ball buster 百度网盘:请朋友们帮忙翻译一下,谢谢拉

Before continuing, let’s do a back-of-the-envelope calculation to estimate the amount of time from a client requesting the base HTML file until the file is received by the client. To this end we define the round-trip time(RTT), which is the time it takes for a small packet to travel form client to server and then back to the client. The RTT includes packet-propagation delays(These delays were discussed in Section 1.6) Now consider what happens when a user clicks on a hyperlink. This causes the browser to initiate a TCP connection between the browser and the Web server; this involves a “three-way handshake”-the client sends a small TCP message to the server, the client sends a small TCP message to the server, the server acknowledges and responds with a small message, and, finally, the client acknowledges back to the server. One RTT elapses after the first two parts of the three-way handshake .After completing the first two parts of the handshake, the client sends the HTTP request message into the TCP connection, and TCP “piggybacks” the last acknowledgment(the third part of the three way handshake) onto the request message. Once the request message arrives at the server, the server sends the HTML file into the TCP connection. This HTTP request/response eats up another RTT. Thus, roughly, the total response time is two RTTs plus the transmission time at the server of the HTML file