電磁環境に起因する情報セキュリティ: It檆器のemissionとtempestセキュリティ

摘要

Generally, active electronic devices emit slightly unintentional electromagnetic noise. From long ago, electromagnetic emission levels have been regulated from the aspect of electromagnetic compatibility (EMC). Also, it has been known the electromagnetic emissions have been generated from the ON/OFF of signals in the device. Recently, it becomes a topic of conversation on the information security that the ON/OFF on a desired signal in the device can be reproduced or guessed by receiving the electromagnetic emission. For an example, a display image on a personal computer (PC) can be reconstructed by receiving and analyzing the electromagnetic emission. In sum, this fact makes known information leakage due to electromagnetic emission. "TEMPEST" that has been known as a code name originated in the U.S. Department of Defense is to prevent the information leakage caused by electromagnetic emissions. This paper reports the brief summary of the information security due to electromagnetic emissions from information technology equipments.%パーソナルコンピュータ（PC：Personal Computer）や通信rn機器などの情報技術機器（IT機器：information technologyrnequipment）は，動作時に非意図的に微弱な電磁信号を放出rnする。この放出電磁信号は，IT機器内部で生成・伝送するrn多くのON/OFF信号から派生的に発生し，通常は「電磁雑rn音または無線妨害」として取り扱われる。