11-08-2012, 02:24 PM
ON EVENT BASED MIDDLEWARE FOR LOCATION AWARE MOBILE APPLICATION
[attachment=31126]
INTRODUCTION
Emerging pervasive and mobile computing applications comprise large numbers of interacting components distributed over large geographical areas. Examples include context aware intelligent transportation systems and city-wide information systems. Middleware to support such applications must deal with the increased complexity that arises from such scale, from the geographical dispersion of components, and from the spontaneously changing connections between components.
Such mobile applications can be characterized as collaborative in the sense that mobile entities use a wireless network to interact with other mobile entities that have come together at some common location. Examples might include tourists visiting the same site or vehicles traveling in the same direction. Having come together in some area, collaborative entities establish connections with other collaborative entities dynamically, temporarily forming a group that has a common goal. The members of such a group may even travel together for a period of time, as in the case of a group of tourists coming together and deciding to participate in a guided tour or a group of vehicles traveling in the same direction forming a convoy to improve driver safety and reduce fuel consumption. Although these collaborative applications may use infrastructure networks, they will often use ad hoc networks since these are immediately deployable in arbitrary environments and support communication without the need for a separate infrastructure.
For pervasive and mobile computing as well as sentient computing, this collaborative style of application allows loosely coupled, highly mobile components to communicate and collaborate in a spontaneous manner anywhere and at any time. In many cases, such applications will be deployed in situations where wireless network infrastructure might be available. For example, museums may deploy wireless local area networks and proposals exist for large-scale deployment of wireless access infrastructure along roads such as the Vehicle Infrastructure Integration initiative in the United States. However, we argue that such
applications cannot rely on the presence of such infrastructure: Tourist attractions such as national parks or archaeological sites are unlikely to have such infrastructure and cost mitigates against ubiquitous wireless infrastructure being deployed on every road. Moreover, there are many collaborative mobile applications that will never be able to avail of such infrastructure such as coordination of Unmanned Aerial Vehicles (UAVs) or autonomous military vehicles deployed in hostile environments.
In principle, event-based communication is well suited to such mobile applications since it naturally accommodates a dynamically changing population of interacting entities and the dynamic reconfiguration of the connections between them. Event-based communication supports asynchronous interconnections between components and is particularly useful where communication relationships among components are dynamically and frequently reconfigured during the lifetimes of the entities. The event-based communication model supports a one-to many or many-to-many communication pattern that allows one or more entities to react to a change in the state of another entity. Event notifications, or simply events, contain the data representing the change to the state of the sending entity. They are propagated from the generating entities, called the producers, to the receiving entities, called the consumers. Events typically have a name and may have a set of typed attributes whose specific values describe the specific change to the producer’s state. A particular consumer may only be interested in a subset of the events produced in the system. Event filters provide a means to control the propagation of events.
Ideally, filters enable a particular consumer to specify the exact set of events in which it is interested. Essentially, a consumer’s event filters are matched against the events received by the middleware and only events for which the matching produces a positive result are subsequently delivered to the consumer application.
Problem Statement
The Event Based communication supports one to many and many to many communications pattern that allows one or more entities to react to change in state. In terms general Entities as Producers and receiving entities as Consumers.
A particular consumer may only be interested in a subset of the events produced in the system. Event filters provide a means to control the propagation of events. Ideally, filters enable a particular consumer to specify the exact set of events in which it is interested.
Existing System
Existing event-based middleware for wireless networks has mainly focused on nomadic applications. These applications are characterized by the fact that mobile entities make use of the wireless network primarily to connect to a fixed network infrastructure but may suffer periods of disconnection while moving between points of connectivity.
Existing Computing devices are becoming more pervasive and the dependence on the information delivered through these devices is increasing. Due to these trends, users expect access to information on multiple devices at various geographic locations at any time, but Users may disconnect when network connectivity is absent or to conserve battery life. Therefore, support for disconnected operation is essential for information dissemination applications that support mobile users.
Existing problem of mobility from the viewpoint of the event-based paradigm and the two separate flavors of mobility identified. While physical mobility is tied to the notion of rebinding a client to different brokers and can be implemented transparently, logical mobility refers to a certain form of location awareness offering a client a fine-grained control over notification delivery in the form of location-dependent filters. But problems concerning the combination of mobility and pub/sub infrastructures remain.
Disadvantages of Existing System
• In existing system the disconnection while entities move from one access point to another, is handled whereas relatively little work has addressed the distinct requirements of collaborative mobile applications, especially those that use ad hoc networks.
• Existing system only identifies but does not classify the factors that affect the performance of Publish/ Subscribe system that supports client mobility.
• Existing system have high cost associated with disconnection operation.
• There is lack in formalization of mobility algorithms for distributed Publish/ Subscribe system.
• No proper middleware to run distributed application on a variety of hardware and operating system.
• Problems concerning the combination of mobility and Pub/ Sub infrastructure not addressed.
Proposed System
For event systems to support collaborative mobile applications, they must enable collocated producers and consumers to be able to discover each other. Producers need to be able to advertise the events they intend to generate independently of their location and consumers must be able to subscribe to events persistently. Consumers must also be able to discover events of interest and to eventually deliver them at the relevant locations.
Event-based middleware to support pervasive and mobile applications in which collaboration between nearby entities is intrinsic must deal with the increased complexity that arises from a potentially large number of interacting entities, From their geographical dispersion we use proximity i.e., location.
Advantages of Proposed System
In this project, we present a number of techniques that can be used by event-based middleware to support collaboration in location-aware mobile applications including :
• location- independent announcement and subscription,
• location-based event filtering, and
• location-dependent delivery of events.
• Inherently distributed event service.
[attachment=31126]
INTRODUCTION
Emerging pervasive and mobile computing applications comprise large numbers of interacting components distributed over large geographical areas. Examples include context aware intelligent transportation systems and city-wide information systems. Middleware to support such applications must deal with the increased complexity that arises from such scale, from the geographical dispersion of components, and from the spontaneously changing connections between components.
Such mobile applications can be characterized as collaborative in the sense that mobile entities use a wireless network to interact with other mobile entities that have come together at some common location. Examples might include tourists visiting the same site or vehicles traveling in the same direction. Having come together in some area, collaborative entities establish connections with other collaborative entities dynamically, temporarily forming a group that has a common goal. The members of such a group may even travel together for a period of time, as in the case of a group of tourists coming together and deciding to participate in a guided tour or a group of vehicles traveling in the same direction forming a convoy to improve driver safety and reduce fuel consumption. Although these collaborative applications may use infrastructure networks, they will often use ad hoc networks since these are immediately deployable in arbitrary environments and support communication without the need for a separate infrastructure.
For pervasive and mobile computing as well as sentient computing, this collaborative style of application allows loosely coupled, highly mobile components to communicate and collaborate in a spontaneous manner anywhere and at any time. In many cases, such applications will be deployed in situations where wireless network infrastructure might be available. For example, museums may deploy wireless local area networks and proposals exist for large-scale deployment of wireless access infrastructure along roads such as the Vehicle Infrastructure Integration initiative in the United States. However, we argue that such
applications cannot rely on the presence of such infrastructure: Tourist attractions such as national parks or archaeological sites are unlikely to have such infrastructure and cost mitigates against ubiquitous wireless infrastructure being deployed on every road. Moreover, there are many collaborative mobile applications that will never be able to avail of such infrastructure such as coordination of Unmanned Aerial Vehicles (UAVs) or autonomous military vehicles deployed in hostile environments.
In principle, event-based communication is well suited to such mobile applications since it naturally accommodates a dynamically changing population of interacting entities and the dynamic reconfiguration of the connections between them. Event-based communication supports asynchronous interconnections between components and is particularly useful where communication relationships among components are dynamically and frequently reconfigured during the lifetimes of the entities. The event-based communication model supports a one-to many or many-to-many communication pattern that allows one or more entities to react to a change in the state of another entity. Event notifications, or simply events, contain the data representing the change to the state of the sending entity. They are propagated from the generating entities, called the producers, to the receiving entities, called the consumers. Events typically have a name and may have a set of typed attributes whose specific values describe the specific change to the producer’s state. A particular consumer may only be interested in a subset of the events produced in the system. Event filters provide a means to control the propagation of events.
Ideally, filters enable a particular consumer to specify the exact set of events in which it is interested. Essentially, a consumer’s event filters are matched against the events received by the middleware and only events for which the matching produces a positive result are subsequently delivered to the consumer application.
Problem Statement
The Event Based communication supports one to many and many to many communications pattern that allows one or more entities to react to change in state. In terms general Entities as Producers and receiving entities as Consumers.
A particular consumer may only be interested in a subset of the events produced in the system. Event filters provide a means to control the propagation of events. Ideally, filters enable a particular consumer to specify the exact set of events in which it is interested.
Existing System
Existing event-based middleware for wireless networks has mainly focused on nomadic applications. These applications are characterized by the fact that mobile entities make use of the wireless network primarily to connect to a fixed network infrastructure but may suffer periods of disconnection while moving between points of connectivity.
Existing Computing devices are becoming more pervasive and the dependence on the information delivered through these devices is increasing. Due to these trends, users expect access to information on multiple devices at various geographic locations at any time, but Users may disconnect when network connectivity is absent or to conserve battery life. Therefore, support for disconnected operation is essential for information dissemination applications that support mobile users.
Existing problem of mobility from the viewpoint of the event-based paradigm and the two separate flavors of mobility identified. While physical mobility is tied to the notion of rebinding a client to different brokers and can be implemented transparently, logical mobility refers to a certain form of location awareness offering a client a fine-grained control over notification delivery in the form of location-dependent filters. But problems concerning the combination of mobility and pub/sub infrastructures remain.
Disadvantages of Existing System
• In existing system the disconnection while entities move from one access point to another, is handled whereas relatively little work has addressed the distinct requirements of collaborative mobile applications, especially those that use ad hoc networks.
• Existing system only identifies but does not classify the factors that affect the performance of Publish/ Subscribe system that supports client mobility.
• Existing system have high cost associated with disconnection operation.
• There is lack in formalization of mobility algorithms for distributed Publish/ Subscribe system.
• No proper middleware to run distributed application on a variety of hardware and operating system.
• Problems concerning the combination of mobility and Pub/ Sub infrastructure not addressed.
Proposed System
For event systems to support collaborative mobile applications, they must enable collocated producers and consumers to be able to discover each other. Producers need to be able to advertise the events they intend to generate independently of their location and consumers must be able to subscribe to events persistently. Consumers must also be able to discover events of interest and to eventually deliver them at the relevant locations.
Event-based middleware to support pervasive and mobile applications in which collaboration between nearby entities is intrinsic must deal with the increased complexity that arises from a potentially large number of interacting entities, From their geographical dispersion we use proximity i.e., location.
Advantages of Proposed System
In this project, we present a number of techniques that can be used by event-based middleware to support collaboration in location-aware mobile applications including :
• location- independent announcement and subscription,
• location-based event filtering, and
• location-dependent delivery of events.
• Inherently distributed event service.