Secure Connections to Corporate and Portal
LDAP Directories 
The Enterprise Portal supports secure connections using the Secure Sockets Layer (SSL) protocol between the Portal Server and both the corporate and portal LDAP directories. When SSL is used, the data transferred between the two parties (client and server) is encrypted.
For detailed information on configuring LDAP over SSL, see the SAP Enterprise Portal Security Guide on the SAP Service Marketplace. You can find it at service.sap.com/securityguide.