交换机工作在。SI模型的（ ）层。

试卷相关题目

SQL Error: select id,body,options from ***_enewstiku where sourceid='29470' and id < 2398770 and id<>'2398770' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29470' and id > 2398770 and id<>'2398770' order by id asc limit 5