Security issues of typical Voice over Internet Protocol (VoIP) applications are studied in this paper; in particular. the open source Linphone application is being used as a case study. An experimental analysis indicates that protecting signalling data with the TLS protocol. which unfortunately is not always the default option. https://www.markbroyard.com/hot-save-turbo-air-m3f24-1-n-29-wide-m3-series-reach-in-freezer-featuring-one-solid-door-energy-star-on-sale-top-super/