Encrypt your SQL*Net traffic

ssh -X oracle@server_name

‣ Run the command NETMGR from a Unix prompt (make sure you're Oracle and have environment variables set)
‣ PROFILE
‣ NETWORK SECURITY 
‣ ENCRYPTION tab
‣ REQUIRED menu item on the «Encryption Type» drop down
‣ Type a seed value in the «Encryption Seed» text box, up to 256 characters
‣ Choose an Encryption Method AES256
‣ File —> Save Network Configuration

‣ vi /u01/oracle/database/11.2/network/admin/sqlnet.ora