Packet fragment forwarding without reassembly

A network device may forward fragments of an IPv4 network packet encapsulated in IPv6 network packets from an IPv6 network to an IPv4 network without reassembling the IPv4 network packet. The network device may receive and buffer the one or more fragments of a fragment flow associated with the IPv4 network packet until it receives a fragment of the fragment flow that includes an indication of the source port of the IPv4 network packet. When the network device receives the fragment that includes the indication of the source port of the IPv4 network packet, the network device may dispatch each fragment of the fragment flow that it has received to the IPv4 network.