Gateway and interoperability method of 6lowpan

A gateway and an interoperability method of 6LoWPAN(Low power Wireless Personal Area Networks) are provided to deliver a short 16-bit IPv6 address by performing an IP layer compression in a gateway. In a gateway(40) for an interoperability of a 6LoWPAN(1), a first connecting unit is used for connecting to the 6LoWPAN(1). A second connecting unit is used for connecting to an IPv6 network(2). A compressed IPv6 header expanded by a certain mapping table, is combined with a separated packet, and transmitted to the second connecting unit if an outbound traffic is generated from the 6LoWPAN(1) and transmitted to the IPv6 network(2). If an inbound traffic is generated from the IPv6 network and transmitted to the 6LoWPAN, the compressed IPv6 header is compressed by a certain mapping table, separated from the packet and transmitted to the first connecting unit.