PROTECTION SWITCHING APPARATUS AND METHOD USING NODE GROUP IN RING STRUCTURE ATM SYSTEM

摘要

PURPOSE: A protection switching apparatus and method using a node group in a ring structure ATM(Asynchronous Transfer Mode) system are provided to make every traffic within a node be switched simultaneously at an instant when protection switching for the node takes place. CONSTITUTION: An NAU(Network ATM ring Unit) of a ring node recognizes a port failure(S110) and informs the opposite NAU paired with a controller controlling the NAU about the failure generation (S112). The controller stores its RNID(Ring Node Identification) in a cell drop register of a traffic filter of the failure-generated NAU(S114). The controller deletes its RNID in a cell drop register of a traffic filter of the opposite NAU(S116). An alarm cell generator of the traffic filter of the NAU which receives information on generation of the failure generates an alarm cell and periodically transmits the generated alarm cell in a forward direction(S118).