|Network| How to monitor the network traffic of the specific application

If we want to write a service in the Android framework, how can we do ?
There are some things we should know before starting to implement.
– what is UID in Android ? what’s different with Linux UID ?
– what is the relationship between UID and PID ?
– how can we use libpcap for Applications in the embedded system ?

This article will answer those questions and point out a direction.

|Network| My first XDP BPF code

BPF is a famous system performance tool. Specially, it is powerful for network engineers.
Recently, I attend a study group to talk about this topic.
https://hackmd.io/@yenWu/BJUR6cgWI

But, what is XDP? What is its relationship between BPF and XDP?
XDP: eXpress Data Path, exists in the network driver layer. BTW, only in RX. Therefore, with this tool, we can manage packet very early.(before traffic control)

This article is a note for setting up and testing an example.