Manage TD entries using periodic lifetime refresh

[mjkoster]

We might point out that using PUT on a registered TD location with an empty payload refreshes the lifetime of the TD on the server, without changing the registered TD.

A good way to manage TD lifetime is to set up your registration client to periodically refresh the lifetime of all currently exposed thing TDs by sending a PUT to each TD location e.g. every 300 seconds.

Then, set the lifetime to something greater, like 600 seconds (?lt=600)

If the server dies or shuts down, the registration will eventually time out.

It's a good idea to track your TDs and delete them when you're shutting down the server also.