oss上传字符串报错

请问私有云的oss 服务访问和公网的有什么区别吗？
我的oss上传文件的时候一直报一下错误：

[ResponseError]:
<?xml version="1.0" encoding="UTF-8"?>
<Error>
  <Code>SignatureDoesNotMatch</Code>
  <Message>The request signature we calculated does not match the signature you provided. Check your key and signing method.</Message>
  <RequestId>5BCB080EC7F0054F9B021A49</RequestId>
  <HostId>oss-cn-shanghai-clwang3-d01-a.cloud.echargenet.com</HostId>
  <OSSAccessKeyId>1tTIZ0LPFuQYUr9j</OSSAccessKeyId>
  <SignatureProvided>i66Db0W2y+xNFVPG3VDMqgzDjBU=</SignatureProvided>
  <StringToSign>PUT
application/octet-stream
Sat, 20 Oct 2018 10:48:46 GMT
/154003252663810001</StringToSign>
  <StringToSignBytes>50 55 54 0A 0A 61 70 70 6C 69 63 61 74 69 6F 6E 2F 6F 63 74 65 74 2D 73 74 72 65 61 6D 0A 53 61 74 2C 20 32 30 20 4F 63 74 20 32 30 31 38 20 31 30 3A 34 38 3A 34 36 20 47 4D 54 0A 2F 31 35 34 30 30 33 32 35 32 36 36 33 38 31 30 30 30 31 </StringToSignBytes>
</Error>