A method implemented by a network element (NE) comprises generating, by a processor, an Internet Protocol version 4 (IPv4) packet comprising an IPv4 header, a plurality of extension headers, and upper layer data, wherein the IPv4 packet indicates a total length of the IPv4 packet and a total length of the plurality of extension headers, indicating, by the processor, a protocol number associated with a first extension header of the plurality of extension headers in a protocol field of the IPv4 header, indicating, by the processor, a protocol used to encode the upper layer data of the IPv4 packet in a last protocol field of a last extension header of the plurality of extension headers, and transmitting, by a transmitter, the IPv4 packet to another NE.