digraph G {
rankdir=TB
labelloc=t; label="PFCP CP peer FSM\nControl Plane side, managing association with remote UP peer"

cp [label="CP function",shape="box"]

cp -> DISABLED [label="cp_peer_alloc()"]
cp -> WAIT_ASSOC_SETUP_RESP [label="cp_peer_associate()"]

txrx [label="PFCP socket",shape="box"]
WAIT_ASSOC_SETUP_RESP -> txrx [label="tx_assoc_setup_req()",style=dotted]
txrx -> WAIT_ASSOC_SETUP_RESP [label="EV_RX_ASSOC_SETUP_RESP",style=dotted]
WAIT_ASSOC_SETUP_RESP -> ASSOCIATED [label="Assoc Setup Resp"]

WAIT_ASSOC_SETUP_RESP -> WAIT_ASSOC_SETUP_RESP [label="retry"]

heartbeat [label="PFCP heartbeat FSM",shape=box3d]
ASSOCIATED -> heartbeat [label="alloc()",style=dotted]
heartbeat -> ASSOCIATED [label="EV_HEARTBEAT_FAILURE",style=dotted]

txrx2 [label="PFCP socket",shape="box"]
txrx2 -> ASSOCIATED [label="EV_RX_ASSOC_UPDATE_REQ\n3GPP TS 29.244 6.2.7.3.1",style=dotted]
GRACEFUL_RELEASE -> txrx2 [label="tx_assoc_update_resp()",style=dotted]

cp_session [label="PFCP CP session FSM",shape=box3d]
cp -> ASSOCIATED [label="cp_peer_session_create()",style=dotted]
ASSOCIATED -> cp_session [label="cp_session_create()",style=dotted]
cp -> cp_session [style=invisible,arrowhead=none]

ASSOCIATED -> GRACEFUL_RELEASE [label="Association Update\nindicating graceful release"]

cp -> ASSOCIATED [label="cp_peer_release()",style=dotted]
ASSOCIATED -> term [label="cp_peer_release()\nHeartbeat failure"]

ASSOCIATED -> WAIT_ASSOC_SETUP_RESP [label="Heartbeat failure"]

GRACEFUL_RELEASE -> term
term [shape="octagon"]

}