Dipanjan Chakraborty - Profile on Academia.edu (original) (raw)

Papers by Dipanjan Chakraborty

Dynamic Service Composition: State-of-the-Art and Research Directions

Service Composition refers to creation of complex e-services with the help of smaller, simpler, e... more Service Composition refers to creation of complex e-services with the help of smaller, simpler, easily executable lightweight e-services or components. In essence, it is much similar to component-based or object-based software design and implementation, but different in ...

Social Network Analysis has emerged as a key paradigm in modern sociology, technology, and inform... more Social Network Analysis has emerged as a key paradigm in modern sociology, technology, and information sciences. The paradigm stems from the view that the attributes of an individual in a network are less important than their ties (relationships) with other individuals in the network. Exploring the nature and strength of these ties can help understand the structure and dynamics of social networks and explain real-world phenomena, ranging from organizational efficiency to the spread of information and disease.

IEEE Internet Computing, 2004

A new smart meeting room system called EasyMeeting explores the use of multiagent systems, Semant... more A new smart meeting room system called EasyMeeting explores the use of multiagent systems, Semantic Web ontologies, reasoning, and declarative policies for security and privacy. Building on an earlier pervasive computing system, EasyMeeting provides relevant services and information to meeting participants based on their situational needs.The system also exploits the context-aware support provided by the Context Broker Architecture (Cobra). Cobra's intelligent broker agent maintains a shared context model for all computing entities in the space and enforces user-defined privacy policies.

Integrating service discovery with routing and session management for ad-hoc networks

Ad Hoc Networks, 2006

In this paper, we propose GSR: a new routing and session management protocol for ad-hoc networks ... more In this paper, we propose GSR: a new routing and session management protocol for ad-hoc networks as an integral part of a service discovery infrastructure. Traditional approaches place routing at a layer below service discovery. While this distinction is appropriate for wired networked services, we argue that in ad-hoc networks this layering is not as meaningful and show that integrating

We describe a new smart meeting room system called EasyMeeting that explores the use of FIPA agen... more We describe a new smart meeting room system called EasyMeeting that explores the use of FIPA agent technologies, Semantic Web ontologies, logic reasoning, and security and privacy policies. Building on a pervasive computing system that we have developed previously, EasyMeeting can provide relevant services and information to meeting participants based on their situational needs. Our system exploits the context-aware support provided by the Context Broker Architecture (CoBrA). Central to CoBrA is an intelligent broker agent that maintains a shared model of context for all computing entities in the space and enforces the privacy policies defined by the users. We also describe the use of CoBrA ontologies, logic reasoning, and privacy protection mechanisms, and evaluate our initial user experience studies.

IEEE Transactions on Mobile Computing, 2006

The paper proposes a novel distributed service discovery protocol for pervasive environments. The... more The paper proposes a novel distributed service discovery protocol for pervasive environments. The protocol is based on the concepts of peer-to-peer caching of service advertisements and group-based intelligent forwarding of service requests. It does not require a service to be registered with a registry or lookup server. Services are described using the Web Ontology Language (OWL). We exploit the semantic class/subClass hierarchy of OWL to describe service groups and use this semantic information to selectively forward service requests. OWL-based service description also enables increased flexibility in service matching. We present simulation results that show that our protocol achieves increased efficiency in discovering services (compared to traditional broadcast-based mechanisms) by efficiently utilizing bandwidth via controlled forwarding of service requests.

Mobile information access involves retrieving information from wired service providers. Often the... more Mobile information access involves retrieving information from wired service providers. Often there are situations where the information is not available from a single service provider but can be obtained by combining information from multiple service providers. It is inefficient and some times impossible for a resource poor mobile device connected over a low bandwidth wireless link to coordinate such activity. In this paper, we describe a middleware to support this mode of access from resource poor mobile devices that take into consideration mobility, resource constraints and service heterogeneity.

The past few years have seen significant work in mobile data management, typically based on the c... more The past few years have seen significant work in mobile data management, typically based on the client/proxy/server model. Mobile/wireless devices are treated as clients that are data consumers only, while data sources are on servers that typically reside on the wired network. With the advent of “pervasive computing” environments an alternative scenario arises where mobile devices gather and exchange data from not just wired sources, but also from their ethereal environment and one another. This is accomplished usingad-hoc connectivity engendered by Bluetooth like systems. In this new scenario, mobile devices become both data consumers and producers. We describe the new data management challenges which this scenario introduces. We describe the design and present an implementation prototype of our framework, MoGATU, which addresses these challenges. An important component of our approach is to treat each device as an autonomous entity with its “goals” and “beliefs”, expressed using a semantically rich language. We have implemented this framework over a combined Bluetooth and Ad-Hoc 802.11 network with clients runningon a variety of mobile devices. We present experimental results validatingour approach and measure system performance.

A Component Based Architecture for Mobile Information Access

Implicit in today's mobile information access scenarios is the assumption that the information re... more Implicit in today's mobile information access scenarios is the assumption that the information required by the mobile host is readily available on the network and that its location is “known” in a static fashion. There is a significant ongoing research on ways to overcome the problems (such as low-bandwidth or mobile networks) existing in delivering available information to mobile systems. We investigate those situations where the information required is not readily available on the network, and where it needs to be obtained by dynamically locating the required data and then possibly initiating a series of computations to obtain the information. This paper presents a layered architecture for addressing this problem generally, and also our initial implementation of this architecture

Service Composition in Ad-hoc Environments

Service Composition refers to the technique of creating complex services with the help of smaller... more Service Composition refers to the technique of creating complex services with the help of smaller, simpler and easily executable lightweight services or components. The spurt of e-services on the web has recently increased the importance of service composition. There has been some research in trying to leverage the wide array of e-services available over the network to be able to

World Wide Web has made information accessible to computer users in various ways not imagined bef... more World Wide Web has made information accessible to computer users in various ways not imagined before. However, there is a huge pool of people, especially in emerging economies, who are still untouched by this revolution and are either unaware of, or are unable or to join this bandwagon. Mobile phones are increasingly empowering the under-privileged to utilize data and services beyond the basic voice communication. However, factors such as high illiteracy rate, cost sensitivity, and user interface issues prevent these users from deriving benefits of available infrastructure and services. To address this, we have developed a novel system -VOISERV that enables ordinary telephone subscribers to create, deploy and offer their own customized voice-driven applications called VoiceSites. It employs a simple voice driven interface which is much more appealing to our target users compared to GUIs. Further, the generated VoiceSites get hosted in the network for low cost of ownership and maintenance, and are integrated with advanced services available in the converged networks of today. This enables a vast majority of population in emerging economies to exploit the benefits of converged services.

Businessfinder: harnessing presence to enable live yellow pages for small, medium and micro mobile businesses

IEEE Communications Magazine, 2007

Applications leveraging network presence in next-generation cellular networks have so far focused... more Applications leveraging network presence in next-generation cellular networks have so far focused on subscription queries, where "presence" information is extracted from specific devices and sent to entities who have subscribed to such presence information. In this article we present BusinessFinder, a service that leverages the underlying cellular presence substrate to provide efficient, on-demand, context-aware matching of customer requests to nomadic micro businesses as well as small and medium businesses having a mobile workforce. Presence, in the context of BusinessFinder, is not simply limited to phone location and device status, but also encompasses dynamic attributes of vendors (both "mobile" and "static"), such as their current availability and workload, expertise and reputation. Besides presenting the architecture and implementation of BusinessFinder with a centralized source of context, we also describe early work on a novel resource-aware query routing algorithm that can efficiently support BusinessFinder query semantics in distributed presence environments of the future

Dreggie: A smart service discovery technique for e-commerce applications

Mobile Networks and Applications, 2005

Service Composition, that is, the development of customized services by discovering, integrating ... more Service Composition, that is, the development of customized services by discovering, integrating and executing existing services has received a lot of attention in the last couple of years with respect to wired-infrastructure or Internet web services. With the advancement in the wireless technology and rapid deployment of mobile devices, we envision that in the near future wirelessly connected mobile devices in a given vicinity will also provide services that can be leveraged in the composition process. This is particularly true of what have been described as “pervasive computing” environments. However, wired-infrastructure based service composition architectures are not designed to consider the various factors like mobility, device heterogeneity, resource variability and reliability in a mobile environment. In this paper, we describe the issues related to service composition in mobile environments and evaluate criteria for judging protocols that enable such composition. We present a distributed architecture and associated protocols for service composition in mobile environments that take into consideration mobility, dynamic changing service topology and device resources. The composition protocols are based on distributed brokerage mechanisms and utilize a distributed service discovery process over ad-hoc network connectivity. We present simulation results of our protocols, and compare them with a centralized service composition protocol traditionally used for wired-infrastructure environments. The results show that our approach clearly outperforms the existing centralized approaches, and that our protocols are able to adapt and better utilize the changing service topology and resources in a mobile environment.

Mobile Networks and Applications, 2004

Directory based service discovery mechanisms are unsuitable for ad-hoc m-commerce environments. W... more Directory based service discovery mechanisms are unsuitable for ad-hoc m-commerce environments. Working towards finding an alternate mechanism, we developed Allia: a peer-to-peer caching based and policy-driven agent-service discovery framework that facilitates cross-platform service discovery in ad-hoc environments. Our approach achieves a high degree of flexibility in adapting itself to changes in ad-hoc environments and is devoid of common problems associated with structured compound formation in mobile commerce environments. Device capabilities and limitations, user preferences regarding device usage, application specifics with respect to mobile commerce are factors that our framework adapts to. We have described our initial implementation of Allia over ThinkPads and iPAQs by extending the LEAP Agent Platform and using Bluetooth as the underlying network protocol. In addition, we evaluated Allia's performance by running simulations of our protocol in Glomosim simulator. We also compared our framework against a structured compound-based architecture.

The World Wide Web (WWW) enabled quick and easy information dissemination and brought about funda... more The World Wide Web (WWW) enabled quick and easy information dissemination and brought about fundamental changes to various aspects of our lives. However, a very large number of people, mostly in developing regions, are still untouched by this revolution. Compared to PCs, the primary access mechanism to WWW, mobile phones have made a phenomenal penetration into this population segment. Low cost of ownership, the simple user interface consisting of a small keyboard, limited menu and voice-based access contribute to the success of mobile phones with the less literate. However, apart from basic voice communication, these people are not being able to exploit the benefits of information and services available to WWW users.

IEEE Transactions on Knowledge and Data Engineering, 2008

With ever growing competition in telecommunications markets, operators have to increasingly rely ... more With ever growing competition in telecommunications markets, operators have to increasingly rely on business intelligence to offer the right incentives to their customers. Existing approaches for telecom business intelligence have almost solely focused on the individual behavior of customers. In this paper, we use the Call Detail Records of a mobile operator to construct Call graphs, that is, graphs induced by people calling each other. We determine the structural properties of these graphs and also introduce the Treasure-Hunt model to describe the shape of mobile call graphs. We also determine how the structure of these call graphs evolve over time. Finally, since Short Messaging Service (SMS) is becoming a preferred mode of communication among many sections of the society we also study the properties of the SMS graph. Our analysis indicates several interesting similarities as well as differences between the SMS graph and the corresponding call graph. We believe that our analysis techniques can allow telecom operators to better understand the social behavior of their customers, and potentially provide major insights for designing effective incentives.

With Telecom market reaching saturation in many geographies and revenues from voice calls decreas... more With Telecom market reaching saturation in many geographies and revenues from voice calls decreasing, Telecom operators are trying to identify new sources of revenue. For this purpose, these operators can take advantage of their core functionalities like Location, Call Control, etc. by exposing them as services to be composed by developers with third party offerings available over the Web. To hide the complexity of underlying Telecom protocols from application developers, the operators are steadily adopting Service Oriented Architecture (SOA) and reference standards like Parlay-X and IMS. However, a number of challenges still remain in rapid utilization of Telecom functionalities for creating new applications -existence of multiple protocols, different classes of developers, and the need to coordinate and manage usage of these functionalities. In this paper, we present SewNet, a framework for creating applications exploiting Telecom functionality exposed over a (converged) IP network. More specifically, SewNet a) provides an abstraction model for encapsulating invocation, coordination and enrichment of the Telecom functionalities, b) renders a service creation environment on top of this model, and c) caters to various different categories of developers. With the help of two use-case scenarios, we demonstrate how SewNet can create services utilizing rich Telecom functionality.