US Patent 7953943 Epoch-based MUD logging

In one embodiment, a MUD logger receives a notification from another MUD logger maintaining another MUD log for a volume, the notification indicating one or more modifications to be made to a MUD log maintained by the MUD logger receiving the notification, wherein the MUD log includes information for one or more epochs, wherein the information for each of the epochs indicates a set of one or more regions of the volume that have been modified during the corresponding epoch. The MUD logger updates the MUD log associated with the volume, wherein updating the MUD log is performed in response to the notification.