i have a BTS with electrical uplink port in 100 M full duplex mode and is connected to the GE port of RTN 910 with working mode 100 M full duplex. Cases: 1.both port are in 100 M full duplex but there is an FCS error on the port of RTN with no any alarm in RTN. 2. after chaging the port of RTN in auto negotiation mode there is no FCS error in the port but an alarm of port mode mismatch is coming in RTN. so some one please help to solve the issue. Thank you.