Ethernet局域网采用的媒体访问控制方式为()。
A、CSMA
B、CSMA/CD
C、CDMA
D、CSMA/CA
参考答案:B
某城镇一电影院春节期间放映新片,场场爆满,每场3小时,场次间隔仅15分钟,而且管理紊乱,吃东西、抽烟相当普遍。大多数观众散场后均感到疲乏、头晕、头痛,甚至恶心不适等,其原因最可能是()
A.CO中毒
B.室内通风不好,CO浓度过高
C.放映时间过长
D.电影院建筑质量差
E.传染病流行
astute service providers realize that the continued support of legacy X.25 and asynchronous network element using separate operations network is cost (141) . For example, the maintenance of multiple networks can require additional staff. Often, this staff must be trained on multiple vendor technologies, sometimes requiring parallel groups specializing in each (142) . Hence, additional maintenance procedures must be maintained and administrative records are (143) . The duplication of transport facilities to carry (144) network traffic is an inefficient use of resources. And not surprisingly, more technologies installed in a central office means the necessity for more physical space and an increase in power connections and power consumption, migration of these (145) network elements to IP-based DCns is alogical strategy.
A.prohibitive
B.feasible
C.connective
D.special