Abstract Assume that a graph models a detection system for a facility with a possible “intruder,” or a multiprocessor network with a possible malfunctioning processor. We consider the problem of placing detectors at a subset of vertices in to determine the location of an intruder if there is any. Many types of detection systems have been defined for different sensor capabilities; in particular, we focus on identifying codes, where each detector can determine whether there is an intruder within its closed neighborhood. In this research we explore a fault‐tolerant variant of identifying codes applicable to real‐world systems. Specifically, error‐detecting identifying codes permit a false‐negative transmission from any single detector. We investigate minimum‐sized error‐detecting identifying codes in several classes of graphs, including cubic graphs and infinite grids, and show that the problem of determining said minimum size in arbitrary graphs is NP‐complete.

While some high school courses like AP Computer Science Principles cover topics such as the internet, they do not typically include hands-on activities on the Internet of Things (IoT) and related concepts like distributed computing. Notable reasons include the complexity of programming distributed systems and the cost of supplying classrooms with the necessary hardware. However, most students already have access to a smartphone or other mobile device, which contains all the necessary hardware to introduce these topics through highly engaging interactive projects. We introduce an open-source mobile app called PhoneIoT that allows students to remotely access their devices and query live sensor data or manipulate the app's customizable interactive display. Unlike other tools such as App Inventor, PhoneIoT is not an app-creation tool; instead, we take a distributed approach, with students' code running on their computers and remotely accessing the phone. This makes it possible to have multiple student programs connect to a single device, or one program connect to multiple devices, creating a truly distributed application. To target broad audiences, PhoneIoT supports simple programming interfaces in both block-based form through NetsBlox (a networking-oriented fork of Snap!) and text form through PyBlox (a Python library). This demonstration will include the basic information needed to install and use PhoneIoT, an interactive walkthrough of a compelling NetsBlox project that students could complete on their first day using PhoneIoT, and finally some interesting projects implemented in Python.

Distributed computing, computer networking, and the Internet of Things are all around us, yet only computer science and engineering majors learn the technologies that enable our modern lives. This paper introduces PhoneIoT, a mobile app that makes it possible to teach some of the basic concepts of distributed computation and networked sensing to novices. PhoneIoT turns mobile phones and tablets into IoT devices and makes it possible to create highly engaging projects through NetsBlox, an open-source block-based programming environment focused on teaching distributed computing at the high school level. PhoneIoT lets NetsBlox programs-running in the browser on the student's computer—access available sensors. Since phones have touchscreens, PhoneIoT also allows building a GUI remotely from NetsBlox, which can be set to trigger custom code written by the student via NetsBlox's message system. The approach enables students to create quite advanced distributed projects, such as turning their phone into a game controller or tracking their exercise on top of an interactive Google Maps background with just a few blocks of code.

Distributed computing, computer networking, cyber-physical systems and the Internet of Things (IoT) are all around us, yet very little of the underlying concepts are being taught in introductory computer science courses in K12. Teaching IoT is especially problematic since it requires hardware with its own cost and maintenance requirements that many under-resourced schools cannot afford. However, smartphones are commonplace networked devices that boast a wide range of sensors. With the right approach, they can be used to introduce many advanced computing concepts even to novices. We have created a mobile app, PhoneIoT, which makes all available sensors accessible to the user's computer through NetsBlox, a block-based educational programming environment specializing in networking and distributed computing. Accessing PhoneIoT uses the same simple networking primitives as other NetsBlox services, so no additional knowledge is required. PhoneIoT makes it possible to collect sensor data, build a custom graphical interface on the device and receive corresponding events, all without leaving your browser running NetsBlox. This demonstration will showcase a few simple projects such as an exercise tracking app and how to turn your phone into a game controller.

While educational robotics and makerspaces are useful to modern STEM education, they introduce both physical and economic barriers to entry. By creating a simulated, networked environment, we can facilitate instruction on cyber-physical systems and related topics while reducing cost and complexity. The virtual environment created is connected to a block-based programming language, NetsBlox, to allow students to engage with the curriculum regardless of programming experience. The networked simulation and collaborative programming environment combine to become especially effective for distance learning. This demonstration showcases example scenarios providing students with a simple interface to interact with a simplified sensor network in a small area of a smart city and solve robot challenges.

Many block-based programming environments have proven to be effective at engaging novices in learning programming. However, most restrict access to the outside world, limiting learners to commands and computing resources built in to the environment. Some allow learners to drag and drop files, connect to sensors and robots locally or issue HTTP requests. But in a world where most of the applications in our daily lives are distributed (i.e., their functionality depends on communicating with other programs or accessing resources and data on the internet), the lack of support for beginners to envision and create such distributed programs is a lost opportunity. This paper argues that it is not only feasible, but crucial, to create environments with simple yet powerful abstractions that open up distributed computing and other widely used but advanced computing concepts including networking, the Internet of Things, and cybersecurity to novices. By thus removing the walls around our environments, we can expand opportunities for learning considerably: programs can access a wealth of online data and web services, and communicate with other projects. Moreover, these changes can enable young learners to collaborate with each other during program construction whether they share their physical location or study remotely. Importantly, providing access to the wider world will also help counter widespread student perceptions that block-based environments are mere toys, and show that they are capable of creating compelling applications. The paper presents NetsBlox, a programming environment that supports these ideas and shows that tools can be designed to democratize access to powerful ideas in computing.