|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.