假设某计算机有1MB的内存，并按字节编址，为了能存取其中的内容，其地址寄存器至少需要(9)位。为使4字节组成的字能从存储器中一次读出，要求存放在存储器中的字边界对齐，一个字的地址码应(10)。若存储周期为200ns，且每个周期访问 4B，则该存储器的带宽为(11)bit/s。假如程序员可用的存储空间为4MB，则程序员所用的地址为(12)，而真正访问内存的地址为(13)。

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Packet switching is a method of slicing(71) messages into parcels called "packets," sending the packets along different communication(72) as they become available, and then reassembling the packets(73) they arrive at their destination. Prior to the development of packet switching, early computer networks used leased, dedicated telephone circuits to(74) with terminals and other computers. In circuit-switched networks such as the telephone system, a complete point-to-point(75) is put together, and then communication can proceed.

URL consists of three parts: the protocol(75), the DNS name of the host (www.csai.cn) and the file name (index.html).

The essence of(74) is the invention of a hierarchical, domain-based naming scheme. It is primarily used for mapping host names and e-mail destinations to IP addresses.

As one of Gigabit Ethernet, 1000Base-Tuses(73) pairs of UTP.

To reduce their design complexity, most networks are organized as a stack of(72), each one built upon the one below it.

(71) are privately-owned networks within a single building or campus of up to a few kilometers in size.