Contactless in-person transaction via high frequency sound

A system comprising:

• a sender device configured to generate an initial audio signal that encodes a package associated with a transaction request;
• and
• a receiver device configured to receive the initial audio signal and decode the initial audio signal to receive a handshake request for establishing a two-way session between the sender device and the receiver device as part of conducting a transaction, wherein the transaction comprises:
• initiating an audio handshake session between the sender device and the receiver device, wherein the audio handshake session is conducted via one or more audio signals including the initial audio signal, wherein the audio handshake session comprises:
• verifying physical proximity between the sender device and the receiver device based at least in part on decibel level of one or more audio signals received by a microphone of the receiver device in the audio handshake session, and
• creating a session key in the audio handshake session;
• establishing a secure electronic session through the audio handshake session;
• conducting a transaction in the secure electronic session using the session key between the sender device and the receiver device.

A device comprising:

• a processor;
• and
• a computer readable medium coupled to the processor, the computer readable medium comprising code, wherein the code, when executed by the processor, cause the processor to perform a process comprising:
• causing a speaker of a sender device to generate an initial audio signal that encodes a package associated with a transaction request, the transaction request comprising a handshake request for establishing a two-way session between the sender device and a receiver device;
• initiating an audio handshake session between the sender device and the receiver device, wherein the audio handshake session is conducted via one or more audio signals including the initial audio signal, wherein the audio handshake session comprises:
• verifying physical proximity between the sender device and the receiver device based at least in part on decibel level of one or more audio signals received by a microphone of the receiver device in the audio handshake session, and
• creating a session key in the audio handshake session;
• establishing a secure electronic session through the audio handshake session;
• conducting a transaction in the secure electronic session using the session key between the sender device and the receiver device.