Apparatus, methods and computer programs enable carrying service insertion architecture data plane packets in IPv4 or IPv6 networks by packaging destination addresses using IPv6 mechanisms. For example, a data processing apparatus is configured for receiving, from a service broker, a service label and an Internet Protocol version 6 (IPv6) address of a first service node; receiving an IPv4 packet requesting a service associated with the first service node; creating an IPv6 packet comprising a service label in a Flow Label field of the IPv6 packet, the IPv6 address of the first service node in a destination address field of the IPv6 packet, and the IPv4 packet in a payload field of the IPv6 packet; forwarding the IPv6 packet to the first service node. Approaches allow service insertion architecture support for all-IPv6 traffic including tunneled and non-tunneled techniques for environments in which user applications place data in the flow label field.