NO.90045

The Internet is based on a connectionless end-to-end packet service, which traditionally provided best-effort means of data （）using the Transmission Control Protocol/Internet Protocol Suite. Although the （）design gives the Internet its flexibility and robustness, its packet dynamics also make it prone to congestion problems,especially at （）that connect networks of widely different bandwidths.The initial QoS function set was for internet hosts.One major problem with expensive wide-area（）links is the excessive overhead due to small Transmission Control Protocol packets created by applications such as telnet and rlogin. The Nagle （），which solves this issue,is now supported by all IP host implementations.

第 1 问

A. transformation

B. transportation

C. processing

D. progressing

第 2 问

A. connectionless

B. connection

C. connection-oriented

D. connotation

第 3 问

A. hosts

B. switches

C. routers

D. computers

第 4 问

A. interconnection

B. network

C. internet

D. web

第 5 问

A. technology

B. problem

C. structure

D. algorithm

参考答案: B A C B D

详细解析:

因特网是基于无连接的端到端的分组服务，这种传统上提供的尽力而为的服务意味着使用传输控制协议或因特网协议集进行数据传输。虽然无连接的设计使得因特网具有更多的灵活性和坚强性，但是它的分组动态也使得它更容易产生拥塞问题，特别是在广泛使用的连接不同带宽网络的路由器中尤为如此。最初的QoS功能是由因特网主机实现的。伴随着昂贵的广域网络链路的一个主要问题是，由于telnet 和rlogin等应用产生的很小的传输控制协议分组所引起的过多的开销。解决这个问题的Nagle 算法现在已经得到了所有IP主机实现的支持。