needs a quick detection solution about a connection loss without depending on TCP/IP

Please refer to the PMR 11064,69G,760.
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Customer would like to detect a connection loss when HEARTBEATTIMEOUT=3M (3 minutes) is expired without depending on TCP/IP when the target server running LPAR is down.
Because the detection of the connection failure is delay and the recovery operation time expands due to the replication state is remained as 'REPLICATE CONTINUOUS'.
In our test, the detection of the target LPAR down took 15 minutes until TCP/IP retransmission timeout.
In the current design, IIDR for IMS heartbeat processing does not detect the broken connection until the TCP/IP send fails.
The enhancement called 'heartbeat death' in the PMR 11064,69G,760 is as follows.
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What I think you're asking for here is a further enhancement to declare
"heartbeat death" if the source sends some number of heartbeats to the
target without a response. Currently, heartbeats are sent on the data
channel only when there is a lull in data flow for the subscription.
The data channel can be high volume, in-band with the data. To add
heartbeats into this flow could be problematic if there is a backlog of
changes to be processed by the target and a heartbeat is on the end of
that flow of data. It would be possible for replication to declare a
heartbeat death because the target isn't responding to the source's
heartbeat. Adding in heartbeat death (responses not received) could
lead to heartbeat timeouts in more ordinary situations where the target
isn't keeping up.

We would need to add the concept of a control channel to separate the
high-importance, low-volume messages like heartbeats from the
lower-importance, high-volume messages like database change messages.
This would allow the source and target to send heartbeats independently
at the heartbeattimeout and for each side to declare the other lost
after some frequency of sending a heartbeat without detecting a
receipt. This is beyond the scope of what was intended for the
original HEARTBEATTIMEOUT and not a trivial change. If I've accurately
captured what you're requesting you should open an RFE for that change.
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