Heat exchanger

Abstract

A heat exchanger with louvers twisted by a predetermined angle with respect to flat parts of fins and with louver passages formed between adjoining louvers, wherein step differences projecting out to the louver passage side are provided at the louvers. According to this, when cooling air flows through the louver passages, the flow of the cooling air is disrupted by the step differences and temperature boundary layers are destroyed, so the local heat conductivity is again raised at the locations of the step differences.

1 . A computer-implemented method for communication within a network, said method comprising the steps of: 
 transmitting a data packet as a broadcast signal from a first application node of a first subnetwork to a first gateway node of the first subnetwork;    transmitting the data packet as a point-to-point signal from the first gateway node to a second gateway node of a second subnetwork;    transmitting the data packet as a broadcast signal from the second gateway node of the second subnetwork to at least one application node of the second subnetwork; and    simulating war games between two remote geographic sites.    
   
   
       2 . The computer-implemented method as set forth in  claim 1  further comprising the steps of: 
 transmitting another data packet as a broadcast signal from the at least one application node of the second subnetwork to the second gateway node of the second subnetwork;    transmitting the other data packet as a point-to-point signal from the second gateway node to the first gateway node of the first subnetwork; and    transmitting the data packet as a broadcast signal from the first gateway node of the first subnetwork to the first application node of the first subnetwork.    
   
   
       3 . The computer-implemented method as set forth in  claim 1  wherein said transmitting the data packet as a point-to-point signal is conducted across an undedicated communication network.  
   
   
       4 . The computer-implemented method as set forth in  claim 3  wherein the undedicated communication network is the Internet.  
   
   
       5 . (canceled)  
   
   
       6 . The computer-implemented method as set forth in  claim 1  wherein the broadcast signals each comprise an Ethernet Protocol Data Unit.  
   
   
       7 . The computer-implemented method as set forth in  claim 1  wherein the point-to-point signal includes an IP address.  
   
   
       8 . The computer-implemented method as set forth in  claim 1  further including the step of transmitting the data packet as a broadcast signal to a second application node of the first subnetwork.  
   
   
       9 . A system comprising: 
 a first device for transmitting a data packet as a broadcast signal from a first application node of a first subnetwork to a first gateway node of the first subnetwork;    a second device for transmitting the data packet as a point-to-point signal from the first gateway node to a second gateway node of a second subnetwork; and    a third device for transmitting the data packet as a broadcast signal from the second gateway node of the second subnetwork to at least one application node of the second subnetwork,    the broadcast signals each comprising an Ethernet Protocol Data Unit.    
   
   
       10 . The system as set forth in  claim 9  wherein said third device transmits another data packet as a broadcast signal from the at least one application node of the second subnetwork to the second gateway node of the second subnetwork; said second device transmits the. other data packet as a point-to-point signal from the second gateway node to the first gateway node of the first subnetwork; and said third device transmits the data packet as a broadcast signal from the first gateway node of the first subnetwork to the first application node of the first subnetwork.  
   
   
       11 . The system as set forth in  claim 9  wherein said first device is a computer.  
   
   
       12 . The system as set forth in  claim 11  wherein the first gateway node converts the data packet from the broadcast signal to the point-to-point signal by adding an IP address to the broadcast signal.  
   
   
       13 . The system as set forth in  claim 9  wherein said third means is a computer.  
   
   
       14 . The system as set forth in  claim 9  wherein said second means is an undedicated intranet.  
   
   
       15 . The system as set forth in  claim 9  wherein said first device transmits the data packet as a broadcast signal form the first application node to a second application node of the first subnetwork.  
   
   
       16 . An apparatus for simulating a war game, said apparatus comprising: 
 a first means for transmitting a data packet as a broadcast signal from a first application node of a first subnetwork to a first gateway node of the first subnetwork;    a second means for transmitting the data packet as .a point-to-point signal from the first gateway node to a second gateway node of a second subnetwork; and    a third means for transmitting the data packet as a broadcast signal from the second gateway node of the second subnetwork to at least one application node of the second subnetwork,    said first, second, and third transmitting means simulating the war game between two remote geographic sites.    
   
   
       17 . The apparatus as set forth in  claim 16  wherein said third means transmits another data packet as a broadcast signal from the at least one application node of the second subnetwork to the second gateway node of the second subnetwork; said second means transmits the other data packet as a point-to-point signal from the second gateway node to the first gateway node of the first subnetwork; and said third means transmits the data packet as a broadcast signal from the first gateway node of the first subnetwork to the first application node of the first subnetwork.  
   
   
       18 . A computer program product containing executable instructions for communicating within a network, said product comprising: 
 a first subnetwork having a first application node and a first gateway node; and    a second subnetwork having a second application node and a second gateway node,    said first application node transmitting a data packet as a broadcast signal to said first gateway node of said first subnetwork;    said first gateway node transmitting said data packet as a point-to-point signal from said first gateway node to said second gateway node of said second subnetwork,    said second gateway node transmitting said data packet as a broadcast signal from said second gateway node of said second subnetwork to said second application node of said second subnetwork,    the broadcast signals each comprising an Ethernet Protocol Data Unit.    
   
   
       19 . The computer program product as set forth in  claim 18  wherein said second application node transmits another data packet as a broadcast,signal to said second gateway node, said second gateway node transmits said other data packet as a point-to-point signal to said first gateway node, and said first gateway node transmits said other data packet as a broadcast signal to said first and second application nodes.  
   
   
       20 . The computer program product as set forth in  claim 18  wherein said first application node transmits said data packet as a broadcast signal to another application node of said first subnetwork simultaneously to the transmission of said data packet to said first gateway node.