Mobile agents

The evolution of technology in interconnection solutions, such as networks or the Internet, and the emergence both of wireless sensors networks and distributed systems allowed many communication architectures to appear, being the Client-server architecture the most common. Here, we present a dissertation work about the mobile agents computing paradigm. A middleware and a mobile agent framework have been developed using the JavaScript language that allows the development, execution and the ability to move JavaScript mobile agents through the local network and Internet using Node.js for desktop operating systems and React Native for mobile operating systems, such as Android and iOS. This initiative arose as a way of dealing with problems raised by the considerable amount of existing Java based mobile agents platforms, which force the installation of the Java Virtual Machine on the devices, making complicated its execution in operating systems like macOS, iOS and others operating systems not compatible with Java.

This study proposes a fault tolerant key distribution protocol for mobile agents in network intrusion detection system. It considers a scenario of collaborative mobile agents saddled with a collective task of detecting intrusive packets in data traffic in a Wireless Local Area Network (WLAN). The agents hopping region is confined to the WLAN. However, visiting (external) agents are welcome to the WLAN provided they comply with the internal security policy of the network domain. To minimise computation and memory overheads, an Elliptic Curve Cryptosystem (ECC) and digital signature are used to make the agent collaboration environment and inter agent communication secured. The reason for the choice of ECC is because of its high efficiency and shorter key length compared to RSA while digital signature is to guide against repudiation. Date-constraint key management scheme (Chen et al., 2010) is employed to give validity period to the key. Once the key of an agent expires, such agent will be retracted and terminated. The main contributions of this study are: The design of mechanisms to protect the protocol against single point of security failure and making it fault tolerant using backup agent server in case of the failure of the main agent server and making the appointment of the execution platform dynamic. The backup server, which is configured to have the same resource capability as the main agent server, automatically takes over the responsibilities of the main server at the instance of failure of the main server; the agent server dynamically select the execution platform for the collaborative agents among the host platforms in

The experimental results obtained in the previous section clearly show that client server based network management models takes less time as compare to mobile agent based models for a small size network. As the network grows in size client server based request and response put heavy load on network whereas mobile agents who operate locally at respective agent or node perform much better then client server. Moreover the model deploying database at the M-SNLM side performs even better than the mobile agent model. In client server model the management cost in terms of the data transferred to the Global manager for the whole network is directly proportional to the following factors:

The mobile agents are really small pieces of software that migrate through a network until accomplishing the task given by the user. As such, mobile agents could be a good add in to the client-server paradigm in the area of the Internet of things. Thinking about this scenario consider a house where every single object has some kind of sensor. Currently with the client- server paradigm each and every one of the sensors send information to the server, which results in two consequences, such as the growth of the network traffic and the quantity of data that the server has to process. If this example expands to the level of a university campus or even a city, the number of sensors increases exponentially and so increase the network traffic and the server volume of data to be processed by the server.

Building on this as an infrastructure, we collect information to generate a network map offering information to mobile agents. To achieve this, we implemented a Map Module which consists of several network sensors and a map data structure [9] . The basic concepts of this module are taken from the Network Weather Service [10] . In addition to throughput, latency and other network status information, this module collects and distributes information on application-level services provided by the AH in the domain. By partitioning the network in PMADE Domains, each AH is located within a local domain that reflects its primary area of interest. Each Domain Manager has additional links to a number of selected remote domains. The Map Module cares for precise and up-to-date knowledge (maps) within its local domain and provides a rough, summarized view of the linked remote domains.

• [16] proposes an architecture for fault detection of web services through web services based on passive testing .they proposes an observer (mobile agent) that can be invoked by interested parties when developed and published as a web service. In this model, they have not integrated the concept of Multi-Agent Systems.

The infrastructure less and dynamic nature of MANET demands new set of networking analysis in order to provide diverse application in many different scenarios. So, it is possible that some application demands less overhead as well as fast processing with efficient transmission. This paper, presents the protocol being proposed which utilizes the dual cooperative mobile agents and stationary agents for routing in dynamic networks as MANET. It also provides the transmission capacity factor into the networking as MANET. Each node has its own stationary agents but number of mobile agents in the network depends on the network architecture or the protocol used. Every mobile agent computes the transmission capacity of all the nodes so that Routing Agent System (RAS) can take the decision which routing path is more efficient and reliable also. Here we have presented the analysis of proposed protocol Efficient AB – AODV and evaluation of simulation is considered in future.

An agent’s communicative ability increases the potential advantages of the mobile agent paradigm. This ability enables the development of multi-agent systems. Multi-agent systems differ somewhat from single agent systems. A multi-agent system must include provisions to handle interaction and the current context of other agents in the system. In a multi-agent system, agents or resources can be added or removed from a system as services are initiated or removed. Mobile agents are able to adjust to changing conditions such as network nodes, devices, media services or other agents which may be available or unavailable dynamically. Multi-agent systems can be created that use agent communication to collaborate and work together to provide services, reach a desired outcome or achieve a common execution goal [5, 6].

Mobile agents are computer programs that act autonomously on behalf of a user or its owner and travel through a network of heterogeneous machines. Fault tolerance is important in their itinerary. In this paper, existent methods of fault tolerance in mobile agents are described which they are considered in linear network topology. In the methods three agents are used to fault tolerance by cooperating to each others for detecting and recovering server and agent failure. Three types of agents are: actual agent which performs programs for its owner, witness agent which monitors the actual agent and the witness agent after itself, probe which is sent for recovery the actual agent or the witness agent on the side of the witness agent. Communication mechanism in the methods is message passing between these agents. The methods are considered in linear network. We introduce our witness agent approach for fault tolerance mobile agent systems in Two Dimensional Mesh (2D-Mesh) Network. Indeed Our approach minimizes Witness-Dependency in this network and then represents its algorithm.

The presented mobile healthcare solution for AAL environments improves the lives of elderly people that live alone or in remote locations. It allows continuous assistance and monitoring of bio-signals to identify potential diseases or health risk situations. The eZ430-Chronos watch was used for prevention in an online and offline mode. According to the online analysis, Shimmer sensors are with no doubt an improvement allowing the collection of data within seconds. The use of mobile devices, such as, smartphones or tablets were considered for sending alerts in case of critical situations through data transmitted from various sensors and for mobility purposes. The solution is customizable and only the sensors required are enabled. Also, fall detection and real-time location are deployed. This proposed solution is extremely easy to place on the patient’s body, flexible, and with no harm to his health. System demonstration and performance evaluation shows more precise results and increase the exclusion of possible error results about 2%, and about 0.8%, were obtained by the Texas Instrument watch, and the Shimmer sensors respectively.

Figure 4 shows the state of the scenario, not after 60 seconds, but when the first agent reached the goal. Once again, both the figure and Table 2 show that the number of tiles explored by each agent is directly proportional to its curiosity. How- ever, the explored tiles follow a pattern that gets each agent closer to its goal, which means that the goals are influencing curiosity. This can also be proved by the fact that every agent explored more tiles than during the previous step. Also, as expected, the distance to the goal at the end of each iteration was inversely proportional to the agents’ innate curiosity.

The advent of mobile devices with location-aware and context-aware technologies such as, smartphones, cell phones, and tablets is changing users daily lives. They are capable of putting a pinpoint in our current location on a map or find information about a particular area. The number of applications that use GPS services and features is growing everyday [34]. GPS capabilities are all around us in mobile devices, but location-awareness with iPhone is changing everyone’s life. This device will put into the main stream the location-aware applications [35]. Pinpointing our location on a Google Map, tracking friends, giving a heads-up on what is going on in a given area of interest. The nearest place to eat, list of shopping areas near a user are some of the functionalities that it can offer users. For example, about 70% of young people (18-29 years old) use mobile devices to have access and to get local news for reading. With an aging generation mobile technology will become an important and powerful factor in the news industry [24]. In an urban environment about 48% of the residents use a mobile device to read local news. On the contrary, on a rural area only about 38% have access to local news, as may be seen in Figure 5.

In mobile robot systems, robot control architecture is necessary. Robot control architecture is defined as a mapping of sensory information into actions in the real world, in order to accomplish a certain task. It is a way of integrating different kinds of hardware and software modules. Furthermore, it plays an important role in maintenance tasks and in the addition of new modules.

medium by the addition of chemical modifiers and wetting agents, and antifoam agents); (iv) the mixing and homogeni- zation of the slurry (i.e., the use of stabilizing agents[r]

REST is a new architecture for Web services that is being widely adopted by major technology companies. Most of these companies rely on REST for sharing information and to expose web applications and services. REST architecture is based on client-server communication, where clients initiate requests to servers that process these requests and return the appropriate results. These results are defined as resources and represent the information exposed by the service. RESTful architectures are based on HTTP to communicate over the network. HTTP is the protocol of the Web and it has a set of tools that simplify communications such as Uniform Resource Identifiers, request and response headers and Internet media types. These functionalities allow the mobile client application to use the HTTP methods GET, POST, PUT and DELETE to communicate with the Web service and also to exchange information in several file formats such as XML and JSON.

Implementation is most important stage in the project where the theoretical design of the project is turned into a working system. In this project the implementation techniques of controlling and monitoring LAN through Cell phone. Access and monitoring WLAN Using Mobile application is implemented by using android based platform itself. The system is developed in a way that targeted LAN in Network is controlled by the server machine and then server can controlled all other machine in network. The Mobile Based LAN Monitoring and Control is a tool used to monitor a LAN through a mobile device by the administrator. This application tool is installed on the node which has two independent parts. There are two main application .One is server application which works as a important process on the machine and offer the services to administrator for control and monitor the LAN. Administration has all privileges to monitor LAN in network. Second is the client application which is the secondary process on the machine and controls all the activities of the client. The server application can control through mobile device that are registered on device. Using the mobile the administrator can perform following actions-

Designing complex interfaces for such small viewports 16 can mean a very hard task. However, one of the main features Steve Jobs presented when introduced the iPhone, was the use of natural gestures to manipulate a digital, touch-based, interface. Like zooming an image just by pinching or stretching with two fingers, e.g.. He also referred that it would be distributed without the typical User’s Guide, claiming however it wouldn’t be necessary. What Steve Jobs meant was the interface would be so intuitive that the user would know how to use it, even if he never experienced a touch screen before. It’s true that his viral presentation video from 2007 spread over every media, and was seen by millions of people all over the world, and that helped to know how to use the iPhone and, consequently, upcoming touch-based smartphones. As Hoober and Berkman (2011: 18) observed, most of user interface paradigms from the desktop have been applied to mobile, not making use of gesture interactions, and based just on simply replace mouse pointer to a finger tap. Usually, it’s the operating system itself that makes use of most touch opportunities. But in fact, we are witnessing a steady growth in the use of tangible smartphones capabilities. Likewise, there has been an emerging development focused on user and experience improvement. Almost everyone was fascinated by iPhone’s presentation in 2007 because the interface had a kind of “magic factor” implicit.

What is of great importance for both fields is how well mobile devices and social networks go together. If we were asking ourselves, not so long ago, why would anyone want to up- date their FaceBook status while in a pub, now, it seems the only right way to do this? Twitter and FaceBook, two of the biggest so- cial networks of the moment, are seeing a large percent of their updates being made from mobile devices. Development in phone technology, like the launch of the excellent iPhone 3GS in 2009 caused an exponential

33 We extend our proposed architecture in Figure 11, by adding a centralized data sharing system on top. The central node supports the DFS master component. It stores metadata and has access to the network topology map. The network topology map is responsible for the system’s context awareness. It should keep track of the cluster nodes’ position and battery levels. The retrieval of these metrics on each data-holding node is further explained in chapter 4 (section 4.2). The central node uses a data placement scheme to determine the flow of data in the system. The data placement scheme uses the context awareness information stored in the network topology map. The mobile devices as well as the fixed fog units, should have installed a DFS server instance, to allow for storing data in the system. Fixed fog units that are scarce in resources, can eventually run open-source OSs that make possible installing a DFS server instance to store data on. The mobile devices should also install a DFS client instance, to allow the end users to interact with the data sharing system. When an end user requests a file via the client instance, it is the server instance who retrieves the file (contacts the central node and retrieves the file from another server instance). Once the client instance has received the file, the end user can then access it. The node that received the file, cannot however send this file to other nodes in the system, as it never got stored on the server instance.

existente e de quais as implicações da alteração de cada entidade, existia ainda toda a complexidade de dependências entre projetos (existentes no Visual Studio) que tornariam esta abordagem pouco viável. Um outro motivo que levou a descartar esta abordagem foi o facto de a lógica presente no iZiTraN Web enviar várias vezes informação redundante e desnecessária, tornando-o inviável para a aplicação móvel iZiTraN Mobile, uma vez que esta precisa de fazer comunicações que gastem poucos dados, tendo os mesmos de vir tratados para que não se tenha de fazer muito processamento no dispositivo móvel. Assim, foi desenhado um novo modelo de domínio capaz de suportar toda a lógica do Mobile Fleet Management, tendo sido estruturado de forma a ser o mais estável, flexível, extensível, manutenível e escalável possível, para que no futuro se possa adaptar a eventuais mudanças na lógica de negócio, sem prejuízo da lógica específica. O diagrama geral do modelo de domínio é apresentado na Figura 17.