The website needs to speed up the access speed of the website. The main means are the use of CDN and reverse proxy.
The basic principle of SDN and reverse proxy is cache, the difference
1. The CDN is deployed in the computer room of the network provider, so that when users request website services, they can obtain data from the computer room of the network provider closest to themselves;
2. The reverse proxy is deployed in the central computer room of the website, when the user request arrives After the central computer room, the reverse proxy server of the server accessed first, if the resource requested by the user is cached in the reverse proxy server,
it will be directly returned to the user.
These two technologies are used to: on the one hand, speed up user access, and on the other hand, reduce the load pressure on the back-end server.
In actual development, companies will use third-party CDN services, and Alibaba CND can directly bind and manage the domain name, and charge according to the amount.
You can also use the ELB service of the reverse proxy cluster service provided by Amazon.
Details
1. When a reverse proxy
user makes a request, it first sends the request to the proxy server, and then the proxy server requests the real server according to the algorithm, and finally returns it to the user. This approach, one is to improve security; the
other is to share user requests through multiple real servers to achieve load balancing.
2.
Load balancing The emergence of load balancing is to reduce the pressure on a single server as much as possible through horizontal expansion. Common WEB-level load balancing solutions include hardware F5, Nginx proxy, LVS, and load
balancing services of various cloud providers (such as AWS's ELB service). The server that actually provides the service is usually connected behind the load balancing. For example, through the ELB service, the traffic can be evenly shared, thereby reducing the pressure on the stand-alone server.