Ultrasound Proximity Networking on Smart Mobile Devices for IoT Applications
The main aim of this paper is to transfer commands to IoT devices from a Smart Mobile Device by employing proximity networking based on very high-frequency sound waves.
There are a wide variety of existing solutions that attempt to solve the proximity networking problem. The least technical (and unfortunately very common) is for users to simply tell one another the information verbally. This is slow, tedious and insecure due to eavesdroppers. Users may also choose traditional networking approaches such as a cloud-based file sharing apps, email, SMS messages, or similar. These approaches assume that the users have exchanged references (e.g., phone numbers) before hand, and they will expose the information to the service provider. Additionally, encryption is required to protect against eavesdroppers on the network. Other existing proximity networking technologies include near ﬁeld communication (NFC), Bluetooth (BT), and Wi-Fi (ad-hoc mode / Wi-Fi direct). Wi-Fi direct and Bluetooth are relatively long range compared with ultrasound because they penetrate solid walls (including the ﬂoor and ceiling) and can propagate over 100ft. As such, these technologies usually require cumbersome client selection, pairing, special hardware, and encryption protocols to remain secure, which often require user involvement. Regarding Wi-Fi, the spectrum 2.4GHz is becoming increasingly crowded and Wi-Fi networks in the home typically rely on a single consumer-grade network appliance that acts as a switch, router, Wi-Fi access point, NAT device, and ﬁre wall. When all traffic must move through this device it becomes an obvious single point of failure making it an attractive target for malicious actors. For NFC, the range is impractically short and some security problems have been explored recently.
We propose the use of ultrasound as a means of data transmission for proximity networking on commodity, consumer hardware. We are the ﬁrst to closely examine different modulation or demodulation schemes that are inaudible to humans and achieve a high data transfer rate. We proposed to design a library to run well on low-powered devices, and provide a socket-like interface for easy deployment by developers. This helps protect users from various attacks improving the security of our system. We evaluate several aspects of our system including bit error rate, audible noise, and the accuracy of Although Hush is sensitive to sender / receiver orientation, our effective transmission.