Universal serial bus (USB) extension

1. A method of communicating with a universal serial bus (USB) device connected to a host computer, the method comprising:

sending USB packets via an upstream mechanism to the USB device from the host computer;

at said upstream mechanism, maintaining a list of sent USB packets;

sending at least some spoofed responses from the upstream mechanism to the host computer;

waiting for actual responses from the USB device, and, while waiting for said actual responses from the USB device, in response to said host computer attempting to send another USB packet to said USB device via said upstream mechanism, said upstream mechanism sending said another USB packet to said USB device only if said another USB packet is not on the list of sent USB packets, otherwise said upstream mechanism (a) discarding said another USB packet, and (b) sending at least one other spoofed response to said host computer; and

providing at least some of the actual responses to the host computer.

2. A method as in claim 1 further comprising:

removing said USB packets from the list of sent USB packets.

3. A method of communicating with a universal serial bus (USB) device connected to a host computer, the method comprising, by an upstream mechanism:

obtaining a USB token from the host computer;

sending the USB token downstream towards the USB device;

sending at least one spoofed response to the host computer;

adding said USB token to a list of sent USB tokens;

waiting for an actual response from the USB device, and, while waiting for said actual response from the USB device, responsive to said host computer attempting to send a second USB token to said USB device via said upstream mechanism, sending said second USB token to said USB device only if said second USB token is not on the list of sent USB tokens, otherwise (a) discarding said second USB token, and (b) sending at least one other spoofed response to said host computer; and

providing the actual response to the host computer.

4. A method as in claim 3 wherein the token is selected from the group of tokens consisting of: OUT token, IN token, SOF, token, SETUP token and DATA token.

5. A method as in claim 3 wherein the spoofed response is

selected from the group of tokens consisting of an ACK token and a NAK token and known bad data.

6. A method as in claim 3 wherein the actual response is selected from the group of handshake tokens consisting of: ACK token; NAK token;

STALL token, and NYET token.

7. A method as in claim 3 wherein the USB token is an IN token and the at least one spoofed response is a NAK token.

8. A method as in claim 7 further comprising:

upon receipt of the actual response from downstream, sending an acknowledgement token to a downstream mechanism.

9. A method as in claim 3 wherein the USB token is a SETUP token and the at least one spoofed response is an ACK token.

10. A method as in claim 3 wherein the USB token is an OUT token and the at least one spoofed response is selected from the group of responses consisting of: a NAK token and known bad data.

11. A method as in claim 10 wherein the known bad data comprise data with a bad cyclic redundancy check (CRC).

12. A method as in claim 3 further comprising:

upon receipt of the actual response from downstream, storing the actual response and associating the actual response with the USB token, wherein said providing comprises:

providing the stored actual response.

13. A method as in claim 3 further comprising, by a downstream mechanism:

receiving a USB token from an upstream mechanism;

providing the USB token to the USB device;

obtaining an actual response from the USB device;

sending the actual response upstream;

storing a copy of the actual response, and

sending an acknowledgement token to the USB device.

14. A method as in claim 13 further comprising:

in response to an acknowledgement token from upstream, deleting the stored copy of the actual response.

15. A method as in claim 3 further comprising:

while waiting for the actual response, sending at least one other spoofed response to the host computer.

16. A method as in claim 3 further comprising:

upon receipt of the actual response from downstream, removing said USB token from the list of sent USB tokens.

17. A method of communicating with a universal serial bus (USB) device connected to a host computer, the method comprising:

by an upstream mechanism,

obtaining a USB token from the host computer;

sending the USB downstream towards the USB device;

adding said USB token to a list of sent USB tokens;

sending at least one spoofed response to the host computer;

waiting for an actual response from the USB device, and, while waiting for said actual response from the USB device, responsive to said host computer attempting to send a second USB token to said USB device via said upstream mechanism, said upstream mechanism sending said second USB token to said USB device only if said second USB token is not on the list of sent USB tokens, otherwise (a) discarding said second USB token, and (b) sending at least one other spoofed response to said host computer; and

providing the actual response to the host computer; and

by a downstream mechanism:

receiving the USB token from the upstream mechanism;

providing the USB token to the USB device;

obtaining a response from the USB device; and

sending the response from the USB device upstream as the actual response.

18. A method of communicating with a universal serial bus (USB) device connected to a host computer, the method comprising, by an upstream mechanism:

obtaining a USB OUT token from the host computer;

sending the USB OUT token downstream;

adding said USB OUT token to a list of sent USB tokens;

sending a spoofed response to the host computer;

obtaining a USB DATA token from the host computer;

sending the USB DATA token downstream;

adding said USB DATA token to a list of sent USB tokens;

waiting for an actual response from the USB device, and, while waiting for said actual response from the USB device, responsive to said host computer attempting to resend said USB OUT token and said USB DATA token to said USB device via said upstream mechanism, said upstream mechanism sending said USB OUT token and said USB DATA token to said USB device only if said USB OUT token and said USB DATA token are not on the list of sent USB tokens, otherwise (a) discarding said USB OUT token and said USB DATA token, and (b) sending at least one other spoofed response to said host computer; and

providing the actual response to the host computer.

19. A universal serial bus (USB) connector system comprising:

(A) an upstream mechanism connectable to a USB port of a host computer;

(B) a downstream mechanism connectable to at least one USB device; and

(C) a connection link connecting the upstream and downstream mechanisms, wherein

the upstream mechanism is constructed and adapted to:

(a) obtain a USB token from a host computer connected to the upstream mechanism;

(b) send the USB downstream towards downstream mechanism and add said USB token to a list of sent USB tokens;

(c) send at least one spoofed response to the host computer;

(d) wait for an actual response from the USB device, and, while waiting for said actual response from the USB device, responsive to said host computer attempting to send a second USB token to said USB device via said upstream mechanism, to send said second USB token to said USB device only if said second USB token is not on the list of sent USB tokens, otherwise to (i) discard said second USB token, and (ii) send at least one other spoofed response to said host computer; and

(e) provide the actual response to the host computer.

20. A USB connector system as in claim 19 wherein the downstream mechanism is constructed and adapted to:

receive a USB token from an upstream mechanism;

provide the USB token to a USB device connected to the downstream mechanism;

obtain an actual response from the USB device;

send the actual response upstream; and

send an acknowledgement token to the USB device.

21. A USB connector system as in claim 19 wherein the connection link comprises a fiber cable connected to the upstream mechanism by an upstream transceiver and to the downstream mechanism by a downstream transceiver.

22. A USB connector system as in claim 19 wherein the cable is between 100 meters and 750 meters long.

23. A USB connector system as in claim 19 wherein the upstream mechanism the downstream mechanism and the connection link are packaged in a single cable.

24. A universal serial bus (USB) connector system as in claim 19 wherein the connection link comprises a cable exceeding 300 meters in length.