funambol

Funambol provides push email, PIM synchronization, and device management for mobile devices, with all the advantages of open source software.

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How Skype & Co. get round firewalls

Peer-to-peer software applications are a network administrator’s nightmare. In order to be able to exchange packets with their counterpart as directly as possible they use subtle tricks to punch holes in firewalls, which shouldn’t actually be letting in packets from the outside world.

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