题目内容
（请给出正确答案）
A.data link
B.network
C.transport
D.application
安装简答题APP，拍照搜题省时又省心！
更多“TCP works on the ________ laye…”相关的问题
The standard protocol used for sending Internet e-mail is called (). It works in conjunction with POP servers.
A、SMTP
B、WWW
C、TCP
D、UDP
【填空题】Each Internet （1）, called a host, is independent. Its operators can choose which （2） services to use and which （3） services to make available to the （4） Internet community. Remarkably, this anarchy by design works exceedingly well. IP is responsible for moving packet of data from （5） to node. IP forwards each packet based on a four-byte destination （6） (the IP address). The Internet authorities assign ranges of numbers to different organizations, The organizations （7） groups of their numbers to departments. （8） is responsible for verifying the correct delivery of data from （9） to server. Data can be lost in the intermediate （10）. TCP adds support to detect error or lost data and to trigger retransmission until the data is correctly and completely received.
● A glue that holds the whole Internet together is the network layer protocol,(71). Unlike most older network layer protocols, it was designed from the beginning with internetworking in mind. Its job is to provide a -(72) way to transport datagrams from source to destination, without regard to whether these machines are on the same network or whether there are other networks in between them.
Communication in the Internet works as follows. The (73)layer takes data streams and breaks them up into datagrams. Each datagram is transmitted through the Internet, possibly being fragmented into smaller units as it goes. When all the pieces finally get to the destination machine, they are reassembled by the
(74) layer into the original datagram. This datagram is then handed to the transport layer, which inserts it into the receiving process' input stream.
An IP datagram consists of a header part and a text part. The header has a (75) part and a variable length optional part.
(71) A. IP (Internet Protocol)
B. IP (Interworking Protocol)
C. TCP (Transport Control Protocol)
D. TCP (Transfer Communication Protocol)
(72) A. best-quality
B. quality-guaranteed
C. connection-oriented
D. best-efforts
(73) A. data link
B. transport
C. network
D. application
(74) A. data link
B. transport
C. network
D. application
(75) A. 40-byte fixed
B. 64-byte fixed
C. 20~64 bytes variable
D. 20-byte fixed
A.work; work
B.works; work
C.work; works
D.works; works
A．It becomes smaller and works faster.
B．It becomes larger and works faster.
C．It becomes larger and works slower.
D．It becomes smaller and works slower.
He works very ().
A.hard
B.hardly
C.harder
D.harded
A.works on
B.works away
C.works out
D.calculates
Greenpeace is an international (organize) ______ that works to protect the environment.
为了保护您的账号安全，请在“简答题”公众号进行验证，点击“官网服务”-“账号验证”后输入验证码“”完成验证，验证成功后方可继续查看答案！
微信搜一搜
简答题
微信搜一搜
简答题
如搜索结果不匹配，请 
