TNS-12637: Packet received failed (high logon time)

DB version Oracle Database 11.2.0.4

Error in alert.log

Fatal NI connect error 12637, connecting to:
 (LOCAL=NO)

  VERSION INFORMATION:
    TNS for 64-bit Windows: Version 11.2.0.4.0 - Production
    Oracle Bequeath NT Protocol Adapter for 64-bit Windows: Version 11.2.0.4.0 - Production
    Windows NT TCP/IP NT Protocol Adapter for 64-bit Windows: Version 11.2.0.4.0 - Production
  Time: 27-SEP-2014 10:23:08
  Tracing not turned on.
  Tns error struct:
    ns main err code: 12637
    
TNS-12637: Packet received failed
    ns secondary err code: 12532
    nt main err code: 0
    nt secondary err code: 0
    nt OS err code: 0
opiodr aborting process unknown ospid (10820) as a result of ORA-609
Sat Sep 27 10:28:09 2014

Error in $ORACLE_HOME\host12345_nsm\sysman\log\emagent.trc

2014-09-27 09:25:28,546 Thread-7180 ERROR fetchlets.oslinetok: Process stdout = starting...0 
starting 1...
starting 2...
got dbversion..started...
 dbversion is 11dbversion is not 9
2014-09-27 09:25:28,546 Thread-7180 ERROR fetchlets.oslinetok: Process stderr = em_error=Could not connect to dbsnmp/(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=host12345)(Port=1521))(CONNECT_DATA=(SID=nsm)))
            : ORA-12637: Packet received failed (DBD ERROR: OCIServerAttach)

Solution:

Try to update sqlnet.ora file

DEFAULT_SDU_SIZE=2048