I have connected a peer and i can see the sctp association being setup correctly using "cat proc/net/sctp/assocs"

When i power-off my peer, the sctp assocs are getting deleted after about 3 minutes. Could someone please explain why?

I have captured packets using tcpdump and it shows that 2 heartbeat messages were sent from server. The delay between those packets is 70 seconds though the value of hb_interval in my kernel is 5000.

association_max_retrans is set to 2 and rto_min,rto_max and rto_initial are all set to 100000, path_max_retrans is set to 5.