According to your config, server should disconnect idle clients after
30 seconds timeout. Considering that HTTPURLConnection may decide to
retry the request - it may take 2x longer.
Is it possible for you to make a HTTP packets dump using wireshark [1]
for example, so we can check the traffic?
Thanks.
WBR,
Alexey.
[1]
http://www.wireshark.org/download.html