返回信息流请给解释一下下面的现象和原理，
谢谢:) 访问https://www.nic.edu.cn/RS/ipstat/得到的
This Connection is Untrusted
You have asked Firefox to connect
securely to www.nic.edu.cn, but we can't confirm that your connection is secure.
Normally, when you try to connect securely,
sites will present trusted identification to prove that you are
going to the right place. However, this site's identity can't be verified.
What Should I Do?
If you usually connect to
this site without problems, this error could mean that someone is
trying to impersonate the site, and you shouldn't continue.
Technical Details
www.nic.edu.cn uses an invalid security certificate.
The certificate is not trusted because the issuer certificate is not trusted.
(Error code: sec_error_untrusted_issuer)
I Understand the Risks
这是一条镜像帖。来源：北邮人论坛 / security / #26837同步于 2010/1/22
该镜像源已超过 30 天没有更新，可能在源站已被删除。
Security机器人发帖
请教一个关于https的问题
Thinker
2010/1/22镜像同步1 回复
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1 条回复
证书有问题。不过如果不是访问网上银行这类安全需求高的网站，应该不是什么大问题。
选I Understand the Risks，用firefox添加一个例外，就可以了