An announcement method, comprising: 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 a 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 under a situation that the post-switching link state of the first region is consistent with the current link state of the second region, the second region does not need to perform the protection switching; wherein, after the step of the announcement node sending the protection switching request to the second region through a sending port corresponding to the second region, the method further comprises: the second region judging whether the post-switching link state of the first region is consistent with the current link state of the second region and whether a priority of the protection switching request is no lower than a priority of a path failure request of the second region itself; under a situation when determining that the post-switching link state of the first region is inconsistent with the current link state of the second region and the priority of the protection switching request is no lower than the priority of the path failure request of the second region itself, the second region confirming to perform the protection switching. 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 a 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 under a situation that the post-switching link state of the first region is consistent with the current link state of the second region, the second region does not need to perform the protection switching; the second region judging whether the post-switching link state of the first region is consistent with the current link state of the second region and whether a priority of the protection switching request is no lower than a priority of a path failure request of the second region itself; under a situation when determining that the post-switching link state of the first region is inconsistent with the current link state of the second region and the priority of the protection switching request is no lower than the priority of the path failure request of the second region itself, the second region confirming to perform the protection switching.