By default tcp idle timeout is 1:0:0 hh:mm:ss. If in case you need to modify it you can do it by MPF (Modular Policy Framework). Let us setup a custom timeout when traffic is coming from particular host 10.77.241.129.
!— Match the traffic using the access-list —!
object-group service DM_INLINE_TCP_1 tcp
port-object eq www
port-object eq ssh
port-object eq telnet
access-list outside_mpc extended permit tcp host 10.77.241.129 <source ip> any object-group DM_INLINE_TCP_1
!— Define the class map Cisco-class –!
match access-list outside_mpc
!— Call this class-map into policy map and set the connection reset after 10 min when traffic is coming from particular host —!
set connection timeout idle 0:10:00 reset
!— Apply the policy-map Cisco-policy on the interface. —!
service-policy Cisco-policy interface outside
If you need to modify the tcp timeout session globally across the device you use do it using command. All the time is in hh:mm:ss format.
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02