16. It satisfies client requests without involving the origin server A. Web cookies B. Web caches C. Web proxy D. Web stack 17.HTTP/3 doesn't include: A. security B. per object error C. congestion-control (more pipelining) over UDP D. connection-control (more pipelining) over UDP 18. Which option is correct for SMTP? A. uses UDP to reliably transfer email message from client B. command/request interaction (like ftp) C. mail server initiating connection to server, port 105 D. three phases of transfer: SMTP transfer of messages, SMTP handshaking (greeting), SMTP closure 19. Which one is wrong?! - cs-gw (128.119.240.254) 1 ms 1 ms 2 ms A. 3 delay measurements from gaia.cs.umass.edu to cs-gw.cs.umass.edu B. traceroute: gaia.cs.umass.edu to www.eurecom.fr C. Class B IPV4 Address D. Class C IPV4 Address 20. how to map between IP address and name, and vice versa? A. Domain Name System (DNS) B. IMAP provider retrieval C. Name server aliasing D. Distributed database 21.responsible for.edu: A. authoritative domain servers B. Top-Level Domain (TLD) servers C. Local ISP D. Name resolution 22.File distribution time, which option is wrong? A. time to send one copy: F/us B. min client download time: F/dmin C. dmin = min server download rate D. time to send N copies: NF/us 23.which option is correct? A. Transport layer provides logical communication between application processes running on different hosts B. receiver: breaks application messages into segments, passes to network layer C. sender: reassembles segments into messages, passes to application layer D. three transport protocols available to Internet applications: TCP, UDP, HTTP 24. use header info to deliver received segments to correct socket: A. multitasking at receiver B. multiplexing at receiver C. demultiplexing at receiver D. demultiplexing at host