GNU Zebra is free software that manages TCP/IP based routing protocols. It is released as part of the GNU Project, and it is distributed under the GNU General Public License. It supports BGP-4 protocol as described in RFC1771 (A Border Gateway Protocol 4) as well as RIPv1, RIPv2 and OSPFv2. Unlike traditional, monolithic architectures and even the so-called "new modular architectures" that remove the burden of processing routing functions from the cpu and utilize special ASIC chips instead, Zebra software offers true modularity.

Zebra is unique in its design in that it has a process for each protocol.