This read-only enumerated value (none(255)/out-of-fax(0)/in-fax(1)) indicates whether this voice port is currently in a fax session, out of fax mode, or the mode doesn't apply. An admin checks this to determine whether the current traffic on the port is being treated as fax rather than ordinary voice. For example, statIfvceFaxMode reporting in-fax(1) tells the admin this voice port has detected and switched into fax-relay handling for the current call.