아주대학교 컴퓨터네트워크 퀴즈 TCPIP-1

1. (O/X) 다음 각 문항의 내용이 맞으면 O, 틀리면 X 를 적으시오. 단, X로 선택한 경우에는 이유를 함께 적으시오. 이유가 잘못된 경우에는 틀린 것으로 간주됩니다. 각 문항당 점수는 5점이며, 답을 잘못 적은 경우 경우에는 0점이 아닌 -5점을 받게 되니 주의하여 답을 작성하시오. (1) The Internet’s transport layer includes many protocols, such as the HTTP protocol (which provides for the transfer of files between two end systems), SMTP (which provides for the transfer of e-mail messages), and FTP (which provides for Web document request and transfer). (2) In a client-server architecture, there is an always-on host, called the client, which services requests from many other hosts, called servers. (3) The TCP service model includes a connection-oriented service and a reliable data transfer service, while UDP is connectionless, and provides an unreliable data transfer service (4) With persistent connections in HTTP, the server leaves the TCP connection open after sending a response. Subsequent requests and responses between the same client and server can be sent over the same connection. (5) FTP sends its control information on the same connection for exchanging data. (6) HTTP is mainly a pull protocolsomeone loads information on a Web server and users use HTTP to pull the information from the server at their convenience. On the other hand, SMTP is primarily a push protocolthe sending mail server pushes the file to the receiving mail server. (7) SMTP delivers the message from a sender’s mail server to recipient’s mail server, and the recipient can obtain the message from its mail box in its mail server using SMTP. (8) The root, TLD, authoritative and local DNS servers all belong to the hierarchy of DNS servers (9) When there are seven peers with IDs 1, 7, 16, 25, 33, 45, 63 in DHT-based P2P network, the peer 16 stores the key 6. (10) The port numbers ranging from 0 to 1023 are called well-known port numbers, which means that they are reserved for use by well-known application protocols such as HTTP and FTP. 2.(15점) OSI 7 layer를 상위에서 하위의 순서데로