Kiểm tra kiến thức Quizz 1

Which of the following services use TCP?

• FTP, HTTP, TFTP

• DHCP, SMTP

• DHCP, SMTP, TFTP

• HTTP, SMTP, FTP

What are the first 7 bytes returned by the web page to the browser?

• HTTP/1.×

• text/ht

What is the main cause of queue delay?

• Propagation delay.

• Arrival rate exceeds the output link capacity.

• Too many routers on the path.

• Large packet size.

Which of the following protocols does not belong to the application layer?

• POP

• FTP

• HTTP

• ARP

What mechanism combines multiple data streams on a link by transmitting in different frequency bands?

What protocol operates at the application layer?

• POP

• FTP

• HTTP

• ARP

Which mechanism combines multiple data streams over a link by transmitting in different frequency bands?

• Wavelength Division Multiplexing

• Time Division Multiplexing

• Frequency Division Multiplexing

• Packet Switching

Why are protocols organized into layers?

• To prevent modification

• To increase redundancy

• To allow distributed management

• To reduce complexity

Among the following pairs of protocols and service ports, which pair is correct?

• SMTP: TCP Port 110

• HTTP: UDP Port 80

• FTP: TCP Port 21

• Telnet: UDP Port 23

Given the following HTTP GET message: GET /cs453/index.html HTTP/1.1Host: gaia.cs.umass.eduUser-Agent: Mozilla/5.0 (Windows;U; Windows NT 5.1; en-US; rv:1.7.2) Gecko/20040804 Netscape/7.2 (ax) Accept:ext/xml, application/xml, application/xhtml+xml, text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5Accept-Language: en-us,en;q=0.5Accept-Encoding: zip,deflateAccept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7Keep-Alive: 300Connection:keep-alive. Identify the URL requested by the browser.

• http://gaia.cs.umass.edu/cs453/index.html

• http://gaia.cs.umass.edu/cs453/index.html/Gecko/20040804Netscape/7.2

• http://gaia.cs.umass.edu/Gecko/20040804Netscape/7.2/cs453/index.html

• http://gaia.cs.umass.edu