POS目前可以提供多种传输速率的接口，下列不是POS可以提供的接口传输速率的是
A．150Mbit/s
B．622Mbit/s
C．2.5Gbit/s
D．10Gbit/s
参考答案：A
解析： POS是一种高速、先进的广域网连接技术，在路由器上插入一块POS模块，路由器就可以提供POS接口。目前，POS可以提供155Mbit/s、622Mbit/s、2.5Gbit/s和10Gbit/s传输速率的接口。
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| In the doorway of my home, I looked closely at my 23-year-old son, Daniel. In a few hours he would be flying to France to 1 a different life. It was a transitional (过渡的) time in Daniel's life. I wanted to 2 him some words of significance. But nothing came from my lips, and this was not the 3 time I had let such moments pass. When Daniel was five, I took him to the bus stop on his first day of kindergarten. He asked, "What is it going to be like, Dad? Can I do it?" Then he walked 4 the steps of the bus and disappeared inside. The bus drove away and I said nothing. A decade later, a similar 5 played itself out. I drove him to college. As I started to leave, I tried to think of something to say to give him 6 and confidence as he started this new stage of life. Again, words 7 me. Now, as I stood before him, I thought of those 8 opportunities. How many times have I let such moments 9 ? I don't find a quiet moment to tell him what he has 10 to me. Or what he might 11 to face in the years ahead. Maybe I thought it was not necessary to say anything. What does it matter in the course of a lifetime if a father never tells a son what he really thinks of him? 12 as I stood before Daniel, I knew that it did matter. My father and I loved each other. Yet I always 13 never hearing him put his 14 into words. Now I could feel my palms sweat and my throat tighten. Why is it so 15 to tell a son somethin from the heart? My mouth turned dry, and I knew I would be able to get out only a few words clearly. "Daniel," I said, "if I could have picked, I would have picked you." That's all I could say. He hugged me. For a moment, the world 16 , and there were just Daniel and me. He was saying something, but tears misted my eyes, and I couldn't understand what he was saying. All I was 17 of was the stubble (短须) on his chin as his face pressed 18 mine. What I had said to Daniel was 19 . It was nothing. And yet, it was 20 . | ||||
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