the healing layer or computers 20 22 connected to the network 10 it must be noted that the system healer 28 is also used as a repository for clean copies of all vital files of the monitored computers together with their md5 signatures to speed the process as mentioned the system healer is preferably hosted in a dedicated computer it can also be implemented as either an isolated program through a virtualization mechanism or even as a daemon resident program providing some precautions to be specified later in these two cases the system healer is therefore able to heal not only other systems but to heal itself as well u2014 something very unlikely to be needed anyway as the system healer appears a u201c bare u201d black box with only its system healing ports open unless it is implemented as a daemon on an existing computer without virtualization a possible but not preferred implementation for the system healer a preferred isolation is a virtualization system like z vm on the z series 390 computer line vmware u2122 on hardware that supports it presently the intel and amd 32 bit lines of computers and possibly more another type of isolation though complicated and subject to race conditions could be to have a multiple.