Clustered collaborative architecture brings serious security challenges. One of these collaborative solution is a remote desktop that provides a virtual graphical environment through a network displayed on a thin client. As several thin clients access to the same host, conflicts or non interference problems can raise. Although techniques exist for improving security of a host, few papers present how to secure a remote desktop architecture. This paper1 describes how to provide for this architecture a good level of security with strong authentication, Single Sign On, anomaly and intrusion detection systems. In particular, a correlation system checks that each remote user session have a valid behaviour. Load balancing aspects are discussed through the study of a new algorithm to distribute the server load generated by remote users.