# US 5,703,562 A · Method for transferring data from an unsecured computer to a secured computer

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 5,703,562 A
- Document ID: US5703562A
- Status: Granted
- Kind: A
- Application number: 08/753,130
- Filed: 1996-11-20
- Granted: 1997-12-30
- Earliest claimed: 1996-11-20
- Assignees: Sandia Corporation
- Inventors: Curt A. Nilsen
- Web page: https://patentgrep.com/patent/US5703562A

## CPC

- H04L 63/105: {Multiple levels of security}
- G06F 11/1625: {in communications, e.g. transmission, interfaces}
- H04L 63/12: {Applying verification of the received information (cryptographic mechanisms or cryptographic arrangements for data integrity or data verification H04L9/32)}
- H04L 69/324: in the data link layer [OSI layer 2], e.g. HDLC
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)
- G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N)

## Abstract

A method is described for transferring data from an unsecured computer to a secured computer. The method includes transmitting the data and then receiving the data. Next, the data is retransmitted and rereceived. Then, it is determined if errors were introduced when the data was transmitted by the unsecured computer or received by the secured computer. Similarly, it is determined if errors were introduced when the data was retransmitted by the unsecured computer or rereceived by the secured computer. A warning signal is emitted from a warning device coupled to the secured computer if (i) an error was introduced when the data was transmitted or received, and (ii) an error was introduced when the data was retransmitted or rereceived.

## Claims

### Claim 1

A method for transferring data from an unsecured computer to a secured computer, the method comprising:
(a) transmitting the data;
(b) receiving the data;
(c) retransmitting the data;
(d) rereceiving the data;
(e) determining if an error was introduced when the data was transmitted by the unsecured computer or received by the secured computer;
(f) determining if an error was introduced when the data was retransmitted by the unsecured computer or rereceived by the secured computer; and
(g) emitting an warning signal from a warning device coupled to the secured computer if:
(i) an error was introduced when the data was transmitted or received, and
(ii) an error was introduced when the data was retransmitted or rereceived.

### Claim 2 (depends on 1)

The method of claim 1 further comprising:
(h) storing the received data on a storage device coupled to the secured computer if an error was not introduced when the data was transmitted or received.

### Claim 3 (depends on 1)

The method of claim 1 further comprising:
(h) storing the rereceived data on a storage device coupled to the secured computer if an error was not introduced when the data was retransmitted or rereceived.

### Claim 4 (depends on 1)

The method of claim 1, wherein the data is transmitted and retransmitted optically.

### Claim 5 (depends on 1)

The method of claim 1, wherein the data is transmitted and retransmitted by an IR LED.

### Claim 6 (depends on 1)

The method of claim 1, wherein the data is transmitted and retransmitted by a LASER.

### Claim 7 (depends on 1)

The method of claim 1, further comprising:
(h) if an error was not introduced when either (i) the data was transmitted and received or (ii) when the data was retransmitted and rereceived, then emitting an audible signal.

### Claim 8 (depends on 1)

The method of claim 1, further comprising:
(g) transmitting a traffic summary to the secured computer.

### Claim 9 (depends on 1)

The method of claim 1, further comprising:
(g) transmitting a traffic summary to the secured computer at predetermined intervals.

### Claim 10

A secure transfer system comprising:
(a) an unsecured computer;
(b) a transmitter operatively coupled to the unsecured computer, the transmitter for transmitting and retransmitting data from the unsecured computer;
(c) a receiver for receiving data transmitted from the transmitter and for rereceiving data retransmitted from the transmitter; and
(d) a secured computer operatively coupled to the receiver, the secured computer having a warning device for emitting a warning signal if (i) an error was introduced when the data was transmitted or received and (2) an error was introduced when the data was retransmitted or rereceived.

### Claim 11 (depends on 10)

The secure transfer system of claim 10, wherein the transmitter is an optical transmitter.

### Claim 12 (depends on 10)

The secure transfer system of claim 10, wherein the transmitter includes an IR LED.

### Claim 13 (depends on 10)

The secure transfer system of claim 10, wherein the transmitter includes a LASER.

### Claim 14 (depends on 10)

The secure transfer system of claim 10, wherein the warning device is an audible warning device.

### Claim 15 (depends on 10)

The secure transfer system of claim 10, wherein the warning device is a speaker.