Multi-hop wireless network system and authentication method thereof

A multi-hop wireless network system and an authentication method for the same are provided to acquire a share key necessary for hop-by-hop mutual authentication between multi-hop nodes by using a centralized authentication scheme in case of initial mutual authentication between the multi-hop nodes and a multi-hop wireless network and perform distributed authentication between the multi-hop nodes by using the acquired share key, thereby solving a problem that authentication information is scattered and it is difficult to share the authentication information in a distributed authentication scheme and acquiring the authentication information through an authentication server to improve the reliability of initial authentication. A multi-hop wireless network system comprises a BS(Base Station)(11), a first multi-hop node(10-1) and a second multi-hop node(10-2). The first multi-hop node transmits an authentication request message to the second multi-hop node for mutual authentication with the second multi-hop node. The second multi-hop node broadcasts an authentication key request message to the BS and neighboring multi-hop nodes(10-3~10-7) to acquire the authentication key of the first multi-hop node as the authentication request message is received and transmits the authentication key of the first multi-hop node, included in an authentication key response message received from one of the BS or the neighboring multi-hop nodes, to the first multi-hop node. The first multi-hop node and the second multi-hop node generate a new authentication key mutually by refreshing the authentication key of the first multi-hop node.