In Denial of Service (DoS) attack the network resources are either delayed or refused to be assigned to the requested user [1]. This may occurs due to verity of reasons, could be intentionally or unintentionally. The unintentional case is quite hard to mitigate. In this paper we will refer the former case in context of cooperative networks. In cooperative networks we relay the data via intermediate nodes called relays. The relay selection is mechanism [2] need to be devised with focus on mitigating such attacks. In this paper we will enhance the relay selection mechanism address by [3] to propose the novel relay selection with emphasis on security of Wireless Local Area Networks.