Support for IPv6 is currently being added to LwIP. An experimental version can be downloaded from git.

The current implementation allows for a dual IPv4/IPv6 stack. IPv6 support is enabled through #define LWIP_IPV6 1 in lwipopts.h.

Although still in development stages, the implementation supports:

• IPv6 layer, parallel to IPv4
• Support in TCP/UDP/RAW pcbs
• Support in Netconn API
• Support in Socket API
• ICMPv6
• Neighbor Discovery
• Multicast Listener Discovery
• Stateless address autoconfiguration
• IPv6 fragmentation and reassembly
• Ethernet IF using ND

IPv6 addresses are specified using the ip6_addr_t define in ip6_addr.h.