Chapter 5: Web Servers Working with HTTP
1. A physical host, through the function of virtual host, can build multiple virtual servers, that is, build multiple web sites.
2. When multiple domain names are deployed on the same server ( same ip address ), when the client sends a request message, the host domain name or the URI of the domain name must be specified in the Host header .
3. The proxy is an application program that forwards the client's request message to the next server, and forwards the server's response message to the client.
4. Reasons for using a proxy:
①Using caching technology to reduce the flow of network bandwidth .
②Access control for specific websites .
③The main purpose is to obtain access logs .
5. Proxy is divided into caching proxy , transparent proxy and non-transparent proxy . When the caching proxy forwards the response, it will save the resource copy (cache) on the proxy ; the transparent proxy does not do any processing of the message, and it is a non-transparent proxy anyway.
6. Gateways can be connected using different communication protocols.
7. Tunnel: Establish a tunnel to ensure secure communication between the client and the server through encryption methods such as SSL . The tunnel is transparent, that is, no packet processing is performed.
8. Cache: Refers to the copy of resources saved in the client's local disk or proxy server .
Fuzzy knowledge points:
1. What is a gateway?
2. What is the role of the gateway?
3. What are the advantages of using a gateway?