: ATM virtual path has recently been paying attention to the effective deployment of IP over ATM. The effective IP service provisioning depends fully on the reliability and optimality of ATM VP layer network because the relationship between IP and ATM VP networks is client and server. In order to guarantee the network survivability of ATM VP layer network and to provide the reliable IP service provisioning, this paper proposes a hierarchical rerouting model in multi-network environment of ATM VP and IP networks. In addition, this paper proposes the alarm correlation and localization model in the hierarchical transport network. And this paper describes the COBRA-based implementation model and its experience.