Does ACS act like a proxy server to other servers?
A. Yes, ACS receives authentication requests from the network access servers (NASes) and forwards them to other servers. You need to define the other servers. In order to do this, select Network Configuration > AAA Servers on the source. The source server is defined as a TACACS+ or RADIUS NAS on the target. Once those are defined, configure the Distributed System Settings in the source Network Configuration in order to define the proxy parameters.