A user clicks on the link www.msn.com/index.html. Accordingly, the browser asks the cache server for this page, which is available at the cache from Wed 01 Jun 2017 22:54:43 GMT and it is modified yesterday. Write the HTTP 1.1 conditional GET request/response messages sent/received by the cache server. The answer must include the TCP connection (telnet) command and the necessary headers (if exist).

QUESTION 13 Fill the blank With the TCP server, there is a welcoming socket, and each time a client initiates a connection to the server, a new socket is created. Thus, to support n simultaneous connections, the server would need sockets. O n-1 On O n+1 01

QUESTION 18 Code an Express route that   Accepts all paths Accepts all HTTP request methods With a callback that does not generate a response message but passes control to subsequent routes

Explain what this rule does: alert tcp any any -> 192.168.1.0/24 80 (content:”|A1 CC 35 87|”; msg:”accessing port 80 on local”).

What does it mean when an HTTP query has a header field of "Connection: keep-alive"? a. The client can keep the TCP connection open for future requests/responses if this is supported by the server. O b. Use UDP for additional connections to the server. c. Continually send an object from the server to the client until the client has acknowledged receipt of the requested object. O d. Use the QUIC protocol for this connection.

True or False 1. After fast retransmit is invoked, fast recovery cuts the slow start period in half 2. A host sends a segment with a sequence number 35 and a payload of 5 Bytes. The ACK number in that segment is 40 3. TCP segments can only be lost when router queues overflow. Please explain if possible， Thank you!

Question 23 A client's browser sends an HTTP request to a website. The website responds with a handshake and sets up a TCP connection. The connection setup takes 2.1 ms, including the RTT. The browser then sends the request for the website's index file. The index file references 8 additional images, which are to be requested/downloaded by the client's browser. Assuming all other conditions are equal, how much longer would non-persistent HTTP take than persistent HTTP? (Give answer in milliseconds, without units, rounded to one decimal place. For an answer of 0.01005 seconds, you would enter "10.1" without the quotes.)

It is necessary to provide dependability and other TCP features on UDP in order for the QUIC protocol to be capable of providing HTTP True False 00.

import socket def authenticate_user(tcp_socket):    while True:        response = tcp_socket.recv(1024).decode()        print(response)        username = input()        tcp_socket.sendall(username.encode())        response = tcp_socket.recv(1024).decode()        print(response)        password = input()        tcp_socket.sendall(password.encode())        auth_response = tcp_socket.recv(1024).decode()        if "successful" in auth_response:            print(auth_response)            return True        else:            print(auth_response) def receive_items(tcp_socket):    while True:        response = tcp_socket.recv(1024).decode()        if "Item List:" in response:            print(response)            while True:                item = tcp_socket.recv(1024).decode()                if not item.strip():                    break                print(item)            break def select_items(tcp_socket):    selected_items = []    while True:        item_id = input("Select item by entering…