An ATM VP-based self-healing ring

This paper proposes an advanced ATM VP-based self-healing ring. This ring system offers better recovery control and path management than the conventional STM-based self-healing ring. This self-healing ring has two main characteristics. First, protection VP´s are established in advance which have the same termination points as the working VP´s regardless of the types of path connection. Recovery is accomplished by connecting the working VP´s to their protection VP´s at nodes adjacent to the failure point. This restores a failed path without internode negotiation. This network, therefore, realizes a simple recovery scheme. Second, recovery is executed in the ATM VP layer. A function to detect and remove the endless looping cells is not needed. The proposed architecture permits the flexibility of VP´s to be applied to path management and recovery. The bandwidth of the protection VP´s can be shared and effective VPI assignment is achieved. The proposed ring network reliably supports various broadband services in a cost-effective manner