Patent ID: 6990204
Filing Date: 2006-01-24
Classification: H04L

Abstract:
1. An interface security system between devices connected to each other and transmitting/receiving a signal, the interface security system comprising: a first device transmitting/receiving a signal, the first device including: a first selector configured to select a connection pattern between the signal transmitted/received and a first external terminal configured to transmit/receive the signal based on a switch signal, the first selector including a first switch switching a connection between the signal and the first external terminal in accordance with the connection pattern selected by the first selector, and a first counter configured to generate counter values in synchronization between the first and second devices and to send the counter values to the second selector, the counter values being used for deciding a connection pattern; and a second device connected to said first device and configured to transmit/receive a signal, the second device including: a second selector configured to select a connection pattern between the signal transmitted/received and a second external terminal configured to transmit/receive the signal based on a switch signal, the second selector including a second switch configured to switch a connection between the signal and the second external terminal in accordance with the connection pattern selected by the second selector, and a second counter configured to generate counter values in synchronization between the first and second devices and to send the counter values to the first selector, the counter values being used for deciding a connection pattern; wherein the second selector inputs a switch signal of the same value as the switch signal that the first selector inputs, and the first and second selectors decide connection patterns, respectively, based on the counter values that the first and second counters generate.