A system can receive a request for service from the computing device of a requesting user of the network service. The system can select a driver to provide the service for the requesting user, and transmit an invitation to the computing device of the selected driver to facilitate the request for service. The system can receive a dataset from a first device of the computing device of the requesting user or the computing device of the selected driver, the dataset indicating that the first device has detected an ultrasonic signal outputted by a second device of the computing device of the requesting user or the computing device of the selected driver. Based on receiving the dataset, the system can verify that a rendezvous between the requesting user and the selected driver has occurred.