![]() ![]() His router stamps its own IP address on the packet as the âfromâ IP address, and sends it off across the Internet. Bobâs local router receives all these 1âs and 0âs and interprets them as a packet, from Bobâs own MAC address, and destined for Aliceâs IP address.The body contains his request for Aliceâs server application. The header contains an immediate destination of his local routerâs MAC address, with a final destination of Aliceâs IP address. These bits form some information, containing a header and body. Bobâs computer sends along a stream of 1 and 0 bits, indicated by high and low voltages on a wire.When one machine wants to talk to another machine, something like the following exchange takes place: Bob uses a desktop computer, which is trying to connect to Aliceâs server. To give you some idea of the infrastructure required to get information to your browser, letâs use the following example. However, web scraping requires stripping away some of this shroud of interface, not just at the browser level (how it interprets all of this HTML, CSS, and JavaScript), but occasionally at the level of the network connection. In fact, I would argue that itâs fantastic that computer interfaces have advanced to the point where most people who use the Internet donât have the faintest idea about how it works. We donât want to think about what, exactly, the network is doing every time we open a browser and go to, and, these days, we donât have to. If you havenât spent much time in networking, or network security, the mechanics of the Internet might seem a little mysterious.
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