Network topology exhibit： You work as a network administrator at . You study the network topology exhibit carefully. is a small company that has an existing enterprise network consisting of two switches named 1 and 2. The network topology schemata indicates their layer 2 mapping. VLAN 40 is a new VLAN that will be used to provide the shipping personnel access to the server. For security reasons， it is necessary to restrict access to VLAN 20 in the following manner： Users connecting to 1’s port must be authenticate before they are given access to the network. Authentication is to be done via a Radius server： Radius server host： 172.120.39.46 Radius key： key Authentication should be implemented as close to the host device possible. Devices on VLAN 20 are restricted to in the address range of 172.120.40.0/24. Packets from devices in the address range of 172.120.40.0/24 should be passed on VLAN 20. Packets from devices in any other address range should be dropped on VLAN 20. Filtering should be implemented as close to the server farm as possible. The Radius server and application servers will be installed at a future date. You have been tasked with implementing the above access control as a pre-condition to installing the servers. You must use the available IOS switch features.
非平衡凝固
空中交通管制单位为飞行中的民用航空器提供的空中交通服务中含有（） ["导航服务；","机场保障服务；","飞行情报服务"]
某从事玩具开发的股份有限公司聘任下列何人员为公司董事的决议有效（）？ ["某工商局副局长吴某；","张某，因交通肇事罪被判处刑罚已执行期满五年；","年满15周岁有三项发明专利的赵某；","李某，因治病负债20万元。"]
一个C类IP地址最多可容纳（）主机。一个C类网络能够容纳多少台主机？ ["1677216","1677214","254","16382"]
Internet起源于美国的（）网络。
