Open source Skype?
In an email back to April, Enzo Michelangeli wrote:
I believe that we are finally close to the point where all the bits and pieces for a secure, multiplatform, decentralized, opensource Internet phone + text IM are available, and it would only take some coding effort to put them to work together: - Codec: Speex (www.speex.org) - Portable audio interface layer: Portaudio (www.portaudio.com) - Bulk encryption and authentication: SRTP, now a standard-track protocol (RFC3711) and with an opensource reference implementation available at srtp.sourceforge.net . - Key exchange: authenticated D-H (how to perform the authentication, as I said, should be discussed: biometric is not viable if only the text chat feature is used, and multy-party conferencing calls for suitable extensions to the basic D-H scheme) - Directory and presence: any good P2P content-addressable scheme. Preserving some sort of interoperability with file-sharing applications would solve the bootstrapping problem (hundreds of thousands of nodes are already up and running), but the most popular networks (eMule, Overnet and ReverseConnect) are based on Kademlia, which is a Distributed Hash Table algorithm and therefore doesn't allow sorted access (useful, e.g., to locate the reflector with the largest available bandwidth). I recently discovered a few tree-based distributed algorithms which would allow just that: P-trees: http://techreports.library.cornell.edu:8081/Dienst/UI/1.0/Display/cul.cis/TR2004-1926 SkipGraphs: http://www.cs.yale.edu/homes/shah/html/pubs/skip-graphs.html P-Grid: http://www.p-grid.org
JXTA would be very good for such a purpose. Anyone want to start such a open source project? Instead of waiting Skype to be available on my Solaris 10 laptop, such a project would be a nice fit.
