1. A method of electing a leader node in an ad-hoc network comprising: a plurality of nodes in the ad-hoc network transmitting node solicitation (NS) messages and calculating distances between the plurality of nodes using information included in the NS messages transmitted from the plurality of nodes; determining whether the plurality of nodes are candidate leaders by calculating center position values based on the distances calculated by each node; and electing the leader node based on information included in leader election option messages transmitted by each of the candidate leaders.