SMPP Enquire Link

I'm currently using Kannel to connect to an SMSC via
SMPP 3.4. I've been perusing the log files created for
the SMSC connections and it seems that the
enquire_link PDU is sent twice. The first enquire_link
PDU is sent, then a response comes back and a second
later another enquire_link PDU is immediately sent
out. Is this a desired effect?

Thanks


		
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