Hello guoqiang.li
Thank you for your question.
However, the Small Business Support Community is limited to Cisco Small Business Products and the EA4500 is not a Cisco Small Business Product. The EA4500 is considered as a Cisco Home Product.
In the next link you will find the area that may help you further with your question.
http://homesupport.cisco.com/en-us/support/routers/EA4500
Best regards,
Diego Rodriguez
Cisco Small Business Community Engineer
