Our company server is located in China and we used Filemaker make own ERP system. In China all our staff is using Filemaker Pro or Go to connect to the server, and of course there is no problem with connection. Latency is about 30-50 ms. But all our customers are from Russia or other countries, and they use Filemaker Webdirect. Sometime they even can't see the login layout, also latency is about 1200 or higher, packet loss is about 50%.
I think a problem is China Great Wall Firewall, and i don't know how we can let our customers have a good connection form other countries?
Ok. I found a good solution. I've implemented RESTfm open source php code that uses Filemaker server php and xml api. http://restfm.com/
I've tested it to fetch 1000 records with 13 fields in 3 countries. The longest request time was 8000 ms. It's more better than webdirect or connection through FM GO. Get or post 1 record is even faster and took only 1000 ms.
So right now I use like a PHP web service between my FM server and other apps. I also wrote 1 app for iOS, so our customers very happy.