Patent ID: 6141320
Filing Date: 2000-10-31
Classification: H04J,H04Q

Abstract:
A nested automatic protection switching apparatus for performing automatic protection switching for a communication line going from a first node to a third node via a second node by using a command and a response to be terminated at said second node, comprising:a line identifier comparing circuit for comparing an identifier of a line to be recovered, which is carried in a first command requesting a switching, with an identifier of a line terminated at said second node;a command selector for selecting said first command for transmission to said third node when the result of the comparison from said line identifier comparing circuit indicates a mismatch, or a second command issued to said third node by said second node for transmission to said third node when said result indicates a match; anda response selector for selecting a first response from said third node for transmission to said first node when the result of the comparison from said line identifier comparing circuit indicates a mismatch, or a second response issued to said first node by said second node for transmission to said first node when said result indicates a match.