PPPD.nl
ppp (Pauls PPP Package) is an open source package which implements the point-to-point protocol (PPP) on Linux and Solaris systems.
It is implemented as single pppd daemon and acts as backend for xl2tpd, pptpd and netctl.
3G, L2TP and PPPoE connections are internally based on PPP protocol and therefore can be managed by ppp.