Peers are usually run by users that want to play the media. However, one or more trusted peers could be executed by the cluster administrator in order to monitorize the streaming performance and/or minimize the impact of some attacks. Considering that, in general, the trusted peers identities will remain unknown for other peers, the administrator could connect a player to a trusted peer and if the playback is correct, the probability that some malicious peer could be poisoning the media is very low (this could be also done using the monitor peer but remember that the identity of this peer is known and the attacker will avoid to poison the chunks sent to the monitor peer). Another advantage of using monitor peers is that their complaining messages are always true. This permits a eﬀective way of identifying those malicious peers that try to perform a fake complaining attack.