Asterisk is a hybrid TDM and packet voice PBX (Private Branch eXchange) and IVR platform with ACD functionality. It acts as middleware between the Internet (IAX, SIP, MGCP, Skinny, H.323), telephony channels (like Zaptel, T1, PRI, E1, FXO, FXS, VoIP, VoFR, ISDN, modems, Internet Phone Jack, etc.), and applications (like voice-mail, conferencing, directories, MP3 players, intercoms, etc.). It has many advanced features such as a codec translation API. The base distribution includes several channel backends, as well as applications. However, the beauty of Asterisk is its ability to be extended using its APIs, dynamic module loader, and AGI scripting interface. End users can even write their own applications that run on the system in C or any scripting language of their choice.
Baudline is a time-frequency browser designed for scientific visualization of the spectral domain. Signal analysis is performed by Fourier, correlation, and raster transforms that create colorful spectrograms with vibrant detail. Conduct test and measurement experiments with the built in function generator, or play back audio files with a multitude of effects and filters. The baudline signal analyzer combines fast digital signal processing, versatile high speed displays, and continuous capture tools for hunting down and studying elusive signal characteristics.
capircvd is a voice/fax gateway. It receives fax (G3) and voice-calls using an ISDN-Bus, an AVM ISDN-Card (active or passive) and CAPI20 from isdn4linux, or AVM. It can be used on either P2P (with DDI) or P2M S0-bus. After reception, it can process files (send as mail) using an external handler (included).
El Cid is a caller ID program for Linux. It just sits on your modem waiting for something to happen, parses the input, and displays the caller ID information. All records are logged to a file in csv format so you can easily parse it for logging into a database, viewing on the Web via CGI, etc.
mptc is a Perl script to help you work out whether you're on the cheapest mobile phone network/tariff for your phoning habits. You feed it an itemised phone bill and tariff pricing information, and it will tell you how much that bill would have cost on different tariffs. So far it only supports UK network pricing systems, but could easily be extended and applied in other countries.
PreViking is a telephony daemon written in C. It has been designed with a modular structure that easily allows the addition of different services and the support of different hardware. Current services include a calling card service and a call- back service. PreViking provides an API which includes many functions to do different telephony operations such as call switching, playing/recording messages, and listening/playing DTMF.