Question

Are there any differences between external domains, and subdomains when using EasyXDM?

I am wondering about:

• Security Issues
• Cross Browser Support
• Speed
• Anything minor or major

I really can’t find much information about this, so I figure that it must be the same?

To explain further which one is the best setup of these:

1. example.com <-> sub.example.com
2. example.com <-> sub.other.com

Answer 1

There is one thing that make this thing easier, I found document.domain:

There is one exception to the same origin rule. A script can set the
value of document.domain to a suffix of the current domain. If it does
so, the shorter domain is used for subsequent origin checks.

For example, assume a script in the document at
http://store.company.com/dir/other.html executes the following
statement: document.domain = “company.com”;

After that statement executes, the
page would pass the origin check with
http://company.com/dir/page.html. However, by the same reasoning,
company.com could not set document.domain to othercompany.com.

Source: https://developer.mozilla.org/en-US/docs/Same_origin_policy_for_JavaScript