Calendar Agent - Strange Connection

Hi Mac Folks

I am not sure if anyone here ever noticed the same issue of CalendarAgent, an OS X process running in the background for the Calendar application. What I have observed is that the process not only connects to Apple servers in California but also connects to a strange server on Optus (my ISP) network in Australia.

I used Mavericks' built-in utility NETTOP to capture the TCP connections, the screenshots are as below.

As shown above, the IP addresses for Apple servers are fixed to17.151.224.47 and 17.247.155.172 while the Optus IP for the third connection varies, always. The connections are always on HTTPS over port 4433.

I called AppleCare telling the issue and my concern, but the level-one support engineer told me that it is normal as my ISP is Optus hence all information must be going through an Optus server and blah blah. It was simply nonsense and I was really speechless.

The case was eventually escalated to the US side, an AppleCare Senior Advisor there also had no idea why this could be like that but promised to forward the request to their dev team for further investigation. He also could not reproduce the same thing on his EI Captain as the utility NETTOP is not available on the new OS. True?

FYI - As shown below, I do have an Australian Holidays subscription under the "Other" category in Apple Calendar, but it is explicitly subscribed to https://p10-calendars.icloud.com, which is pointed to one of the above Apple IPs on Akamai CDN and obviously not related to the strange Optus IPs.

Any comments please?

Thanks,

B