Many people are unaware that the apps on their smartphones share information about where they go. App permissions can change with updates, and the settings that control location sharing might be hidden or masked. 사람찾기흥신소
Disparities in mobile phone use, digital literacy, and tech uptake could also exclude vulnerable or marginalized populations from public health responses that unduly rely on mobile location tracking.
Bluetooth Proximity Tracing
In the face of a global pandemic, governments and software developers are working together to make it easier for people to stay safe and get back to work. One such tool is digital proximity tracing (DPT), which uses smartphones to monitor whether people have kept the recommended six feet or two meters distance between themselves and other people to minimize the risk of Covid-19 transmission.
This technology relies on Bluetooth, a wireless signal that can communicate data without using much of the phone’s power. When phones come within range of each other, the Bluetooth signals can detect a strength of signal called RSSI, which varies depending on how close the phones are.
Apps developed for the purpose can use this data to identify people who may have been in close contact. But the system could be hampered by privacy concerns and people’s unwillingness to share Covid-19 information with apps. It also needs a safeguard to ensure that only a person with an official diagnosis can activate the feature.
GPS Proximity Tracing
In addition to the proximity and duration thresholds that are often discussed, privacy-preserving proximity tracing systems must consider what parameters best reflect the desired proximity measurement with regional variations. In particular, what is the distribution of false positives and false negatives for different device models/manufacturers/platforms under various settings?
Additionally, proximity tracing apps must be easy to use by the public, including those who may not have regular access to smartphones or know how to install and use them. A low adoption rate could render the apps less effective as well as erode trust in their privacy and data-sharing practices. Moreover, apps must be able to exchange data between states and countries, potentially a challenge given recent scams that attempt to steal users’ location information for malicious purposes.
Wi-Fi Proximity Tracing
Proximity tracking systems use Wi-Fi to transmit proximity information to tracing apps. This approach avoids the need for continuous smartphone connectivity, reducing power consumption and data transfer requirements. It also allows for more robust, richer discovery information exchange and reduces the need for immediate service revenue generation.
For example, sensors built into smartphones can broadcast radio waves carrying a unique identifier, which is automatically recognised by other smartphones that recognise this payload. The identifying information can then be used to register close contacts who would receive risk notifications if a COVID-19-positive case in the contact list was detected by a testing or trace service.
However, this requires a lot of radio energy to operate non-stop on battery-powered devices and may expose privacy risks. The identifiers could be revealed by adversaries using more powerful sensors to capture and intercept the ephemeral radio signals, or by linking the tracing data with other traces (e.g. from social media). In order to reduce these risks, tracing apps can employ secret sharing schemes that split up ephemeral identifiers in parts and broadcast them over time.
Email Proximity Tracing
The key functionality of DPT is to identify infected individuals and notify their contacts (the people they may have transmitted the disease to). This involves identifying infected cases, interviewing them and their contacts about recent interactions, asking for testing or quarantine if necessary, and coordinating containment measures. It is time consuming and relies on people being available for interviews, remembering their interactions with infected individuals, and being acquainted with them. Apps that support contact tracing could accelerate this process.
DPT apps typically use a privacy-preserving architecture based on the DP-3T blueprint and therefore do not send proximity data to centralized servers. Instead, these systems detect proximity encounters by downloading pseudonymous, random identifiers from an infected person’s device and then scanning their own devices for those identifiers. If a device adopter has a matched set of those identifiers, the app will notify them of their potential exposure risks to COVID-19. These notifications are usually followed by information lines or options to get tested and to voluntarily enter quarantine in some countries.