GNU Zebra is a free software (distributed under GNU Generic Public
License) which manages TCP/IP based routing protocols.

It supports BGP-4 protocol as described in RFC1771 (A Border Gateway
Protocol 4) and RIPv1, RIPv2 and OSPFv2.

Zebra uses multithread technology under multithread supported UNIX
kernels.  However it can be run under not-multithread supported
UNIX kernels.

Zebra is intended to be used as a Route Server and a Route Reflector.
Zebra is not a toolkit, it provides full routing power under a new
architecture.

WWW: http://www.zebra.org/