......
9.1.3CONTEXT Policy-Based Service Management System......
9.2Domain-specific Policies......
9.2.1Service Code Distribution Policies......
9.2.2Service Code Maintenance Policies......
9.2.3Service Code Invocation and Execution Policies......
9.2.4Service Assurance Policies......
10Code Distributor......
10.1Code Distributor Action Consumer API......
11Code Execution ContROLLER AND Service Invocation Listeners......
11.1Code Execution Controller API......
11.2Service Invocation Listeners......
11.2.1The WLAN SICE......
12Service Assurance......
12.1Functional Overview......
12.2Functional Decomposition......
12.2.1Service Monitoring......
12.2.2Service Management Actions......
12.2.3External Interfaces......
12.3Internal Interfaces......
12.3.1Engineering Considerations......
13Executing CAs in the DINA Active Network Platform......
13.1DINA based execution environment......
13.2CAS code Design......
14Context Information Handling Mechanism......
14.1Introduction......
14.2Functional Overview......
14.3Functional Decomposition......
14.3.1Query Handler......
14.3.2Event Handler......
14.3.3Registration Handler......
14.3.4Storage Handler......
14.3.5External Context Resolver......
14.4External Interfaces......
14.5Internal Interfaces......
14.6Engineering Considerations......
15Super Mother Scenario......
15.1Scenario Overview......
15.1.1Identification of context information......
15.2Testbed and Service Layer Set-up......
15.3Specification of CAS and Management Policies......
15.3.1Code Distribution......
15.3.2Service Invocation and Code Execution......
15.3.3Service Assurance......
16Crisis Helper Scenario......
16.1Scenario overview......
16.1.1Identification of context information......
16.2Testbed and Service Layer set-up......
16.3Specification of CAS and Management policies......
16.3.1Code Distribution......
16.3.2Service Invocation and Code Execution......
16.3.3Service Assurance......
16.4Sequence of Interactions......
16.4.1Description of the sequence of interactions......
16.4.2SICEs, SLOs and CCOs......
17Moving Campus Scenario......
17.1Scenario Overview......
17.1.1CA-Conference Set Up......
17.1.2CA-Announcement Service......
17.1.3Identification of context information......
17.2Testbed and Service Layer Set-up......
17.3Specification of CAS and Management Policies......
17.3.1Code Distribution......
17.3.2Service Invocation and Code Execution......
17.3.3Service Assurance......
17.4Sequence of Interactions......
17.4.1Description of the sequence of interactions......
17.4.2SICEs, CCOs and Actions......
18Conclusions......
19Issues for Further Investigation......
1introduction...... 13
2CONTEXT service layer architecture...... 13
2.1Overview of CONTEXT project and its architectural aspects...... 13
2.2Major functional blocs of the Service Layer...... 13
2.3Service Layer Architecture...... 14
2.4Interfaces between components...... 18
3automating the process of service introduction...... 21
4CAS ModeLling...... 23
4.1Rational and approach...... 23
4.2The basic modules for defining CAS...... 23
4.3CAS Model...... 25
4.4Service Definition Document...... 28
4.4.1CAS Model Instantiation...... 28
4.4.2Modelling the logic...... 28
4.5Using CAS for creating new CAS...... 30
5cas authoring...... 30
5.1Functional Overview...... 30
5.2Functional Decomposition...... 31
5.3External Interfaces...... 33
5.4Internal Interfaces...... 33
5.5Engineering Considerations...... 33
6CAS CUSTOMIZATION...... 33
6.1Functional Overview...... 33
6.2Functional Decomposition...... 35
6.3External Interfaces...... 36
6.4Internal Interfaces...... 36
6.5Engineering Considerations...... 37
7code and policies generation engine...... 37
7.1Functional Overview...... 37
7.2Functional Decomposition...... 39
7.3External Interfaces...... 40
7.4Internal Interfaces...... 40
7.5Engineering Considerations...... 40
8Policy-based Service Management System...... 40
8.1Introduction...... 40
8.2Functional Overview...... 41
8.3Policy Structure...... 42
8.3.1Policy_Set_Id – Policy Set Identification Element...... 43
8.3.2Policy_Group_Id – Policy Group Identification Element...... 43
8.3.3Policy_Id – Policy Identification Number Element...... 43
8.3.4Policy_Aim – Policy Objective Element...... 43
8.3.5IsAtomic – Atomicity Definition Element...... 44
8.3.6Policy_Sequence_Position – Policy Sequence Element...... 44
8.3.7Validity_Period – Validity Period Element...... 44
8.3.8Condition – Condition Element...... 44
8.3.9Enforcement_Sequence – Action Enforcement Sequence Element...... 49
8.3.10Action – Action Element...... 50
8.4Functional Decomposition...... 53
8.4.1Policy Manager (PM)...... 53
8.4.2Decision Making Component (DMC)...... 54
8.4.3Policy & Information Model Repository...... 58
8.4.4Policy Conflict Resolution...... 58
8.4.5Action Consumers...... 58
8.4.6Condition Evaluators...... 59
8.5Interfaces...... 59
8.5.1Introduction...... 59
8.5.2POLICY DEFINITION SYSTEM – POLICY MANAGER INTERFACE...... 61
8.5.3POLICY MANAGER–ACTION CONSUMER INTERFACE (PM-AC)...... 63
8.5.3.1POLICY MANAGER ACTION CONSUMER (PM_to_AC)...... 63
8.5.3.2POLICY MANAGER ACTION CONSUMER (AC_to_PM)...... 65
8.5.4DECISION MAKING COMPONENT–CONDITION EVALUATORS INTERFACE (DM-CE)..67
8.5.4.1DECISION MAKING COMPONENT CONDITION EVALUATORS (DM_to_CE)...... 67
8.5.4.2DECISION MAKING COMPONENT CONDITION EVALUATORS (CE_to_DM)...... 71
8.5.5POLICY MANAGER – DECISION MAKING COMPONENT INTERFACE...... 72
8.5.6POLICY & MANAGEMENT INFORMATION MODEL REPOSITORY INTERFACE...... 73
8.5.7POLICY CONFLICT RESOLUTION INTERFACE...... 74
9Policy-based Management Paradigm in CONTEXT...... 76
9.1Rationale – Automating the Process of Service Provisioning...... 76
9.1.1Why Policies?...... 76
9.1.2Objectives...... 76
9.1.3CONTEXT Policy-Based Service Management System...... 77
9.1.3.1Code Distributor Action Consumer...... 80
9.1.3.2Code Execution Controller Action Consumer...... 81
9.1.3.3Service Assurance Action Consumer...... 81
9.1.3.4AC Data API...... 81
9.1.3.5Code Distributor Condition Evaluator...... 86
9.1.3.6Service Invocation Condition Evaluator...... 86
9.1.3.7Service Assurance Condition Evaluator...... 87
9.1.3.8Policy & Information Model Repository...... 87
9.1.3.9Code Storage Points...... 87
9.2Domain-specific Policies...... 87
9.2.1Service Code Distribution Policies...... 88
9.2.1.1Service Deployment Policies Group example...... 88
9.2.2Service Code Maintenance Policies...... 89
9.2.2.1Service Maintenance Policy Group Example...... 89
9.2.3Service Code Invocation and Execution Policies...... 90
9.2.3.1Service Execution Policy Group Example...... 91
9.2.4Service Assurance Policies...... 92
9.2.4.1Service Assurance Policy Group Example...... 92
10Code Distributor...... 93
10.1Code Distributor Action Consumer API...... 93
11Code Execution ContROLLER AND Service Invocation Listeners...... 94
11.1Code Execution Controller API...... 94
11.2Service Invocation Listeners...... 95
11.2.1The WLAN SICE...... 95
12Service Assurance...... 95
12.1Functional Overview...... 95
12.2Functional Decomposition...... 97
12.2.1Service Monitoring...... 97
12.2.2Service Management Actions...... 100
12.2.3External Interfaces...... 100
12.3Internal Interfaces...... 103
12.3.1Engineering Considerations...... 103
13Executing CAs in the DINA Active Network Platform...... 103
13.1DINA based execution environment...... 103
13.2CAS code Design...... 104
14Context Information Handling Mechanism...... 105
14.1Introduction...... 105
14.2Functional Overview...... 106
14.3Functional Decomposition...... 107
14.3.1Query Handler...... 108
14.3.2Event Handler...... 109
14.3.3Registration Handler...... 109
14.3.4Storage Handler...... 109
14.3.5External Context Resolver...... 109
14.4External Interfaces...... 110
14.5Internal Interfaces...... 114
14.6Engineering Considerations...... 116
15Super Mother Scenario...... 117
15.1Scenario Overview...... 117
15.1.1Identification of context information...... 118
15.2Testbed and Service Layer Set-up...... 118
15.3Specification of CAS and Management Policies...... 119
15.3.1Code Distribution...... 120
15.3.1.1Events...... 120
15.3.1.2Conditions...... 120
15.3.1.3Actions...... 120
15.3.1.4Condition – Action Association...... 121
15.3.2Service Invocation and Code Execution...... 122
15.3.2.1Events...... 122
15.3.2.2Conditions...... 122
15.3.2.3Actions...... 123
15.3.2.4Condition – Action Association...... 124
15.3.3Service Assurance...... 124
15.3.3.1Variables...... 124
15.3.3.2Condition...... 124
15.3.3.3Action...... 124
16Crisis Helper Scenario...... 125
16.1Scenario overview...... 125
16.1.1Identification of context information...... 125
16.2Testbed and Service Layer set-up...... 126
16.3Specification of CAS and Management policies...... 126
16.3.1Code Distribution...... 126
16.3.1.1Events...... 127
16.3.1.2Conditions...... 127
16.3.1.3Actions...... 127
16.3.1.4Condition – Action Association...... 128
16.3.2Service Invocation and Code Execution...... 128
16.3.2.1Events...... 128
16.3.2.2Conditions...... 129
16.3.2.3Actions...... 129
16.3.2.4Condition – Action Association...... 130
16.3.3Service Assurance...... 130
16.3.3.1Events...... 130
16.3.3.2Conditions...... 130
16.3.3.3Actions...... 130
16.3.3.4Condition – Action Association...... 131
16.4Sequence of Interactions...... 131
16.4.1Description of the sequence of interactions...... 131
16.4.2SICEs, SLOs and CCOs...... 133
17Moving Campus Scenario...... 134
17.1Scenario Overview...... 134
17.1.1CA-Conference Set Up...... 134
17.1.2CA-Announcement Service...... 134
17.1.3Identification of context information...... 134
17.2Testbed and Service Layer Set-up...... 135
17.3Specification of CAS and Management Policies...... 135
17.3.1Code Distribution...... 135
17.3.1.1Events...... 136
17.3.1.2Conditions...... 136
17.3.1.3Actions...... 136
17.3.1.4Condition – Action Association...... 137
17.3.2Service Invocation and Code Execution...... 138
17.3.2.1Events...... 138
17.3.2.2Conditions...... 139
17.3.2.3Actions...... 139
17.3.2.4Condition – Action Association...... 140
17.3.3Service Assurance...... 140
17.3.3.1Events...... 140
17.3.3.2Conditions...... 141
17.3.3.3Actions...... 141
17.3.3.4Condition – Action Association...... 141
17.4Sequence of Interactions...... 141
17.4.1Description of the sequence of interactions...... 141
17.4.1.1CA-Conference Set Up...... 141
17.4.1.2CA-Announcement Service...... 143
17.4.2SICEs, CCOs and Actions...... 144
18Conclusions...... 148
19Issues for Further Investigation...... 149
TABLE OF FIGURES
Figure 1: Service Layer major functional areas
Figure 2: Service Layer functional architecture
Figure 3: Service Layer components’ interfaces
Figure 4: Introducing Services
Figure 5: Comparison of CAS introduction infrastructure with the Java programming infrastructure
Figure 6: Generic Module Model
Figure 7: XML Schema implementing the module model
Figure 8: Combination of modules
Figure 9: XML Schema implementing the CAS model
Figure 10: CAS logic example
Figure 11: XML Schema implementation of Policy Based Logic Type
Figure 12: CAS Authoring component functionality
Figure 13: CAS Authoring component functional decomposition
Figure 14: Service Customisation component functionality
Figure 15: Service Customisation component’s functional decomposition
Figure 16: Code and Policies Generation Engine component functionality
Figure 17: Code and Policies Generation Engine functional decomposition
Figure 18: Policy-Based Management System
Figure 19: CONTEXT-General Policy Structure
Figure 20: Validity Period Element Structure
Figure 21: Condition Element Structure
Figure 22: Action Element Structure
Figure 23: Overall Policy Schema
Figure 24: Policy Condition Evaluation
Figure 25: Interfaces between components
Figure 26: Basic Component Interactions
Figure 27: Policies Message Structure
Figure 28: Policy Manager – Action Consumer Interface
Figure 29: Policy Manager to Action Consumer message structure
Figure 30: Action Consumer to Policy Manager message structure
Figure 31: Decision Making Component – Condition Evaluators Interface
Figure 32: Decision Making to Condition Evaluator message structure
Figure 33: Condition Evaluator to Decision Making component message structure
Figure 34: Policy Manager – Decision Making Component interface
Figure 35: Information Repository interface
Figure 36: Policy Conflict Resolution Interface
Figure 37: First approximation of the generic policy-based management system to the CONTEXT service layer functional requirements
Figure 38: IST-CONTEXT Policy-Based Service Management Layer Architecture
Figure 39: IST-CONTEXT Policy-Based Service Management Layer Architecture
Figure 40:Flow Diagram
Figure 41: SLO Execution Environment (EE)
Figure 42: Context Information Dissemination System (CIDS)
Figure 43: Context Broker Architecture
Figure 44: Testbed Architecture for the Super Mother Scenario
Figure 45: The testbed for the Crisis Helper Scenario
Figure 46: Sequence of interactions of Crisis Helper service during execution
Figure 47: The testbed for the Moving Campus Economy Scenario
Figure 48: CA-Conference Setup Service
Figure 49: CA-Announcement Service
Figure 50: CONTEXT Policy Information Model
TERMS AND ACRONYMS
AAL / Active Application LayerAN / Active networks
API / Advanced Programming Interfaces
CAS / Context-aware Service
CB / Context Broker
CCO / Context Computational Object
CDS / Context Dissemination Scheme
CI / Context Info
CIDS / Context Information Dissemination System
CIS / Context Information Source
EE / Execution Environment
FTP / File Transport Protocol
GPRS / General Packet Radio Service
GUI / Graphical User Interface
LDAP / Light Directory Access Protocol
MC / Monitoring Component
NetEnv / Network Environment
PCIM / Policy Core Information Model
QoS / Quality of Service
SIP / Session Initialisation Protocol
SL / Service Layer
SLA / Service Level Agreement
SLO / Service Level Object
SLS / Service Level Specification
URL / Uniform Resource Locator
VPN / Virtual Private Network
WAN / Wide Area Network
EXECUTIVE SUMMARY
The CONTEXT project work involves the design, development and assessment of innovative models and middleware solutions for an efficient provisioning of context-aware services. CONTEXT allows flexible definition, automated provisioning, dynamic customisation and maintenance of services based on context information.
From the technical point of view the CONTEXT solution spans into three domains, namely:
- Active Applications Layer (AAL) domain
- Service Layer (SL) domain
- IP domain
The Service Layer (SL) domain in CONTEXT deals with the modelling of the context aware services and the context information involved, and aims at establishing the required framework for the creation and management of such context aware services. This is possible thanks to the AAL (Active Application Layer), which enhances network technology and uses the appropriate APIs to control the IP domain, allowing the actual delivery and management of the context aware services.
This deliverable contains the specification and design of the CONTEXT Service Layer (SL), which provides a proof of concept for the provisioning and management of context aware service delivery. A detailed overview of the three scenarios considered in the CONTEXT project is also given. This scenarios are proposed as a proof of concept for the CONTEXT architecture. The scenarios are detailed from the context-aware services point of view. Context information involved is identified, and CAS and management policies are described. Scenarios’s testbeds are detailed.
The document starts with a global overview of the Service Layer Architecture, specifying the role of each component and the interactions between them. Then each component’s design and implementation is detailed in the following chapters. The interfaces among and inside them and the syntax and semantics of the information exchanged via those interfaces are fully detailed.
In Chapters 3-7 components related to CAS Creation and Customizationare explained. The means to define context aware services and automatically produce the corresponding service logic and the appropriate information required by the service areis explained. The main components of the CAS creation and customisation are the following:
- Authoring: In charge of produce a coherent and complete service technical definition that will be the basis for the creation and provisioning of the service. Provides a tool to the CAS creation administrator for authoring the service technical definition.
- Customization: In charge of establishing subscription agreements with service consumers for offered CAS, deducing consumer’s customisations emerging from established subscriptions and forwarding customisations to the Code and Policy Generation Engine so as to be implemented.
- Code and Policies Generation Engine: Responsible for producing and disseminating the service code, the customized service code and the service management policies responsible for the management of new services and customisations.
In Chapters 8-9 the components related to Policy-based CAS Management are detailed. The functionality of the different components of the PBMS is detailed and the description of the interfaces between them is specified. The structure of the Policies to be used by the system is defined. The PBMS is formed by the following components:
- Policy Manager: Responsible for receiving and managing policies.
- Decision Making: In charge of policy condition evaluation.
- Policy Repository: Contains all the policies loaded in the system and any other management information needed by the PBSM components in order to develop its functionalities.
- Action Consumers: Responsible for undertaking specific actions following the instructions of the Policy Manager, which reflect the decisions of the Decision Making component.
- Condition Evaluators: Responsible for providing the Policy decision-making component with the necessary information for evaluating policies
In Chapters 10-12 Regarding the Service Management Layer, there are four main functional blocks identified:
- Code Distribution and Maintenance: Controls the distribution of the service code to the code repositories or directly to the service execution points.
- Code Execution Controller: Allows executing active services over the active platform and sending arguments to existing active services.
- Service Invocation Listeners: Service specific components in charge of listening to specific signals implying service execution.
- Service Assurance: Allows diagnosing CAS’s problems and taking care of them during execution time.
In Chapters 13-14 components related to CAS Operation are analysed. This part details the execution environment and the way in which the CASs are executed over the DINA platform, showing the relations between Service Components and the Programmable Network. It also details the Context Information Handling Mechanism, which provides a uniform way to access and disseminate context information, and its main component, the Context Broker.
Chapters 15-17 deal with CONTEXT Scenarios. The three scenarios (Super Mother, Crisis Helper and Moving Campus Economy) are fully detailed, identifying the required context information, the policies needed and the sequence of interactions.
Finally, Chapters 18-19 containcontains the conclusions regarding to the project objectives and some open items for further investigation.
This document is aligned with Deliverable D2.2 “Solution for provisioning and delivery of context aware services” in the sense that the former established the global system architecture of which the service layer is a part. Also this deliverable is related to the IR3.1 “Initial specifications of context-aware service creation and management components” because the former was the starting point on the specification work and this initial specification has been embedded into the current deliverable. Finally, this deliverable is a complement of the deliverable D4.2 “Specification, design and implementation of the necessary components for the enhancement of an active platform for the validation of the project approach” because as D3.2 and D4.2 constitute the complete specification of the CONTEXT project solution.
Copyright 2004 CONTEXT Consortium
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CONTEXT-WP3-D3.2
1introduction
This deliverable presents part of the work carried out in CONTEXT WP3, “Context-aware Service Layer”, concerning the detailed description of the system and its components.
The starting point for the document arepoint for the document is the concepts and the overall system architecture, presented and defined in WP2 (see IR2.1 and D2.2). In this way, D3.2 continues the work started in IR3.1, and aims to map this functional architecture into a computational, ready to implement architecture, where the identified functional components are decomposed into smaller components and mapped into appropriate computational entities.