PTP100 messages

I'm getting a significant number of the following errors in the log:

08/14/2017 : 14:17:56 AST : Event: SMSESMSG, MsgType: KARSP, NewState: REGISTERED, Flag 0
08/14/2017 : 14:18:04 AST : Event: SMSESMSG, MsgType: KAREQTO, NewState: REGISTERED, Flag 0

Any idea what they are or what could be causing them?

Thanks