Transmission protocol controller

Patent metadata

Field	Value
Publication number	US-9231697-B2
Application number	US-201314132868-A
Country	US
Kind code	B2
Filing date	Dec 18, 2013
Priority date	Dec 18, 2013
Publication date	Jan 5, 2016
Grant date	Jan 5, 2016

Abstract

A free-space optical (FSO) transceiver can include a transmission protocol configured to encapsulate outgoing network packets in by employing a reliable ordered protocol that relies on retransmission of lost data to form outgoing encapsulated packets. The transmission protocol controller can be configured to employ a congestion algorithm that optimizes throughput over a lossy link. The FSO transceiver can also include a transmitter configured to provide an output optical signal corresponding to the outgoing encapsulated packets over an FSO link.

First claim

What is claimed is:

1. A free-space optical (FSO) transceiver comprising:
a transmission protocol controller configured to encapsulate outgoing Ethernet frames by employing the Transmission Control Protocol (TCP) to form outgoing TCP-encapsulated packets, wherein the protocol controller is configured to employ a congestion algorithm that optimizes throughput over a lossy link, wherein the outgoing Ethernet frames encapsulate TCP packets, such that each of the outgoing TCP-encapsulated packets generated by the transmission protocol controller encapsulates one of the outgoing Ethernet frames that encapsulates another TCP packet; and
a transmitter configured to provide an output optical signal corresponding to the outgoing TCP-encapsulated packets over a FSO link.

2. The FSO transceiver of claim 1 , wherein the congestion algorithm is the transmission control protocol (TCP) Westwood+ algorithm.

3. The FSO transceiver of claim 1 , wherein the FSO link is subject to atmospheric scintillation.

4. The FSO transceiver of claim 1 , further comprising:
a receiver configured to receive an input optical signal via the FSO link, wherein the input optical signal includes incoming TCP-encapsulated packets;
wherein the protocol controller is further configured to unencapsulate the incoming TCP-encapsulated packets to form incoming network packets.

5. The FSO transceiver of claim 4 , further comprising:
a network port coupled to a local area network (LAN), the network port being configured to:
receive the outgoing Ethernet frames from the LAN; and
provide the incoming network packets to the LAN.

6. The FSO transceiver of claim 5 , wherein the network port is an Ethernet port and the incoming network packets are incoming Ethernet frames.

7. The FSO transceiver of claim 5 , wherein the incoming Ethernet frames encapsulate transmission control protocol (TCP) packets.

8. The FSO transceiver of claim 5 , further comprising a buffer configured to add latency to each of the incoming network packets.

9. The FSO transceiver of claim 1 , wherein the output optical signal is transmitted to another FSO transceiver via the FSO link.

10. A system comprising:
a first free space optical (FSO) transceiver configured to:
receive Ethernet frames from a first subnet of a local area network (LAN);
encapsulate the Ethernet frames in Transmission Control Protocol (TCP)-encapsulated packets by employing the TCP with a congestion algorithm that optimizes throughput over a lossy link, wherein the Ethernet frames encapsulate TCP packets, such that each of the TCP-encapsulated packets encapsulates one of the Ethernet frames that encapsulates another TCP packet; and
provide an output optical signal over free space, the output optical signal corresponding to the encapsulated packets; and

a second FSO transceiver separated by free space from the FSO transceiver, the second FSO transceiver being configured to:
receive the output optical signal from the first FSO transceiver;
unencapsulate the TCP-encapsulated packets to reconstruct the Ethernet frames; and
provide the Ethernet frames to a second subnet of the LAN.

11. The system of claim 10 , wherein the second FSO transceiver is configured to add a latency to each of the Ethernet frames provided to the second subnet of the LAN.

12. The system of claim 10 , wherein the Ethernet frames are provided from a first node on the first subnet of the LAN to a second node on the second subnet of the LAN.

13. The system of claim 10 , wherein the first FSO transceiver and the second FSO transceiver are separated by at least 1 kilometer.

14. A method comprising:
receiving, by a network port, Ethernet frames;
encapsulating, by a protocol controller, the network packets with the transmission control protocol (TCP) to form TCP-encapsulated packets, wherein the TCP-encapsulated packets are formed with a congestion algorithm that optimizes throughput over a lossy link, wherein the Ethernet frames encapsulate TCP packets, such that each of the TCP-encapsulated packets generated by the protocol controller encapsulates one of the Ethernet frames that encapsulates another TCP packet; and
transmitting, by a transmitter, an output optical signal over free space that is based on the TCP-encapsulated packets.

15. The method of claim 14 , wherein the congestion algorithm is the TCP Westwood+ congestion algorithm.

16. The method of claim 15 , wherein the output optical signal is received by a receiver separated from the transmitter by a distance of at least 500 meters.

17. The FSO transceiver of claim 1 , wherein the TCP packets encapsulated by the outgoing Ethernet frames and the outgoing TCP-encapsulated packets implement different congestion algorithms.

Assignees

• Archer Christopher A
• Cicchiello James M
• Featherston John
• Bean Frederick D
• Northrop Grumman Systems Corp

Inventors

• Archer Christopher A
• Cicchiello James M
• Featherston John
• Bean Frederick D

Classifications

• H04B10/40

  Transceivers · CPC title

• H04B10/11 Primary

  Arrangements specific to free-space transmission, i.e. transmission through air or vacuum · CPC title

• H04B10/1149

  Arrangements for indoor wireless networking of information · CPC title

• H04B10/1129 Primary

  Arrangements for outdoor wireless networking of information · CPC title