First, fill in the blanks (2 points per empty, a total of 20 points) 1. Computer network system consists of communication subnets and <> subnets. 2. The first phase of the development of computer network system is the online system, essentially the <> system. 3. Abstract syntax is a description of data <>. 4. Network security, vulnerability refers to the weaknesses of <> in the network system. 5.ISP is a mechanism to master Internet <>. 6. The media access control method of TOKEN BUS and its corresponding physical specification is defined by the <> standard. 7. When the datagram is transmitted in a physical network, the IP address is converted to the <> address. 8. Communication line connection is a bit-point and <> two ways. 9. The LAN protocol divides OSI to the data link layer into mac sub-layers and <> sub-layers. 10. Three wired media commonly used in computer networks are <>.
Second, the choice questions (1 point for each question, a total of 10 points) 1. The protocol structure of the LAN is generally not included <>. A, network layer B, physical layer C, data link layer D, media access control layer 2, resources that can be shared in computer networks include <>. A, hardware, software, data, communication channel B, host, peripherals, software, communication channel C, hardware, procedures, data, communication channel D, host, program, data, communication channel 3, and network protocol main elements are <> . A, data format, encoding, signal level B, data format, control information, speed matching C, grammar, semantic, synchronization D, encoding, control information, synchronization 4, when a dedicated line communication is used, the communication stage can be saved. ". A. Establish communication line B, establish data transmission link C, transmit communication control signals and data D, two parties confirm the end 5, and both end users transmit files, should belong to the following OSI <> layer processing? A, represent layer B, session layer C, transport layer D, application layer 6, and various networks require <> when the physical layer interconnect. A, the data transfer rate and the link protocol are the same b, the data transfer rate is the same, the link protocol can be different, the data transmission rate can be different, the link protocol is the same D, the data transfer rate and the link protocol can be different 7, intranet Technology is mainly composed of a series of components and technologies, and the core of intranet is <>. A, ISP / SPX B, PPP C, TCP / IP D, SLIP8, data blocks in the data link layer are often referred to as <>. A, information B, packet C, frame D, bit stream 9, if the bit transmission rate of 64 kbps can be achieved by a physical medium, the analog signal is encoded by the pulse code modulation method, and 256 quantization levels are used each time the sample is quantified. Then allow the number of times the sample per second is <>. A, 256 times B, 512 times C, 128 times D, 8000 times 10, and the ratio code coding efficiency of M is <>. A, M / N B, CMN LOG2 (m / N) C, M / (N M) D, LOG2CNM / N
Third, the noun explanation (2 points for each question, a total of 10 points) 1, transparent transmission 2, half-duplex communication 3, data communication 4, QoS 5, IPv4 address
Fourth, calculation questions (6 points for each question, a total of 30 points) 1. Briefly describe the main features and working principle of the 56K modem. 2. Briefly describe the main content of network management. 3. Briefly describe the principle and role of VLANs. 4. Examples illustrate the working principle and implementation process of VLSM. 5, compare the differences between connection and connectionless services.
