Web Services for Remote Portlets (WSRP) standard does not specify additional security mechanism, therefore the same security considerations than for other kinds of Web services may be applied for WSRP.
In WebSphere Portal implementation of WSRP the following security options can be configured:
Secure Socket Layer (SSL) is a protocol that enables secure message communication between servers and clients over the Internet. In a SSL authentication, the server exchanges the server certificate with the client and, optionally, the client exchanges the client certificate with the server. This certificate exchange is for purposes of verify both server and client (optional) identities.
Using SSL ...