"The Diameter protocol includes a capability for message redirection@ controlled by an application-independent ""redirect agent"". In some circumstances@ an operator may wish to redirect messages to an alternate domain without specifying individual hosts. This document specifies an application-specific mechanism by which a Diameter server or proxy (node) can perform such a redirection when the Straightforward-Naming Authority Pointer (S-NAPTR) is not used for dynamic peer discovery. A node performing this new function is referred to as a ""Realm-based Redirect Server"". This memo updates Sections 6.13 and 6.14 of RFC 6733 with respect to the usage of the Redirect-Host-Usage and Redirect-Max-Cache-Time Attribute-Value Pairs (AVPs)."