Cecilia Mascolo
University of Cambridge, Computer Laboratory, Faculty Member
ABSTRACT In recent years there has been an increase in the use of mobile and wireless systems. These networks have communication and co-ordination patterns such as asynchronous and location based communication that are not considered in... more
ABSTRACT In recent years there has been an increase in the use of mobile and wireless systems. These networks have communication and co-ordination patterns such as asynchronous and location based communication that are not considered in fixed, wired systems. Because of this, we need to develop new communication primitives that take these factors into account and thereby maximise the efficiency of mobile and wireless systems.
The UCL group have extensive experience in software systems testing and mobile computing, including realistic mobility models for simulation. Recent work extends this to contextawareness and modelling of ubiquitous computing systems. Prof... more
The UCL group have extensive experience in software systems testing and mobile computing, including realistic mobility models for simulation. Recent work extends this to contextawareness and modelling of ubiquitous computing systems. Prof David S.
The eXtensible Markup Language (XML) was originally defined to represent Web content, but it is increasingly used to define languages, such as XPL, that are used for coding executable algorithms, policies or scripts. XML-related... more
The eXtensible Markup Language (XML) was originally defined to represent Web content, but it is increasingly used to define languages, such as XPL, that are used for coding executable algorithms, policies or scripts. XML-related standards, such as XPath and the Document Object Model, permit the flexible manipulation of fragments of XML code, which enables novel code migration and update paradigms.
ABSTRACT Content-based routing fosters a sharp decoupling between data producers and consumers. Therefore, it is key in highly dynamic scenarios like mobile ad hoc networks (MANETs), where it can provide the building block for... more
ABSTRACT Content-based routing fosters a sharp decoupling between data producers and consumers. Therefore, it is key in highly dynamic scenarios like mobile ad hoc networks (MANETs), where it can provide the building block for higher-level programming abstractions, eg, publish-subscribe and queryadvertise. A few proposals exist for content-based routing on MANETs, addressing the issues concerned with the dynamic network topology.
Abstract The use of the World Wide Web as a communication medium for knowledge engineers and software designers is limited by the lack of tools for writing, sharing, and verifying documents written with design notations. For instance, the... more
Abstract The use of the World Wide Web as a communication medium for knowledge engineers and software designers is limited by the lack of tools for writing, sharing, and verifying documents written with design notations. For instance, the Z language has a rich set of mathematical characters, and requires graphic-rich boxes and schemas for structuring a specification document. It is difficult to integrate Z specifications and text on WWW pages written with HTML, and traditional tools are not suited for the task.
Abstract Many infrastructure-less mobile applications demand the ability to withstand long-lasting network partitions and disconnections. Solutions supporting opportunistic communication have been studied in the context of delay-tolerant... more
Abstract Many infrastructure-less mobile applications demand the ability to withstand long-lasting network partitions and disconnections. Solutions supporting opportunistic communication have been studied in the context of delay-tolerant mobile ad hoc networks. However, they typically assume that the sender determines the intended recipients, using a unicast or multicast address.
Abstract In recent disaster events, social media has proven to be an effective communication tool for affected people. The corpus of generated messages contains valuable information about the situation, needs, and locations of victims. We... more
Abstract In recent disaster events, social media has proven to be an effective communication tool for affected people. The corpus of generated messages contains valuable information about the situation, needs, and locations of victims. We propose an approach to extract significant aspects of user discussions to better inform responders and enable an appropriate response.
Abstract: Epidemics-inspired techniques have received huge attention in recent years from the distributed systems and networking communities. These algorithms and protocols rely on probabilistic message replication and redundancy to... more
Abstract: Epidemics-inspired techniques have received huge attention in recent years from the distributed systems and networking communities. These algorithms and protocols rely on probabilistic message replication and redundancy to ensure reliable communication. Moreover, they have been successfully exploited to support group communication in distributed systems, broadcasting, multicasting and information dissemination in fixed and mobile networks.
Abstract Computing and communication devices pervasively surround our daily life and the presence of embedded systems, including tiny sensors, is increasing exponentially. However, the software and communication mechanisms used to network... more
Abstract Computing and communication devices pervasively surround our daily life and the presence of embedded systems, including tiny sensors, is increasing exponentially. However, the software and communication mechanisms used to network these devices are still the ones that we have been devised 30 years ago for standard computer systems.
Abstract The increasing popularity of portable devices and recent advances in wireless networking technologies facilitate the engineering of new classes of applications, which present challenging problems to designers. Mobile devices face... more
Abstract The increasing popularity of portable devices and recent advances in wireless networking technologies facilitate the engineering of new classes of applications, which present challenging problems to designers. Mobile devices face temporary and unannounced loss of network connectivity when they are moved, they are likely to have scarce resources, and they are required to react to frequent changes in the environment.
Abstract—In this paper we report about our experience in using mobile computing middleware in context of health-care. The dynamicity and variability of context and conditions make this environment very suitable for the use of mobile and... more
Abstract—In this paper we report about our experience in using mobile computing middleware in context of health-care. The dynamicity and variability of context and conditions make this environment very suitable for the use of mobile and wearable computing techniques. The use of small and portable devices can be very beneficial in terms of efficiency and vital support to patients.
Abstract Nowadays companies increasingly aggregate location data from different sources on the Internet to offer location-based services such as estimating current road traffic conditions, and finding the best nightlife locations in a... more
Abstract Nowadays companies increasingly aggregate location data from different sources on the Internet to offer location-based services such as estimating current road traffic conditions, and finding the best nightlife locations in a city. However, these services have also caused outcries over privacy issues. As the volume of location data being aggregated expands, the comfort of sharing one's whereabouts with the public at large will unavoidably decrease.
Abstract Nowadays, the navigation systems available on cars are becoming more and more sophisticated. They greatly improve the experience of drivers and passengers by enabling them to receive map and traffic updates, news feeds,... more
Abstract Nowadays, the navigation systems available on cars are becoming more and more sophisticated. They greatly improve the experience of drivers and passengers by enabling them to receive map and traffic updates, news feeds, advertisements, media files, etc. Unfortunately, the bandwidth available to each vehicle with the current technology is severely limited. There have been many reports on the inability of 3G networks to cope with large size file downloads, especially in dense and mobile settings.
1 INTRODUCTION AND MOTIVATION Mobile code is a recent and complex topic on which application and theory oriented research is now focusing. Java based technologies and mobile agents are having a big influence in the development of new... more
1 INTRODUCTION AND MOTIVATION Mobile code is a recent and complex topic on which application and theory oriented research is now focusing. Java based technologies and mobile agents are having a big influence in the development of new systems and their diffusion is faster than the growth of formal techniques able to deal with mobile code paradigms and characteristics.
Abstract Vehicular networks can be seen as an example of hybrid delay tolerant network where a mixture of infostations and vehicles can be used to geographically route the information messages to the right location. In this paper we... more
Abstract Vehicular networks can be seen as an example of hybrid delay tolerant network where a mixture of infostations and vehicles can be used to geographically route the information messages to the right location. In this paper we present a forwarding protocol which exploits both the opportunistic nature and the inherent characteristics of the vehicular network in terms of mobility patterns and encounters, and the geographical information present in navigator systems of vehicles.
This paper is concerned with an abstract exploration of code mobility constructs designed for use in settings where the level of granularity associated with the mobile units exhibits significant variability. Units of mobility that are... more
This paper is concerned with an abstract exploration of code mobility constructs designed for use in settings where the level of granularity associated with the mobile units exhibits significant variability. Units of mobility that are both finer and coarser grained than the unit of execution are examined. To accomplish this, we take the extreme view that every line of code and every variable declaration are potentially mobile, ie, it may be duplicated or moved from one program context to another on the same host or across the network.
Abstract This paper presents Q-CAD, a resource discovery framework that enables pervasive computing applications to discover and select the resource (s) best satisfying the user needs, taking the current execution context and... more
Abstract This paper presents Q-CAD, a resource discovery framework that enables pervasive computing applications to discover and select the resource (s) best satisfying the user needs, taking the current execution context and quality-of-service (QoS) requirements into account.
ABSTRACT A large number of context-inference applications run on off-the-shelf smart-phones and infer context from the data acquired by means of the sensors embedded in these devices. The use of efficient and effective sampling technique... more
ABSTRACT A large number of context-inference applications run on off-the-shelf smart-phones and infer context from the data acquired by means of the sensors embedded in these devices. The use of efficient and effective sampling technique is of key importance for these applications. Aggressive sampling can ensure a more fine-grained and accurate reconstruction of context information but, at the same time, continuous querying of sensor data might lead to rapid battery depletion.
Abstract In the past few years dynamic and reconfigurable systems have evolved and new strategy and paradigms for the development of applications have been devised. In this thesis we study mobile code based systems focusing on the... more
Abstract In the past few years dynamic and reconfigurable systems have evolved and new strategy and paradigms for the development of applications have been devised. In this thesis we study mobile code based systems focusing on the importance of formalization and investigation of the potential of code mobility.
Abstract Sensor networks are now enabling the monitoring of various environmental phenomena with more accuracy than the previous labour intensive and less technological solutions. This paper is concerned with the application of... more
Abstract Sensor networks are now enabling the monitoring of various environmental phenomena with more accuracy than the previous labour intensive and less technological solutions. This paper is concerned with the application of opportunistic networking techniques to wildlife monitoring, where the sensors are attached to animals moving in their habitat. We present seal-2-seal, a novel protocol for logging of node (ie, animal) contacts in mobile networks and for dissemination of that information to sinks for further analysis.
In this paper we describe and review the course plan and syllabus we use in a course on formal methods in software engineering currently included in the degree in Informatics of the Faculty of Sciences at the University of Bologna. The... more
In this paper we describe and review the course plan and syllabus we use in a course on formal methods in software engineering currently included in the degree in Informatics of the Faculty of Sciences at the University of Bologna. The course matches the theory of formal methods with their practice based on actual tool usage. In fact, the course is centered upon a project whose main goal is to let students learn some formal specification techniques, all supported by specific tools.
Abstract—The underlying fundamental aspect that affects routing and data dissemination in mobile networks is the (communication) contact between nodes. If nodes do not have any contact then any geographical, social or other information a... more
Abstract—The underlying fundamental aspect that affects routing and data dissemination in mobile networks is the (communication) contact between nodes. If nodes do not have any contact then any geographical, social or other information a routing algorithm exploits is lost; thus, the time-evolution of contacts between nodes is crucial to data dissemination.
Abstract Large scale market penetration of electronic devices equipped with Bluetooth technology now gives the ability to share content (such as music or video clips) between members of the public in a decentralised manner. Achieved using... more
Abstract Large scale market penetration of electronic devices equipped with Bluetooth technology now gives the ability to share content (such as music or video clips) between members of the public in a decentralised manner. Achieved using opportunistic connections, formed when they are colocated, in environments where Internet connectivity is expensive or unreliable, such as urban buses, train rides and coffee shops.
Today's Internet architecture and protocols, while perfectly suitable for wellconnected users, may easily experience serious performance degradation and entirely stop working in more challenged networking environments. Such environments... more
Today's Internet architecture and protocols, while perfectly suitable for wellconnected users, may easily experience serious performance degradation and entirely stop working in more challenged networking environments. Such environments are manifold, ranging from mobile users experiencing occasional or frequent disconnections to communication services for remote areas, to vehicular network communication in large areas, sensor networks to habitat or wildlife monitoring, and to space and underwater communications.
The use of the WWW as a communication medium for software engineers is limited by the lack of tools for writing, sharing, and verifying formal notations. For instance, the Z specification language has aa rich set of mathematical... more
The use of the WWW as a communication medium for software engineers is limited by the lack of tools for writing, sharing, and verifying formal notations. For instance, the Z specification language has aa rich set of mathematical characters, and requires graphic-rich boxes and schemas for its specifications. It is difficult to integrate Z specifications and text on WWW pages written with the current versions of HTML, and traditional tools are not suited for the task.
Abstract The characteristics of mobile environments, with the possibility of frequent disconnections and fluctuating bandwidth, have forced a rethink of traditional middleware. In particular, the synchronous communication paradigms often... more
Abstract The characteristics of mobile environments, with the possibility of frequent disconnections and fluctuating bandwidth, have forced a rethink of traditional middleware. In particular, the synchronous communication paradigms often employed in standard middleware do not appear to be particularly suited to ad hoc environments, in which not even the intermittent availability of a backbone network can be assumed.
Abstract Content-based information dissemination has a potential number of applications in vehicular networking, including advertising, traffic and parking notifications and emergency announcements. In this paper we describe a protocol... more
Abstract Content-based information dissemination has a potential number of applications in vehicular networking, including advertising, traffic and parking notifications and emergency announcements. In this paper we describe a protocol for content based information dissemination in hybrid (ie, partially structureless) vehicular networks. The protocol allows content to ldquostickrdquo to areas where vehicles need to receive it.
Next generation embedded systems will be composed of large numbers of heterogeneous devices. These will typically be resource-constrained (such as sensor motes), will use different operating systems, and will be connected through... more
Next generation embedded systems will be composed of large numbers of heterogeneous devices. These will typically be resource-constrained (such as sensor motes), will use different operating systems, and will be connected through different types of network interfaces. Additionally, they may be mobile and/or form ad-hoc networks with their peers, and will need to be adaptive to changing conditions based on context-awareness.
Real technological, social and biological networks evolve over time. Predicting their future topology has applications to epidemiology, targeted marketing, network reliability and routing in ad hoc and peer-to-peer networks. The key... more
Real technological, social and biological networks evolve over time. Predicting their future topology has applications to epidemiology, targeted marketing, network reliability and routing in ad hoc and peer-to-peer networks. The key problem for such applications is usually to identify the nodes that will be in more important positions in the future. Previous researchers had used ad hoc prediction functions.
Abstract—Mobile phones play a pivotal role in supporting ubiquitous and unobtrusive sensing of human activities. However, maintaining a highly accurate record of a user's behavior throughout the day imposes significant energy demands on... more
Abstract—Mobile phones play a pivotal role in supporting ubiquitous and unobtrusive sensing of human activities. However, maintaining a highly accurate record of a user's behavior throughout the day imposes significant energy demands on the phone's battery. In this paper, we present the design, implementation, and evaluation of METIS: an adaptive mobile sensing platform that efficiently supports social sensing applications.
Abstract Z is a declarative, not executable speci cation language. We introduce two methods for formal analysis and testing of behavioral aspects of Z speci cations. We de ne a chemical operational semantics, which supports an abstract... more
Abstract Z is a declarative, not executable speci cation language. We introduce two methods for formal analysis and testing of behavioral aspects of Z speci cations. We de ne a chemical operational semantics, which supports an abstract execution model and some new logic constructs to allow the veri cation of dynamic properties. We then describe a parallel animator of Z speci cations which automatically constructs distributed prototypes in Shared Prolog directly from a re ned speci cation.
With the recent developments in wireless networks (Wavelan, Bluetooth) and the sales of mobile computers of any kind (such as laptopcomputers, Personal Digital Assistants (PDAs), mobile phones etc.) soaring, we are experiencing the... more
With the recent developments in wireless networks (Wavelan, Bluetooth) and the sales of mobile computers of any kind (such as laptopcomputers, Personal Digital Assistants (PDAs), mobile phones etc.) soaring, we are experiencing the availability of increasinglypowerful mobile computing environments that can roam across different types of networks. We have also recently witnessed theacceptance of Logical Mobility (LM) techniques, or the ability to ship part of an application or even a complete process from onehost to another.
Abstract The vast majority of mobile ad hoc networking research makes a very large assumption-that communication can only take place between nodes that are simultaneously accessible within the same connected cloud (ie, that communication... more
Abstract The vast majority of mobile ad hoc networking research makes a very large assumption-that communication can only take place between nodes that are simultaneously accessible within the same connected cloud (ie, that communication is synchronous). In reality, this assumption is likely to be a poor one, particularly for sparsely or irregularly populated environments. We present the context-aware routing (CAR) algorithm.
Abstract Mobile location-based services are thriving, providing an unprecedented opportunity to collect fine grained spatio-temporal data about the places users visit. This multi-dimensional source of data offers new possibilities to... more
Abstract Mobile location-based services are thriving, providing an unprecedented opportunity to collect fine grained spatio-temporal data about the places users visit. This multi-dimensional source of data offers new possibilities to tackle established research problems on human mobility, but it also opens avenues for the development of novel mobile applications and services.
The aim of the ICsE 2001 workshop on XML Technologies and soft w areEngineering (XsE01) is to join the efforts in the complementary areas of softw are engineering and XML [1]. There are tw o different aspects that characterize the... more
The aim of the ICsE 2001 workshop on XML Technologies and soft w areEngineering (XsE01) is to join the efforts in the complementary areas of softw are engineering and XML [1]. There are tw o different aspects that characterize the relationship betw een these areas. The first addresses the use of XML and related technologies for the construction of softw areengineering tools and environments.
Dr. Cecilia Mascolo is a Reader in Mobile Systems in the Computer Laboratory, University of Cambridge. Her research interests are in human mobility modeling. She has published in the areas of mobile computing, mobility and social modeling... more
Dr. Cecilia Mascolo is a Reader in Mobile Systems in the Computer Laboratory, University of Cambridge. Her research interests are in human mobility modeling. She has published in the areas of mobile computing, mobility and social modeling and sensor networking. She is and has been PI and co-PI of EPSRC projects on mobile and sensor networks (SATIN, CREAM, FRESNEL, UBhave, UBiVal and WILDSENSING) and on EPSRC project MOLTEN, investigating time varying complex networks.
Abstract Search algorithms in unstructured P2P networks such as Gnutella use flooding-based techniques for communication and, as a consequence, they produce high message overhead. More dynamic algorithms such as Gnutella's Dynamic Query... more
Abstract Search algorithms in unstructured P2P networks such as Gnutella use flooding-based techniques for communication and, as a consequence, they produce high message overhead. More dynamic algorithms such as Gnutella's Dynamic Query Protocol take into account the user's desired number of results and network topology properties to increase scalability. However, these algorithms only work well for popular files and often fail to locate rare content.
We present a method for analyzing the dynamics of a Z document describing a non-sequential system. First a formal operational semantics based on the chemical metaphor is given to Z. Then, some Unity-like temporal logic constructs are... more
We present a method for analyzing the dynamics of a Z document describing a non-sequential system. First a formal operational semantics based on the chemical metaphor is given to Z. Then, some Unity-like temporal logic constructs are defined on such a formal operational semantics in order to allow the specification and analysis of dynamic and temporal properties of concurrent systems, such as safety and liveness properties.
Abstract Sensor networks have opened new horizons and opportunities for a variety of environmental monitoring, surveillance and healthcare applications. One of the major tasks of sensor networks is the distributed collection and... more
Abstract Sensor networks have opened new horizons and opportunities for a variety of environmental monitoring, surveillance and healthcare applications. One of the major tasks of sensor networks is the distributed collection and processing of sensor readings over extended periods of time. We propose an energy-efficient hierarchical indexing approach for spatial data in sensor networks.
Abstract—The advent of online social media and the growing popularity of sensor-equipped mobile devices have created a vast landscape of location-aware applications and services. This goldmine of data, including temporal and spatial... more
Abstract—The advent of online social media and the growing popularity of sensor-equipped mobile devices have created a vast landscape of location-aware applications and services. This goldmine of data, including temporal and spatial information of unprecedented granularity, can help researchers gain insights into the behavioural patterns of people at a global scale. Here we analyse the textual content of millions of comments published alongside Foursquare user check-ins.
Abstract Due to the inherent nature of their heterogeneity, resource scarcity and dynamism, the provision of middleware for future networked embedded environments is a challenging task. In this paper we present a middleware approach that... more
Abstract Due to the inherent nature of their heterogeneity, resource scarcity and dynamism, the provision of middleware for future networked embedded environments is a challenging task. In this paper we present a middleware approach that addresses these key challenges; we also discuss its application in a realistic networked embedded environment. Our application scenario involves fire management in a road tunnel that is instrumented with networked sensor and actuator devices.
Abstract The analysis of social and technological networks has attracted a lot of attention as social networking applications and mobile sensing devices have given us a wealth of real data. Classic studies looked at analysing static or... more
Abstract The analysis of social and technological networks has attracted a lot of attention as social networking applications and mobile sensing devices have given us a wealth of real data. Classic studies looked at analysing static or aggregated networks, ie, networks that do not change over time or built as the results of aggregation of information over a certain period of time.
Accurate and fine-grained prediction of future user location and geographical profile has interesting and promising applications including targeted content service, advertisement dissemination for mobile users, and recreational social... more
Accurate and fine-grained prediction of future user location and geographical profile has interesting and promising applications including targeted content service, advertisement dissemination for mobile users, and recreational social networking tools for smart-phones. Existing techniques based on linear and probabilistic models are not able to provide accurate prediction of the location patterns from a spatio-temporal perspective, especially for long-term estimation.
Abstract Road congestion results in a huge waste of time and productivity for millions of people. A possible way to deal with this problem is to have transportation authorities distribute traffic information to drivers, which, in turn,... more
Abstract Road congestion results in a huge waste of time and productivity for millions of people. A possible way to deal with this problem is to have transportation authorities distribute traffic information to drivers, which, in turn, can decide (or be aided by a navigator) to route around congested areas. Such traffic information can be gathered by relying on static sensors placed at specific road locations (eg, induction loops and video cameras) or by having single vehicles report their location, speed, and travel time.
Programmable networks offer the ability to customize router behaviour at run time, thus increasing flexibility of network administration. Programmable network routers are configured using domain-specific languages. In this paper, we... more
Programmable networks offer the ability to customize router behaviour at run time, thus increasing flexibility of network administration. Programmable network routers are configured using domain-specific languages. In this paper, we describe our approach to defining the syntax and semantics of such a domain-specific language. The ability to evolve router programs dynamically creates potential for misconfigurations.
Abstract Mobile ad-hoc network are an emerging research field due to the potential range of applications that they support and for the problems they present due to their dynamic nature. Peer-to-peer is an example of a class of... more
Abstract Mobile ad-hoc network are an emerging research field due to the potential range of applications that they support and for the problems they present due to their dynamic nature. Peer-to-peer is an example of a class of applications that have recently been deployed on top of ad-hoc networks. In this paper we propose an approach based on context-awareness to allow peer-to-peer applications to exploit information on the underlying network context to achieve better performance and better group organization.
Abstract A variety of cutting edge applications for mobile phones exploit the availability of phone sensors to accurately infer the user activity and location to offer more effective services. To validate and evaluate these new... more
Abstract A variety of cutting edge applications for mobile phones exploit the availability of phone sensors to accurately infer the user activity and location to offer more effective services. To validate and evaluate these new applications, appropriate and extensive datasets are needed: in particular, large sets of traces of sensor data (accelerometer, GPS, micro-phone, etc.), labelled with corresponding user activities. So far, such traces have only been collected in short-lived, small-scale setups.
The popularity of wireless devices, such as laptop computers, mobile phones, personal digital assistants, smartcards, digital cameras etc. is rapidly increasing. Their computing capabilities are growing quickly, while their size is... more
The popularity of wireless devices, such as laptop computers, mobile phones, personal digital assistants, smartcards, digital cameras etc. is rapidly increasing. Their computing capabilities are growing quickly, while their size is shrinking, allowing many of them to become more and more part of everyday life. These devices can be connected to wireless networks of increasing bandwidth, and software development kits are available that can be used by third parties to develop applications.
Abstract Validation of mobile ad hoc network protocols relies almost exclusively on simulation. The value of the validation is, therefore, highly dependent on how realistic the movement models used in the simulations are. Since there is a... more
Abstract Validation of mobile ad hoc network protocols relies almost exclusively on simulation. The value of the validation is, therefore, highly dependent on how realistic the movement models used in the simulations are. Since there is a very limited number of available real traces in the public domain, synthetic models for movement pattern generation must be used. However, most widely used models are currently very simplistic, their focus being ease of implementation rather than soundness of foundation.
Abstract Recent research suggests that, as in offline scenarios, spatial proximity increases the likelihood that two individuals establish an online social connection, and geographic closeness could therefore influence the formation of... more
Abstract Recent research suggests that, as in offline scenarios, spatial proximity increases the likelihood that two individuals establish an online social connection, and geographic closeness could therefore influence the formation of online communities. In this work we present a study of communities in two online social networks with location-sharing features and analyze their social and spatial properties. We study the places users visit to understand whether communities revolve around places or whether they exist independently.