ithin the recov- ery process. The subphases and the associated elapsed times are illustrated in Table 8.8. Telecommunication Networks TABLE 8.8 Definition of the Failure Management Phases and the Corresponding Times Overall restoration Restoration (any type) Total recovery time for restoration scheme type recovery time j (j = 1, 2,3) TPROT Overall protection Protection (any type) Total recovery time for protection schemes recovery time Time with packet losses Any technique Time in which there are packet losses Recovery time before Any technique Time required before starting the switchover of switchover traffic Delay associated to the Any technique Delay between the last packet from the working recovery time path and the last packet of the back-up path Fault detection time Any technique Time to detect the fault Hold-off time Multilayer or multi- Time to allow the lower layers to recover the strategy survivability failure Fault notification time Any technique Time to inform to the node responsible of the switchover that a failure has occurred Backup routing time Restoration type 1 Time for new backup creation and routing Backup signaling time Restoration type 1 Time required to activate the backup path and 2 Backup assigning time Restorations types 2 Time for pre-provisioned backup assignment to and 3 the failed path Backup signaling time Restoration type 3 Time for advertisement of the pre-provisioned backup assignment to the failed path Backup activation Any technique before the switchover Switch over time Any technique Time to switch the traffic from a working path to the backup path Recovery completion Any technique Time to complete the fault recovery, i.e., the time it takes the first packet to arrive from the backup path to the merging node TRDET Initial path recovery Any technique Time to detect that the working path has been detection time repaired TRNOT Initial path recovery Any technique Time to notify about the working path recovery notification time Switchback time Any technique Time taken to switch the