| 摘要 |
<p>A data content checker arrangement for protecting communication between a sensitive computer system (102) and an external computer system (104). The arrangement includes a store (108) connected to input and output sub-systems (106) and (114) and to content checkers (110) and (112) arranged in parallel. The input and output sub-systems (106) and (114) are connected to the external computer system (104) and the sensitive computer system (102) respectively. Data received from the external computer system (104) is encrypted by the input sub-system (106) using an encryption key to which the content checkers (110) and (112) have access. The content checkers (110) and (112) can therefore decrypt, read and check the data. If the data passes a content checker's checks, the checker digitally signs and stores it, decrypted, in the store (108); if the checks are not passed, the checker discards the data. The output sub-system (114) delivers data to the sensitive computer system (102) if the data has received both content checkers' digital signatures indicating acceptability.</p> |
