CAMP-UP System Interaction

1) Space Manager identifies that a device has entered the space,

Space sends context information, such as a label for the space’s location and a description of the space’s current activity, to the device.

At the same time, the space also asks the device for the set of functionalities that it is exposing to the space, given the context information.

A device is said to expose a functionality (e.g., ringer volume, vibration) if it allows the Space Manager to have control over that particular functionality (e.g., allows the space to set the ringer volume to certain level)

2) Phone Manager passes the context information it received from the space to the Context Aggregator

3) Context Aggregator update the context database, in which all the context Information is stored

4) Context Interpreter derive higher-level context information using the passed context information,

5) Context Interpreter store the derived context information in the context database

6) Phone Manager gets the derived context information from the database.

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CAMP-UP System Interaction

7) Phone Manager uses the derived context information as parameter in a query to retrieve the set of exposed functionalities the functionality database

8) the response is obtained to Phone Manager

09) Phone Manager send exposed functionalities back to the Space Manager

10) Space Manager determines the set of functionalities that need to be set for the current space’s activity, by consulting the space policy

11) Policy Controller tries to match the device’s exposed functionalities with space required functionalities, based on the space’s current policy DB

12) Policy Controller updates the Space Manager with the required functionalities

13) Space Manager sends a message to the phone asking to set functionalities to certain modes

14) phone manager sets the phone to certain modes, based on the space requirements

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On the Space SideTwo basic types of context information

• Location - current location of the Space Manager (e.g., home, car, room)

• Activity - represents the current actual activity within the space.

• Derived from an activity schedule

• the space has its own context aggregator and context interpreter, as well as sensors to determine the current activity occurring within the space.

Space Manager

• discovering new devices that enter the space and leave the space

• When the device enters the space, the Space Manager will initiate a new connection with the client and send the current context information

• ask for the set of exposed functionalities from any device in the space area and connected to the Space Manager

• Space control over device functionality

• for compliance reasons to follow the space policy

– In the hospital or air plane silent mode

• for convenience of the user

– Watching a movie in a cinema silent mode

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On the Space Side

Policy controller

• perform a comparison to match the set of exposed functionalities sent by the device with the space-required functionality based on the space’s current policy

Policy database

• stores the space policy for each particular type of space activity.

• space policy identifies the required settings on the device functionalities based on the space’s current activity.

Ex) Rule such as “when the space’s activity context is lecture, every mobile phone is required to be silent and set to vibration off mode.”

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On the Client Side

Five components for supporting context awareness and user preferences

1. Phone Manager

2. Context Aggregator

3. Context Information

4. Context Interpreter

5. Functionality Database

Phone Manager : main software component to control the mobile phone interaction with the Space Manager

Four tasks of the Phone Manager

1. Establish and maintain the connection with the Space Manager

2. Update the context aggregator : new context information received from the space

3. Send the set of functionalities that are exposed from the phone to the space

4. Update the phone mode

when the Space Manager sends a message requiring functionalities to be set to a certain mode based on the space policy

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On the Client Side

Context Aggregator – gather the context information & record it in the Context DB

• Context information from the Space Manager , and other sources as well, such as the device’s calendar that resides in the phone itself or other sensors attached to the phone

• For new context information or a context change, asks the context interpreter to derive new high-level contexts

Information stored in the Context Database

• Low level context information : location, space’s current activity

Ex) “bathroom, hotel, and restaurant”, “lecture, meeting and conference, dinner”

• Higher level, derived using the inference engine.(=Context Interpreter)

Ex) “lecture at Sogang University” and “meeting with supervisor,”

• Updated whenever the context aggregator receives new context information.

Ex) 회의실 입장(location), 이사회 중(activity),…

Functionality database

• Store data of associates’ phone functionalities for each level of exposure

• Store rules that map situations (or derived context in this case) to levels of exposure.

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Discussions for control

The first is the space control of device functionality for compliance reasons;

• the device has an obligation to follow the space’s policy

• There are a number of ways to enforce compliance by the user’s device, such as asking the user to sign an agreement before utilizing services or coming into particular spaces. For compliance, there has to be a mechanism to ensure that the device obeys the space requirements

The second perspective is the space control of device functionality for the convenience of the user

• the space automatically sets the phone to particular modes to avoid the users having to do this manually

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Context-aware Mobile Software Agents For

Interaction with WEB Services in Mobile Environments

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CALMA Agents

CALMA : Context-Aware Lightweight Mobile BDI Agents

• Intelligent S/W agents running on mobile agents , which are context aware for interacting with WEB services

• Implementation issues & Evaluation of CALMA

Compare to previous weeks (=Context-Aware mobile services),

• We attempt a deeper exploration of the notion of the agents for functionality and intelligent behavior.

We think the AGENTS, not the Services, as being context aware.

• We consider the context in which software agents find themselves

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Agents : Mobile and Intelligent

What is an agent?

• Interact with users, applications, and agents

• collaborate with the user

Situated in their environment and react/respond to stimuli from their environment

Proactive (상황에 앞서서 주도, 사전 대책)

Autonomous (자동적)

Communicative (다른 것들과 연계)

Adaptive (상황에 따른 유연하게 적응/ 조정)

Software agents help with repetitive tasks

Applications,

Personal assistant (mail filter, scheduling)

Information agent (tactical picture agent)

E-commerce agent (stock trader, bidder)

Recommendation agent (Firefly, Amazon.com)

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What is a mobile agent?

Mobile Agents and the Future of the Internet, 1999, David Kotz

Mobile agent: programs that

• migrates from machine to machine

• in a heterogeneous network

• at times of its own choosing

Definition : In a broad sense, an agent is any program that acts on behalf of a (human) user. A mobile agent then is a program which represents a user in a computer network, and is capable of migrating autonomously from node to node, to performs some computation on behalf of the user.

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Machine A Machine B

Searchengine

What is a mobile agent?

Evolution

Mobile Agents are a distributed computing paradigm

End point in the incremental evolution of mobile abstractions such as mobile code, mobile objects, mobile processes.

Mobile Code – transfers code

Mobile Object – transfers code + data

Mobile Process – transfers

code + data + thread state

Mobile Agent – transfers

code + data + thread + authority of its owner

Applet – Downloaded from server to client

Servlet – Uploaded from client to server

Mobile Agents – Detached from client, can have multiple hops

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Advantages of the Mobile Agent Paradigm

Advantages of the Mobile Agent

Reduce bandwidth consumption and network loads

Allow dynamic deployment of application components to arbitrary network sites

Encapsulate protocols

Execute asynchronously and autonomously

Can adapt by moving

Run on heterogeneous platforms

Most distributed applications fit naturally into the mobile agent model

Intuitively suitable for mobile users and disconnected operations

Mobile agents combine the strengths of techniques such as RPC, java applets etc. into a single, convenient framework

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Context -Awareness : key attribute for mobile agents

Context awareness is a key attribute for mobile agents in ubiquitous environments

• perform tasks such as migrate when resources are running low

• migrate when a connection is available

• avoid embarking on a task that requires continuous connectivity

• a computational overhead needs to be taken into consideration of using context awareness

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MyCampus : An Agent-based semantic web environment for context-aware mobile services : CMU

• Revolves around a growing collection of customizable agents capable of (semi-) automatically discovering and accessing Intranet and Internet services

• planning an evening out, organizing a study group, looking for a place where to eat, or filtering incoming messages

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MyCampus

User access personalized, context-aware agents from PDA over the campus’s wireless LAN

Context information : location on campus by WiFi, Calendar, preferences, friends& classmates, weather

Message filtering agents, Message routing agents, Context-sensitive reminder agents,…Ex) Restaurant Concierge : MyCampus Agent.

It returns recommendations on where to have eat based on the user’s current context and preferences

Plans : Developing & Executing plans by agentsbased on the user’s current context & information(semi-)automatic discovery & access of Web SVC’s

Shared Ontologies : Describing contextual attributes, user preferences and web services, Making easily accommodate new task-specific agents and new Web services.

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MyCampus

Each entity has its own set of policies & policy evaluation agents

Personal Resource Ontology:Automatic identification of

available sources of contextual information

CALMA ArchitectureBDI agent Model

BDI agent model :

• A software model developed for programming intelligent agents, used in complex multiagent systems

• draws inspiration from the philosophy of human mentalistic concepts of beliefs, desires, and intentions

• From the programming perspective, two key concepts in the BDI model are 1. goals

2. plans : XML base language

the procedure for accomplishing goals)

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Wooldridge, 2002, An introduction to multiagent systems, JOhnWiley & Sons

BDI agent ModelBeliefs: Informational state of the agent, in other words its beliefs about the world

(including itself and other agents).

• also include inference rules, allowing forward chaining to lead to new beliefs

• Belief set: Beliefs are stored in database called a belief base or a belief set .

Desires: The motivational state of the agent.

• Situations that the agent would like to accomplish or bring about.

Ex) find the best price, go to the party or become rich.

• Goals: A goal is a desire that has been adopted for active pursuit by the agent.

Ex) one should not have concurrent goals to go to a party and to stay at home -even though they could both be desirable.

Intentions: Desires to which the agent has to some extent committed.

• In implemented systems, he agent has begun executing a plan.

• Plans: Plans are sequences of actions (recipes or knowledge areas)

Events: Triggers for reactive activity by the agent.

• An event may update beliefs, trigger plans or modify goals.

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Context-aware Addressing and Communication for People, Things, and Software

Agents

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Context Aware Communication

Use of context for enhancing communication among Entities,

• Including People, Things, Software Agents

• Gather context information about entities, which is used to enhance or regulate communication-related actions

• Sensing and Thinking subsystems can be decoupled, built separately.

CAMP-UP case (studied before)

• Show how a device can be adapted via context information

• The device is a communication device though the idea is applicable to other devices, including the coffee maker

Use of context for communication

• People to people

• People to objects (devices, appliances, everyday objects with embedded computers)

• People to software agents

• Software agent to software agent

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