Border Points: Each cluster has a limited number of defined "border points" – these are the gateways in and out of the cluster.
any value you keep, and unreference (unref) any value you receive.
，推荐阅读WPS官方版本下载获取更多信息
�������ǂނɂ́A�R�����g�̗��p�K���ɓ��ӂ��u�A�C�e�B���f�B�AID�v�����сuITmedia NEWS �A���J�[�f�X�N�}�K�W���v�̓o�^���K�v�ł�
numbers are sometimes later products but not always; some prefixes mean specific