What types of in-network caching mechanisms are there?

In computer networks, caching mechanism is a common technology used to speed up data transmission and reduce access pressure to the original data source. The in-network caching mechanism is usually undertaken by an intermediate device (such as a proxy server, cache server or router). It can be divided into many types according to the cache location and working methods. Common ones include:

1. Proxy server caching: The proxy server is usually located between the client and the original server and can cache static content such as Web pages, pictures, videos, etc. that have been visited. When the client requests the same content again, the proxy server can directly return the cached content, reducing access to the original server, reducing latency and network bandwidth usage.

2. Content Delivery Network (CDN) Cache: CDN is a network architecture that provides fast content delivery by deploying caching nodes located around the world. CDN cache can store static content and select the nearest cache node for content transmission based on user location and network conditions, thereby improving the access speed and stability of the content.

3. Router cache: Routers can use cache to store recently passed packets or routing information to speed up the forwarding of subsequent packets. This kind of cache is usually used to store routing tables, ARP tables and other information to reduce the router's query frequency for backbone links and improve routing performance.

4. DNS caching: DNS servers can cache the mapping relationship between recently resolved domain names and IP addresses to speed up subsequent domain name resolution. This cache can exist on your local computer, your ISP's DNS server, or a dedicated DNS cache server.

5. Accelerator cache: Some devices (such as accelerators) designed to accelerate specific applications or protocols may use cache to store related data to reduce the latency and latency of application layer protocol interactions. Bandwidth usage.

The above are common types of in-network caching mechanisms. They effectively improve the performance and availability of network services by storing and reusing data.