Cisco ASR 901 threshold logic

This router has inner optical transceiver threshold table. This means when transceiver is inserted in to this device, the device identifies module and chooses optical and electrical parameter alarm thresholds. Router checks optical transceiver vendor part number (40-55 bit) field. Basing on information in this field the appropriate threshold table is chosen. All threshold tables can be seen by issuing command  on Cisco ASR:

show interfaces transceiver threshold table


If third party transceiver has wrong information in this data field, then there is a chance that Cisco ASR will chose wrong threshold table, and though SFP module will work, but alarms will be displayed.