对于复杂的计算机网络协议，最好的组织方式是层次结构模型。一般将计算机网络层次模型和各层协议的集合定义为______。
参考答案：网络体系结构
解析： 网络协议是计算机网络通信的要素之一，一个功能完备的计算机网络需要制定一整套复杂的协议集。而对于复杂的计算机网络协议，最好的组织方式是层次结构模型。计算机网络层次模型和各层协议的集合定义一般被定义为网络体系结构。
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| One misfortune led to another, and that's how Alexandra came to live with my family. Within days, she packed and 1 her family behind to live with us. She walked into our house as a 2 , nervous and uncomfortable, smiling 3 but finally feeling safe. At first, she spent most of her time in her room, only showing her face at dinner time. But each night she became more a 4 of our family. Soon enough, I met the real Alexandra, a 5 girl who jumped at unexpected noises, had an unforgettable laugh, and was somewhat misunderstood. She 6 right in with the weird mix of my family, bringing her own sparkle (活力) to our 7 . After a while, I became very 8 to her. We painted each other's nails and texted inside jokes only a few feet away from 9 . She would even tease me like an older sister. I admired her because she opened up to us 10 she had suffered so much. Through it all she was still the 11 person she had always been. She was not with us very long; she had dreams yet to realize. Her ambition was 12 , and she decided a local college was 13 she would study English and Secondary Education. Because of my family she was able to follow through with her 14 . Without her, the house is quieter, lonelier, and 15 something. She showed me things no other person could, lessons that cannot be taught but only understood through an 16 like this. As I 17 back on the shadow she left, I question whether I could endure what she had. People say that what my family did for her was a great act of unconditional 18 and sacrifice, but in my eyes what she did for me was even greater. Though she is not 19 to me, she is a person I will always remember, not as an adopted sister but as a do 20 one. | ||||
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