Sometimes your network hick-ups and drops a connection. Sometimes a device glitches and stops talking. Sometimes things just get into a weird state, and while it's correct to complain, it's perhaps better to be resilient and try to clean up and try again. Let me tell you how the Cynical plugins deal with this.
Every Cynical plugin that manages network connections can tell that a connection to the device has failed. When it notices, it resets the connection, effectively restarting the device as if you had just turned it on. You will see an error message in the Indigo log to that effect. You should not see a network device getting "stuck" in some twilight state because of network trouble. This is automatic.
However, it's a peculiarity of the TCP protocol (which pretty much everything uses) that if neither side (Indigo or the device) has anything to say to the other, they won't actually say anything, and thus Indigo won't notice that a device connection has disappeared until it actually tries to talk to it again. Surprisingly often, the disconnects happen over night, and the sad realization hits you in the morning when you want something to work. For these cases, several of the Cynical plugins now sport a new checkbox in the device configuration, called Keepalive. If you turn on keepalives, the plugin will periodically say something to the device just as a means to say, "Are you still there, dear?" This means that with keepalive enabled, Indigo will find out pretty soon (within 15 minutes or so) if a connection has failed. This means your lost-at-night connection will have reset by the time you wake up in the morning.
Keepalive does one more thing: Since it's actually talking to the device and expecting an answer, it will catch any situation where the device just clams up and stops responding. That too is taken as an indication that something's wrong, so eventually the plugin will write an error message to the Indigo log and try to reset the device connection. This will even catch problems on serial connections. Don't expect miracles though - if the device is truly catatonic, the plugin's attempt to reset it will fail and you'll still have to pull the power or press some reset button or whatever it takes. But once you do, the plugin will re-establish its connection and start working again.
Keepalive applies only to Indigo devices that represent network or serial connections. Sub-devices (such as cameras for SecuritySpy, or zone devices of Denon receivers) "belong" to their main devices. When the main device resets, you'll get an error message for each sub-device, but they will reset along with their main device and become functional again.
At least that's the theory. Give it a spin if you like, and let me know how it works for you. It's obviously better to fix your networking problems rather than paper them over with reconnections, but it's better to fix problems than to just suffer. Keepalives are only sent (about once every 10 minutes) if nothing has been received from the device. They shouldn't cause you or your network any trouble.
Cheers
-- perry