The iOS 11 Trust Store contains three categories of certificates:
- Trusted root certificates are used to establish a chain of trust that‘s used to verify other certificates signed by the trusted roots, for example to establish a secure connection to a web server. When IT administrators create Configuration Profiles for iPhone, iPad, or iPod touch, they don‘t need to include these trusted root certificates.
- Always Ask certificates are untrusted but not blocked. When one of these certificates is used, you‘ll be prompted to choose whether or not to trust it.
- Blocked certificates are believed to be compromised and will never be trusted.
使用itms-services安装iOS App
在iOS 7.1版本之后，通过itms-service安装应用时，要求itms-service协议后面的url的值即plist文件的地址必须为https地址，且设备必须信任此https服务器的SSL证书。
How Do You Trust Manually Installed Root Certificates in iOS?
If your users are on iOS 10.3, they will need to follow the following steps to trust a certificate included in a profile
- Ensure they have installed the profile on their device.
- Open Settings.
- Navigate to General and then About.
- Select Certificate Trust Settings.
- Each root that has been installed via a profile will be listed below the heading Enable Full Trust For Root Certificates. Users can toggle on/off trust for each root.
ssl,证书
原文：http://www.cnblogs.com/dqxu/p/7620229.html
