icmpTypeV4: "" | "communication-prohibited" | "destination-unreachable" | "echo-reply" | "echo-request" | "fragmentation-needed" | "host-precedence-violation" | "host-prohibited" | "host-redirect" | "host-unknown" | "host-unreachable" | "ip-header-bad" | "network-prohibited" | "network-redirect" | "network-unknown" | "network-unreachable" | "parameter-problem" | "port-unreachable" | "protocol-unreachable" | "redirect" | "required-option-missing" | "router-advertisement" | "router-solicitation" | "source-route-failed" | "timestamp-reply" | "timestamp-request" | "TOS-host-redirect" | "TOS-host-unreachable" | "TOS-network-redirect" | "TOS-network-unreachable" | "ttl-exceeded" | "ttl-zero-during-reassembly" | "ttl-zero-during-transit"