You can use Directory Proxy Server in conjunction with the referral mechanism to achieve the same result. The advantage of using Directory Proxy Server in this regard is that the load and complexity of client applications is reduced. Client applications are only aware of the Directory Proxy Server URL. If the distribution logic is changed, for any reason, this change is transparent to client applications.
The following figure illustrates how the scenario described previously can be simplified with the use of Directory Proxy Server. Client applications always connect to the Proxy Server, which handles the referrals itself.