从硬件构成来看，通信网由终端节点、交换节点、业务节点和（ ）构成。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='28964' and id < 2357906 and id<>'2357906' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='28964' and id > 2357906 and id<>'2357906' order by id asc limit 5