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.版本之后采用了Netfilter机制，它是在内核中扩展各种网络服构化底层框架。

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.

现了协同网络公系统，给出了使用JAVA语言工作流现，包括工作流核心接口类、主要类现以及工作流引擎现，并在该工作流基础上，现了该系统公文流转、审批流程设置等主要公业。