Liveliness from sample update frequency?

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Liveliness from sample update frequency?

We are planning on having a point-to-point transport between two Router services that will be over a low-bandwidth communication path.  Because of this, we want to disable all of the discovery traffic and as much of the "meta" traffic as possible.  Given this, is there a way to configure reader QoS such that it detects liveliness based solely receipt of instance samples?  Put another way, is there a way to eliminate liveliness assertions and still have liveliness?

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You may want to experiment with the DEADLINE QoS policy. Your data would need to be written/read at a defined rate, then a deadline longer than that rate can be applied at the reader and/or writer. If there is a gap in time greater than the deadline period where samples are not read or written, the deadline status listeners are triggered for your application to process on its own. I don't believe entities are directly alerted to missed deadlines of their associated remote entities, which sounds like what you want (though they can be locally alerted if a deadline is applied on each side). 

In general, for constrained links between routing services you may also want to look into batching, time based filters, translating multiple topics into a single topic, and general discovery optimizations. (depending on your requirements)

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DEADLINE looks like a good way to address our design concerns.  Thanks for pointing that out.