A communication system for reporting a compromised state in one-way transmission, comprising: a receiving server, and a communication device communicatively connected to the receiving server, wherein the communication device comprising: a first port, receives a packet; an error checking circuit coupled to the first port, wherein the error checking circuit checks a header of the packet; a data inspection circuit coupled to the first port and the error checking circuit; a first unidirectional coupler coupled to the first port and the error checking circuit, wherein the first unidirectional coupler is enabled before the header being checked; and a second unidirectional coupler coupled to the first port and the error checking circuit, wherein the error checking circuit disables the first unidirectional coupler and enables the second unidirectional coupler in response to an error being in the header such that the packet is transmitted from the first unidirectional coupler to the receiving server incompletely, wherein the receiving server receives the packet from the first unidirectional coupler and outputs the compromised state according to the received packet in response to determining the received packet incomplete, wherein the data inspection circuit inspects whether data of the packet is correct in response to the error not being in the header. a receiving server, and a communication device communicatively connected to the receiving server, wherein the communication device comprising: a first port, receives a packet; an error checking circuit coupled to the first port, wherein the error checking circuit checks a header of the packet; a data inspection circuit coupled to the first port and the error checking circuit; a first unidirectional coupler coupled to the first port and the error checking circuit, wherein the first unidirectional coupler is enabled before the header being checked; and a second unidirectional coupler coupled to the first port and the error checking circuit, wherein the error checking circuit disables the first unidirectional coupler and enables the second unidirectional coupler in response to an error being in the header such that the packet is transmitted from the first unidirectional coupler to the receiving server incompletely, wherein the receiving server receives the packet from the first unidirectional coupler and outputs the compromised state according to the received packet in response to determining the received packet incomplete, wherein the data inspection circuit inspects whether data of the packet is correct in response to the error not being in the header. a first port, receives a packet; an error checking circuit coupled to the first port, wherein the error checking circuit checks a header of the packet; a data inspection circuit coupled to the first port and the error checking circuit; a first unidirectional coupler coupled to the first port and the error checking circuit, wherein the first unidirectional coupler is enabled before the header being checked; and a second unidirectional coupler coupled to the first port and the error checking circuit, wherein the error checking circuit disables the first unidirectional coupler and enables the second unidirectional coupler in response to an error being in the header such that the packet is transmitted from the first unidirectional coupler to the receiving server incompletely, wherein the receiving server receives the packet from the first unidirectional coupler and outputs the compromised state according to the received packet in response to determining the received packet incomplete, wherein the data inspection circuit inspects whether data of the packet is correct in response to the error not being in the header.