Dubbo is Alibaba open source distributed service framework remote invocation framework , in the transmission of data between the network , you need communication protocols and serialization.

Dubbo supports dubbo, rmi, hessian, , and its communication efficiency is higher than WebService and Java comes with serialization.

Based on compactedjava, nativejava, fastjson, dubbo, fst, hessian2, kryo, which defaults to hessian2. which java, compactedjava, nativejava belongs to the native java serialization.

hessian2 serialization: hessian is a cross-language efficient way to serialize binary. But here it's not actually native hessian2 serialization, it's modified by Ali, and it's the serialization method enabled by default for dubbo RPC.

json serialization: there are currently two implementations, one is the use of Ali's fastjson library, the other is the use of dubbo's own implementation of a simple json library, but its implementation is not particularly mature, and json text serialization performance is generally not as good as the above two binary serialization.

java serialization: mainly using the JDK comes with the Java serialization implementation, performance is very poor.