RN-171/RN-131 Wifly module many of them are using to connect to the wireless network is a 32bit powerhouse that is perfectly capable of performing and posting the measurements by itself! They are all too happy to leave the Arduino banging away in a main loop, running off a 9V battery via the linear regulator, and ignoring the perfectly capable processor on the Wifly itself. I like Arduino, but I much prefer using the right tool for the right job!
Gets the right general idea using sleep modes and reduced hardware but the final solution gets predicted 33.3 Hour run time off 6 AA batteries even with optimisations, logging at 1 minute intervals. Sleep mode is almost 1mA.
I notice from other site that we need to configure both the host ip address and hostname for http request to work . However in your example only ip address is configured. Is it the case that either the hostname or the ip address is required ?
I am thinking of using in in a small home monitoring project but e server i have doesnt have a static ip address. Thanks for clarifying.