This optional parameter specifies the time period in seconds over which MaxFailedRequests failures cause the target host to be assumed to be failed. The default value is 0. After a host is declared to be failed, no request are forwarded to it until FailureBackoffTime seconds have elapsed. The default value lets the AuthBy to choose a reasonable value which is typically very large. Very short values require a high number of failures to set target host as failed. This value should only be changed in special cases.