Author: lee

Build your own Open Secure Telephony Network, some assembly required

The Open Secure Telephony Network is a standard that defines how to configure a VoIP softswitch with the capability to have secure two-way VoIP conversations if both parties are using the same server. The system requires both backend and frontend components, which makes OSTN is a little different than some of the other Guardian apps. Unlike Gibberbot, there are few…

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Cross-Domain calling, or “toll-free long distance VoIP”

In a standard OSTN configuration, the Fully Qualified Domain Name (FQDN) of the server running Freeswitch is a core dependency to operate the service. For example, the domain ostel.me was first configured as a DNS record, a server was bootstrapped with ostel.me as the local hostname and a Freeswitch cookbook was run using the Chef automation system. Because the domain…

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Acrobits Groundwire – OSTN supports iPhone

The Guardian Project develops open source software primarily for the Android platform but we strive for security by design to be a part of all platforms. With OSTN, there are two major components. The the first is the server, which operates as the primary user directory and call switch. The other is the client, which is the program you interact…

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Free SIP Providers with ZRTP support

This post is part of a series on our work researching the Open Secure Telephony Network. After you have CSipSimple installed on your mobile handset, you will need a place to register a SIP username so you can contact others. The fastest way to get started with this is to use one of a handful of free SIP providers. I like the Ekiga…

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