Browsing the web
Enter google.com, who is this google.com
This question gets asked all the way down to our ISP(Internet Service Provider), like Verizon For users, you pay so you have internet.
ISP get the request and send them to DNS(Domain Name Server) server, it's like a phone book.
It has the list of all these URLs like google.com and has the address of them
DNS send off the request back through ISP
web browser like google chrome in this case gets 172.217.7.23
we recevie IP address
anything that's connected to the Internet has its own address (each laptop work now has IP address)
this Ip address allows the Internet to work
once we know the IP address, the browser sends off another request to Google Server
Google Server say, oh np let me give you my HTML, CSS, JS
then HTML, CSS, JS would be sent to the browser
Then browser would show the formal Google page
对于以上三步,
我们是否可以skip第一步
用第二步直接将IP address发送给Google server
同样可以得到第三步的formal Google page
Breaking Google
通过 View -> Developer -> Develper Tools
界面就变这样了
点击左上方的这个带poniter的标志
可以看到网页的各个模块, 可以自行改动模块
这就像我们改动了Google Server先前传过来的 HTML, CSS, JS文件
一旦我们再reques Google Server
则界面又会复原成Google Server 传来的 HTML, CSS, JS文件所展示的样子(如下图)
The Internet Backbone
We have Wifi from router
Router is connected to modem(If you sign up for Internet, you may have someone come to your house and install it
The modem has the signal towers that transmit signals
Is connected all the way to the ISP
IPS is connected to Internet backbone
all the files would go through this submarine cable(physical cable goes the bottom of see floor )
Traceroute
通过traceroute可以查到从自己家的home router出发到google server中间转战了多少个stop
Developer Fundamental
how to make websites load faster ?
location of server 越近越好
how many trips 越少越好
size of files 越小越好
What does a developer do ?