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- Traffic Management in Rural NetworksPublication . Emiliano, Rodrigo; Silva, Fernando; Frazão, Luis Alexandre Lopes; Barroso, João; Pereira, AntónioThe internet is increasingly present in people's lives, being used in diverse tasks, such as checking e-mail up to online gaming and streaming. The so-called "killer applications" are applications that, when not properly identified and prevented, have more impact on the network, making it slow. When these applications are used on networks with limited resources, as happens in rural networks, they cause a large load on the network, making it difficult its use for work purposes. It is important then to recognize and characterize this traffic to take action so that it does not cause network problems. With that in mind, the work presented in this paper describes the research and identification of cost free traffic analysis solutions that can help to overcome such problems. For that, we perform preliminary testing and a performance comparison of those tools, focusing on testing particular types of network traffic. After that, we describe the analysis and subsequent modification of the source code for storing important traffic data for the tests, as well as the test scenarios in laboratory and real-life environments. These tasks are aimed on collecting information that assists in taking action to improve the allocation of network resources to priority traffic.
- Intelligent Distributed Systems for Rural AreasPublication . Frazão, Luis Alexandre Lopes; Meire, Silvana; Pereira, AntónioCommunication technologies have evolved and grown exponentially in recent years. Unfortunately, this growth is not the case in rural areas, where the small population density does not justify the investment made by Internet providers. The creation and development of projects in rural wireless networks are often an effective alternative to traditional Internet providers. However, these projects tend to disappear soon after their implementation due to the cost of managing and solving problems. This paper presents an intelligent distributed system that can help the network administrators in maintenance tasks by applying automatic intelligent actions and decisions, ease the installation of new network devices for end users, automatically update existing devices, and manage network traffic by applying algorithms that will decide based on intelligence. This is achieved by using an intelligent distributed system executed on every device of the network and is capable of making decisions and actions that will help administrators with problem-solving, automatic configuration of devices, proactive bandwidth and network traffic management, and reduce costs in maintaining the network.
- Real-Time Low-Cost Active and Assisted Living for the ElderlyPublication . Almeida, António Henrique; Santos, Ivo; Rodrigues, Joel; Frazão, Luis; Ribeiro, José; Silva, Fernando; Pereira, AntónioThe aging of population in recent years and the increase in life expectancy is raising challenges for finding new ways to guarantee healthy and controlled activities for the elderly. Most of them prefer living in their houses than in a community center, even if they live alone or isolated from their family; at home, their normal routine activities and comfort makes them feel well. In this paper, an Active and Assisted Living (AAL) solution to detect irregular situations in everyday life of the elderly living alone is presented. By using low-cost sensors in an Internet of Things (IoT) architecture we aim to gather data in specific areas of an elderly’s house in order to give the system enough input to detect abnormal behavior. These sensors are non-intrusive to the elderly, do not disturb them, and do not force them to wear a device at all times. These sensors can also send information to edge computing devices that analyze the data in real time using machine learning algorithms and alert family or caretakers when an unusual situation arises. The proposed solution provides a system that monitors the main activities performed by the elderly and creates patterns based on that activity to achieve its results and is scalable in terms of sensors and data input.
- Performance analysis of AES encryption operation modes for IoT devicesPublication . Serra, Luís Filipe Dias; Gonçalves, Pedro Gonçalo Baptista; Frazão, Luís Alexandre Lopes; Antunes, Mário João GonçalvesDaily activities have been increasingly supported by intelligent devices and applications. Smart devices are constantly communicating through the Internet of Things (IoT) networks, either by sending collected data and notifying the actions taken or by receiving instructions for actions to be taken. Most of this communication requires the confidentiality of data through the usage of encryption algorithms, being the Advanced Encryption Standard (AES) algorithm one of the most used. However, how do the operation modes of AES algorithm perform in a resource-constraint device? This paper aims to evaluate the impact on the time to encrypt and decrypt different sized messages in IoT devices when using each one of the five AES modes of operation and the three key sizes defined. The test scenario was implemented using two programming languages, running on a Raspberry Pi device. The results achieved infers that Python was quicker and had a more homogeneous result set than JavaScript implementation in most AES operation modes. These results help to understand the trade-off between IoT devices' security needs and delays in communication caused by the selection of the AES algorithm operation mode.
- An easy-to-use tool to inject DoS and spoofing networking attacksPublication . Almeida, Rafaela; Pacheco, Vasco; Antunes, Mário; Frazão, LuísComputer network attacks are vast and negatively impact the infrastructure and its applicational services. From a cyber offensive and defensive perspective, there are a plethora of tools to craft and inject customized malicious packets in the network and exploit operating systems and application vulnerabilities. Those tools are however hard to operate by practitioners with less knowledge on networking fundamentals and students in the early stage of their studies. This paper proposes an easy-to-use application tool that can produce customized Denial of Service (DoS) and spoofing attacks. It was developed in Python and takes advantage of scapy library to process and inject network packets. A set of experiments was made, and the results obtained show the efficiency and accuracy of the attacks, by impairing the proper functioning of the victim's machines.
- An end-to-end cryptography based real-time chatPublication . Melo, Tiezer; Barros, António; Antunes, Mário; Frazão, LuísConfidentiality protects users' data from digital eavesdroppers when traveling through the Internet. Confidentiality is complex and costly, especially on applications that involve communication and data exchange between multiple users. Cryptography has been the most used medium to achieve confidentiality, being the greatest challenge the sharing of a secret key to a group of people in a safe and effective way. This paper presents a chat application that implements an innovative way of sending messages with end-to-end encryption, in real-time, with a dynamic key store, and without the existence of data persistence. The application stands out from the others by the fact that it innovates the way the keys are shared with multiple users.