Protocol duplexer and protocol duplexing method

Abstract

A method of duplicating protocol for making identical the order of reception and contents of packets on the two computers of a duplicated computer system with respect to packets of specific types of communication. On the first computer, each packet taken in is checked to determine whether the packet is a packet of the specific types of communication before protocol processing. If the packet is a packet of the specific types of communication, the packet is passed to the protocol processing process and added to a virtual queue created in its shared memory. On the second computer, each packet taken in is checked to determine whether the packet is a packet of the specific types of communication before protocol processing. If the packet is a packet of the specific types of communication, the packet is discarded, and the one at the head of the virtual queue in its shared memory is passed to the protocol processing process.

1 .- 10 . (canceled)  
   
   
       11 . A protocol duplicating configuration for making identical an order of reception and contents of packets on first and second computers which are connected to a network, have shared memories forming a same address space, and make up a duplicated computer system for packets of specified communications, characterized by having on each of the first and second computers: 
 queue storing means for storing packets to be processed in order of being processed;    protocol processing means that is executed in response to reception of packets from the network;    temporary queue holding means for temporarily storing the packets having been processed by the protocol processing means in a queue; and    virtual queue storing means for storing packets of target communication for the protocol duplication in a queue.    
   
   
       12 . The protocol duplicating configuration of  claim 11 , 
 wherein the protocol processing means has packet taking-in means which takes in packets one by one from the queue storing means and determines whether each packet taken in is a packet of target communication for the protocol duplication, communication processing means for performing protocol processing on the packet, and packet output means for outputting the packet having been processed by the protocol processing means to the temporary queue storing means, and    the protocol processing means on the first computer takes in the packets stored in the queue storing means one by one by means of the packet taking-in means and determines whether each packet taken in is a packet of the specified communication, and if the packet is not a packet of the specified communication, performs the protocol processing on the packet by means of the communication processing means and outputs the packet to the temporary queue storing means by means of the packet output means.    
   
   
       13 . The protocol duplicating configuration of  claim 11 , 
 wherein the protocol processing means on the first computer takes in the packets stored in the queue storing means one by one by means of the packet taking-in means and determines whether each packet taken in is a packet of target communication for the protocol duplication, and if the packet is a target packet, performs the protocol processing on the packet by means of the communication processing means and in addition stores the packet in the virtual queue storing means.    
   
   
       14 . The protocol duplicating configuration of  claim 12 , 
 wherein the protocol processing means on the first computer takes in the packets stored in the queue storing means one by one by means of the packet taking-in means and determines whether each packet taken in is a packet of target communication for the protocol duplication, and if the packet is a target packet, performs the protocol processing on the packet by means of the communication processing means and in addition stores the packet in the virtual queue storing means.    
   
   
       15 . A method of duplicating protocol for making identical the order of reception and contents of packets on first and second computers which are connected to a network, have shared memories forming the same address space and make up a duplicated computer system for packets of specified communication, characterized by comprising steps executed on each computer: 
 storing packets received from said network in a queue in order of being processed;    executing protocol processing in response to the reception of packets from the network;    temporally storing packets having been subjected to the protocol processing in a temporary queue; and    storing packets of target communication for the protocol duplication in a virtual queue.    
   
   
       16 . The method of duplicating protocol of  claim 15 , wherein the protocol processing step comprises: 
 packet taking-in step which takes in packets one by one from the queue stored by the step of storing received packets in a queue and checks each packet taken in to determine whether the packet is a target packet for duplication;    communication processing step which performs the protocol processing on the packet; and    packet outputting step which outputs the packet from the communication processing step to the step of temporarily storing processed packets in a queue;    and takes in the packets one by one from the queue stored by the step of storing received packets in a queue and checks each packet taken in to determine whether the packet is a target packet for duplication by the packet taking-in step on the first computer, and    if the packet is not a target packet, performs the protocol processing on the packet by the communication processing step and outputs the packet to said step of temporarily storing processed packets in a queue by said packet outputting step.    
   
   
       17 . The method of duplicating protocol of  claim 15 , 
 characterized by, on the second computer, taking in packets one by one from the queue stored by the step of storing received packets in a queue and checking each packet to determine whether the packet is a target packet for duplication by the packet taking-in step on the second computer, and    if the packet is a target packet, comparing the packet with the packet at the head of the virtual queue, and only if both packets are identical, discarding the packet taken in and passing the packet at the head of the virtual queue to the communication processing means.