PRM 1(NO) 2(USER) 3(TELCO) >PRM stands for Performance Response Messages. This is a technique which may be used to send unsolicited status information at regular (one second) intervals over the Facilities Data Link section of an ESF T1.
Use of PRM implies that a network service provider is actively monitoring this PRM information for alarm conditions. If you do not know that this is the case, do not enable PRM.
1(NO) means that PRM functions are disabled. This is the desired selection in most cases.
2(USER) enables PRM and gives access to USER registers as well as TELCO registers.
3(TELCO) enables PRM with access only to TELCO registers, not USER registers.