# Extension 专题

Neutron中的扩展，主要用于实现原先标准API中并不支持的扩展的网络服务，包括路由器、防火墙、vpn等等。

扩展包括三种类型：资源扩展、行动扩展和请求扩展。

资源扩展意味着在网络中引入新的资源和相应的属性；行动扩展是为标准的API控制器添加行动支持；请求扩展是为API控制器提供额外的请求和响应支持。


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