纵联保护按通道类型可分为几种?
["\u53ef\u4ee5\u5206\u4e3a\u4ee5\u4e0b\u51e0\u79cd\u7c7b\u578b\uff1a\n1.\u7535\u529b\u7ebf\u8f7d\u6ce2\u7eb5\u8054\u4fdd\u62a4\uff1b\n2.\u5fae\u6ce2\u7eb5\u8054\u4fdd\u62a4\uff1b\n3.\u5149\u7ea4\u7eb5\u8054\u4fdd\u62a4\uff1b\n4.\u5bfc\u5f15\u7ebf\u7eb5\u8054\u4fdd\u62a4\u3002"]