Pre-configured routing is a routing scheme that except primary route operator configures one or multiple routes which will be used as recovery route when the primary route fails for a service previously. This document improves this traditional routing shceme, and PCE (Paht Computation Element) is applied for pre-configured routing. Furthermore, this document also presents a detailed set of PCC-PCE (Path Computation Client) communication protocol requirements and defines PCEP (Path Computation Element Communication Protocol) extensions for PCEP.