Linux system kenel adopts the Netfilter mechanism ,which is a structural bottom frame for expanding various network service after 2.4 version.

Linux系统内核自2.4.版本之后采用Netfilter，它是在内核中扩展各种网络服务结构化底层框架。

Workflow realization base on JAVA was given, including kenel interface, main classes and workflow engine.File flow, examine and approve flow function of the system were realized based on the workflow.

现协同网络税务办公系统，给出使用JAVA语言工作现，包括工作核心接口类、主要类现以及工作引擎现，并在该工作基础上，现该系统公文转、审批程设置等主要办公业务。