Quagga

[http://www.quagga.net Quagga] is an open source GPL licensed IPv4/IPv6 routing software, originally forked off of the [http://www.zebra.org zebra] project.

The supported routing protocols are

Quagga also supports special BGP Route Reflector and Route Server behavior. With SNMP daemon which supports SMUX protocol, Quagga provides routing protocol MIBs. IPv6 routing is fully supported in RIPng, OSPFv3 and BGP-4+.

IPv6 router advertisement

One can enable IPv6 router and prefix advertisements on a given interface: 

    interface eth0
        ! do not suppress IPv6 router advertisements
        no ipv6 nd suppress-ra
        ! include IPv6 prefix in router advertisements
        ipv6 nd prefix dead:beef::/64

RIPng

RIPng which is an IPv6-enabled RIP protocol is supported according to RFC 2080 in the ripngd daemon. The configuration is simple: 

    ! enable ripng
    router ripng
        ! Set RIPng enabled interface by name
        network sit1
        ! Set RIPng static routing announcemenet on the enabled interface(s)
        route dead:beef::/64
        ! Set an access-list on routing announcements (in or out) to a given interface
        distribute-list local-only out sit1

OSPFv3