OpenGGSN is a Gateway GPRS Support Node (GGSN). It is used by mobile operators as the interface between the Internet and the rest of the mobile network infrastructure. The project also developed an SGSN emulator suitable GPRS core network testing.
OpenGGSN is maintained within the Osmocom (open source mobile communications) project.
Source code repository is at http://cgit.osmocom.org/openggsn/
Mailing list is at https://lists.osmocom.org/mailman/listinfo/osmocom-net-gprs
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