An announcement method, apparatus and system are provided. The method includes: an announcement node configuring sending ports of the announcement node in a first region and a second region, wherein, the first region and the second region apply different network protection switching technologies; the announcement node acquiring a protection switching request sent from the first region; and the announcement node sending the protection switching request to the second region through the sending port corresponding to the second region, wherein, a post-switching link state of the first region is contained in the protection switching request, and under a situation that the post-switching link state of the first region is inconsistent with a current link state of the second region, the second region needs to perform protection switching and otherwise does not need to perform the protection switching.