AIoT Driven User-Centered Privacy Protection From Smart Home Assistant Devices

Öz

Smart Home Assistant Devices (SHADs) always listen for wake words such as “Alexa”, “Okay Google,” or “Hey Siri.” As a result, these devices continuously listen even when they are not being used, which can compromise users’ privacy. Existing solutions largely focus on modifying network protocols or enforcing policy changes, but implementation of these approaches depends on authorities and therefore remains inaccessible to users. Other solutions rely on mechanical switches or tactile interfaces, which reduce usability since the main advantage of SHADs lies in their natural audio-based interface. This paper presents an AIoT (Artificial Intelligence and Internet of Things) driven user-centered approach to this privacy issue, named LampGuard, which outperforms existing solutions through two user-centered benefits: (i) its implementation does not depend on authorities, giving full control to the user, and (ii) it uses an audio user interface that aligns with the default interaction model of SHADs. LampGuard incorporates an ultrasonic interference system in the form of a desk lamp that provides localized privacy protection in shared living spaces by confining ultrasonic interference specifically to the home assistant device’s microphone area rather than the entire room. Thus, LampGuard blocks only the SHAD’s microphone and does not interfere with other microphones in the living space, such as cellphone microphones or TV remote microphones. LampGuard uses a separate microphone placed apart from the SHAD to detect wake words like “Hey Google.” Once detected, it briefly disables its interference so the SHAD can wake and operate normally. LampGuard was evaluated using 30 spoken commands at close range (≤20 cm) and extended range (25–50 cm). At close range, the Word Error Rate (WER) increased from 7.64% to 96.56% (p < 0.001), demonstrating effective blocking of the SHAD’s microphone. At longer distances, the WER decreased significantly, confirming that LampGuard does not interfere with other microphones in the room.

Anahtar Kelimeler

• AIoT
• Ultrasonic Jamming
• Physical-Layer Security
• Smart Home Privacy
• MEMS Microphones
• Distance-Dependent Protection
• Voice Assistant Security
• Nonlinear Signal Distortion

Akıllı Ev Asistanı Cihazlarından AIoT Odaklı Kullanıcı Merkezli Gizlilik Koruması

Öz

Akıllı Ev Asistanı Cihazları (SHAD'ler) her zaman "Alexa", "Tamam Google" veya "Hey Siri" gibi uyanma kelimelerini dinler. Sonuç olarak, bu cihazlar kullanılmadıkları zamanlarda bile sürekli dinlerler, bu da kullanıcıların gizliliğini tehlikeye atabilir. Mevcut çözümler büyük ölçüde ağ protokollerini değiştirmeye veya politika değişikliklerini uygulamaya odaklanır, ancak bu yaklaşımların uygulanması yetkililere bağlıdır ve bu nedenle kullanıcılara erişilemez hale gelir. Diğer çözümler mekanik anahtarlar veya dokunsal arayüzlere dayanır, bu da kullanılabilirliği azaltır çünkü SHAD'lerin ana avantajı doğal ses tabanlı arayüzlerinde yatar. Bu makale, bu gizlilik sorununa yönelik AIoT (Yapay Zeka ve Nesnelerin İnterneti) destekli kullanıcı merkezli bir yaklaşım olan LampGuard'ı sunmaktadır. LampGuard, iki kullanıcı merkezli avantajla mevcut çözümlerden daha iyi performans gösterir: (i) uygulanması otoritelere bağlı değildir, kullanıcıya tam kontrol sağlar ve (ii) SHAD'ların varsayılan etkileşim modeliyle uyumlu bir sesli kullanıcı arayüzü kullanır. LampGuard, paylaşılan yaşam alanlarında yerel gizlilik koruması sağlayan bir masa lambası şeklinde bir ultrasonik parazit sistemi içerir ve ultrasonik paraziti tüm odaya değil, özellikle ev asistanı cihazının mikrofon alanına sınırlayarak gizlilik koruması sağlar. Böylece, LampGuard yalnızca SHAD'in mikrofonunu engeller ve cep telefonu mikrofonları veya TV uzaktan kumanda mikrofonları gibi yaşam alanındaki diğer mikrofonlara müdahale etmez. LampGuard, "Hey Google" gibi uyanma kelimelerini tespit etmek için SHAD'dan ayrı bir yere yerleştirilmiş ayrı bir mikrofon kullanır. Tespit edildikten sonra, SHAD'in uyanıp normal şekilde çalışabilmesi için kısa bir süreliğine müdahalesini devre dışı bırakır. LampGuard, yakın mesafede (≤20 cm) ve genişletilmiş mesafede (25–50 cm) 30 sözlü komut kullanılarak değerlendirildi. Yakın mesafede, Kelime Hata Oranı (WER) %7.64'ten %96.56'ya (p < 0.001) yükseldi, bu da SHAD'ın mikrofonunun etkili bir şekilde engellendiğini gösteriyor. Daha uzun mesafelerde, WER önemli ölçüde azaldı ve LampGuard'ın odadaki diğer mikrofonlarla etkileşime girmediğini doğruladı.

Anahtar Kelimeler

• Ultrasonik Karıştırma
• Fiziksel Katman Güvenliği
• Akıllı Ev Gizliliği
• MEMS Mikrofonları
• Mesafeye Bağlı Koruma
• Sesli Asistan Güvenliği
• Doğrusal Olmayan Sinyal Bozulması
• AIoT

Kaynakça

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