腹痛多为活动后绞痛的是
A. 肠梗阻
B. 急性阑尾炎
C. 腹膜炎
D. 肾输尿管结石
E. 急性胃肠炎
In the function model of access network defined in ITU-T G.982, there are five successive building blocks in the user data plane, which are______________, ______________, ______________, ______________, ________________.
TreetopologyisusedinPONsystem,whichiscomprisedof______________,______________,______________.
In SDN, there are two planes: ______________plane is responsible for processing and delivery of packets with local forwarding state;______________plane is responsible for computing the state in routers (forwarding state).