# C5G_Tests.ttcn * external interfaces * NG-C: SCTP/NGAP(emulates gNB or/and g-eNB side) towards AMF * NG-U: UDP/GTPv1U (emulates gNB or/and g-eNB side) towards UPF * Internet: emulates the Internet side from/to UPF {% dot 5gc_tests.svg digraph G { rankdir=LR; ATS [label="ATS\nC5G_Tests.ttcn"]; AMF [label="AMF\open5gs-amfd",shape="box"]; SMF [label="SMF\nopen5gs-smfd"]; UPF [label="UPF\nopen5gs-upfd"]; ATS -> AMF [label="NGAP"]; ATS -> UPF [label="GTPv1U",style="dashed"]; AMF -> SMF [label="GTPv2C"]; SMF -> UPF [label="PFCP"]; } %}