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 ## 安全控制
 
 ### 消息完整性校验
-![checksum](/path/to/img.jpg)
+![checksum](http://img10.static.yhbimg.com/goodsimg/2015/09/15/08/01391f6bef99e5d032a9e91f865bfede6d.jpg?imageMogr2/thumbnail/420x560/extent/420x560/background/d2hpdGU=/position/center/quality/80)
 
 ### 会话控制
 ![session control](http://git.dev.yoho.cn/yoho-documents/api-interfaces/blob/master/security/session-control.jpg)
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