Communication method and system that uses low latency/low data bandwidth and high latency/high data bandwidth pathways

Abstract

A communication system uses multiple communications links, preferably links that use different communications media. The multiple communications links may include a high latency/high bandwidth link using a fiber-optic cable configured to carry large volumes of data but having a high latency. The communications links may also include a low latency/low bandwidth link implemented using skywave propagation of radio waves and configured to carry smaller volumes of data with a lower latency across a substantial portion of the earth's surface. The two communications links may be used together to coordinate various activities such as the buying and selling of financial instruments.

1 . A method, comprising:
 transmitting command data from a transmission station via a first communication link, wherein the command data defines one or more commands;   transmitting triggering data from the transmission station via a second communication link, wherein the triggering data includes an identifier identifying at least one of the one or more commands;   wherein the second communication link transmits the triggering data using electromagnetic waves transmitted via skywave propagation; and   wherein the first communication link has greater latency than the second communication link.   
     
     
         2 . The method of  claim 1 , wherein the first communication link has larger data bandwidth than the second communication link. 
     
     
         3 . A method, comprising:
 transmitting command data from a transmission station via a first communication link, wherein the command data defines one or more commands;   transmitting triggering data from the transmission station via a second communication link, wherein the triggering data includes an identifier identifying at least one of the one or more commands; and   wherein the first and second communication links transmit the triggering data using electromagnetic waves transmitted via skywave propagation.   
     
     
         4 . The method of  claim 1 , further comprising:
 determining a maximum usable frequency for skywave propagation over the second communication link; and   transmitting the triggering data over the second communication link at a frequency that is less than or equal to the maximum usable frequency.   
     
     
         5 . The method of  claim 1 , further comprising:
 determining a minimum usable frequency for skywave propagation over the second communication link; and   transmitting the triggering data over the second communication link at a frequency that is greater than or equal to the minimum usable frequency.   
     
     
         6 . The method of  claim 1 , wherein said transmitting the triggering data includes transmitting the electromagnetic waves below the critical angle. 
     
     
         7 . The method of  claim 1 , further comprising:
 receiving the command data at a receiving station remote from the transmission station; and   receiving the triggering data at the receiving station.   
     
     
         8 . The method of  claim 7 , further comprising:
 transmitting the command data on both the first communication link and the second communication link.   
     
     
         9 . The method of  claim 8 , wherein said receiving the command data includes receiving the command data via the first communication link before receiving the command data via the second communication link. 
     
     
         10 . The method of  claim 8 , wherein said receiving the command data includes receiving the command data via the second communication link before receiving the command data via the first communication link. 
     
     
         11 . The method of  claim 7 , further comprising:
 transmitting the triggering data on both the first communication link and the second communication link.   
     
     
         12 . The method of  claim 11 , wherein said receiving the triggering data includes receiving the triggering data via the first communication link before receiving the triggering data via the second communication link. 
     
     
         13 . The method of  claim 11 , wherein said receiving the triggering data includes receiving the triggering data via the second communication link before receiving the triggering data via the first communication link. 
     
     
         14 . The method of  claim 7 , further comprising:
 executing at least one of the one or more commands identified in the triggering data in response to said receiving the triggering data, the at least one command executed using a processor at the receiving station.   
     
     
         15 . The method of  claim 14 , wherein said executing occurs on or after both the command data and triggering data is fully received at the receiving station. 
     
     
         16 . A method, comprising:
 receiving command data at a receiving station via a first communication link, wherein the command data defines one or more commands;   receiving triggering data at a receiving station via a second communication link, wherein the triggering data includes an identifier identifying at least one of the one or more commands;   wherein the triggering data passes over the second communication link to the receiving station using electromagnetic waves received via skywave propagation; and   wherein the command data passes over the first communication link to the receiving station without using skywave propagation.   
     
     
         17 . The method of  claim 16 , wherein the first communication link has larger data bandwidth than the second communication link. 
     
     
         18 . The method of  claim 16 , further comprising:
 executing at least one of the one or more commands identified in the triggering data in response to said receiving the triggering data, the at least one command executed using a processor at the receiving station.   
     
     
         19 . The method of  claim 1 , wherein the command data is defined by a collection of data with a first size, and the triggering data is defined by a collection of data with a second size, and the first size is greater than or equal to the second size. 
     
     
         20 . The method of  claim 1 , wherein the one or more commands include instructions to buy and/or sell one or more financial instruments. 
     
     
         21 . The method of  claim 1 , wherein the first communication link includes an optical fiber. 
     
     
         22 . The method of  claim 1 , further comprising:
 retransmitting the electromagnetic waves via one or more repeaters.   
     
     
         23 . The method of  claim 1 , wherein the second communication link transmits the triggering data using multiple frequencies. 
     
     
         24 . The method of  claim 23 , wherein:
 the second communication link transmits on a first frequency for a first period of time, and on a second frequency for the first period of time; and   the first frequency and the second frequency are different frequencies.   
     
     
         25 . The method of  claim 1 , wherein the skywave propagation includes refracting the electromagnetic waves from the ionosphere. 
     
     
         26 . The method of  claim 1 , wherein there is at least one skip zone between the transmitting and receiving stations. 
     
     
         27 . The method of  claim 1 , wherein the distance between the transmitting and receiving stations is greater than the radio horizon. 
     
     
         28 . The method of  claim 1 , wherein the first communication link, and the second communication link are the same communication link. 
     
     
         29 . The method of  claim 1 , wherein the first communication link, and the second communication link are separate communication links. 
     
     
         30 . A system, comprising:
 a processor coupled to a memory;   a first network interface responsive to the processor and coupled to a communication network, wherein the network interface is configured to send command data defining one or more commands using the communication network;   a second network interface responsive to the processor and coupled to a radio-frequency communication interface;   an antenna system coupled to the radio-frequency communications interface;   wherein the radio-frequency communication interface is configured to send triggering data using electromagnetic waves broadcast from the antenna system;   wherein the antenna system and radio-frequency interface are configured to transmit the electromagnetic waves via skywave propagation; and   wherein the triggering data includes an identifier identifying at least one of the one or more commands.