Quagga is a routing software suite, providing implementations of
OSPFv2, OSPFv3, RIP v1 and v2, RIPv3 and BGPv4 for Unix platforms,
including NetBSD, FreeBSD, OpenBSD, Linux, and Solaris.
Quagga is a fork of GNU Zebra which was developed by Kunihiro
Ishiguro. The Quagga tree aims to build a more involved community
around Quagga than the current centralised model of GNU Zebra.

Note that quagga is no longer actively maintained.

Homepage:
https://www.nongnu.org/quagga/
