Session-based sequence checking

Abstract

A device may include logic configured to receive a data unit intended for a destination device and to obtain information from the data unit. The logic may be configured to identify a window using the obtained information, where the window has a range determined by a lower boundary and an upper boundary. The logic may be configured to forward the data unit to the destination device when a portion of the data unit information is within the window.

1 - 24 . (canceled) 
     
     
         25 . A method, performed by a device, the method comprising:
 receiving, at a processor of the device, a data unit on behalf of a destination device;   obtaining, by the processor, information associated with the data unit, the destination device, or a source device;   establishing, by the processor, a lower boundary using the obtained information and an upper boundary using the obtained information, where the lower boundary is not equal to the upper boundary;   determining, by the processor and on behalf of the destination device, whether information associated with the data unit is within the lower boundary and the upper boundary; and   forwarding, by the processor, the data unit to the destination device when the information associated with the data unit is within the lower boundary and the upper boundary.   
     
     
         26 . The method of  claim 25 , further comprising:
 storing the information associated with the data unit, the destination device, or a source device in a session table.   
     
     
         27 . The method of  claim 25 , where the information associated with the data unit includes a sequence number of the data unit. 
     
     
         28 . The method of  claim 25 , further comprising:
 determining whether second information associated with the data unit is below a threshold, and   where forwarding the data unit to the destination device comprises:
 forwarding the data unit to the destination device when the information associated with the data unit is within the lower boundary and the upper boundary and when the second information is below the threshold. 
   
     
     
         29 . The method of  claim 25 , further comprising:
 dropping the data unit when the information associated with the data unit is not within the lower boundary and the upper boundary.   
     
     
         30 . The method of  claim 25 , further comprising:
 maintaining a data structure on behalf of the source device or the destination device, where the data structure includes information used to determine whether the data unit should be forwarded to the destination.   
     
     
         31 . The method of  claim 25 , further comprising:
 maintaining a session table on behalf of the destination device or the source device, where the session table includes information associated with a communication session between the source device and the destination device.   
     
     
         32 . A device, comprising:
 logic to:
 receive a data unit intended for a destination device, 
 obtain information from the data unit, 
 identify a window using the obtained information, where the window has a range determined by a lower boundary and an upper boundary, and 
 forward the data unit to the destination device when a portion of the data unit information is within the window. 
   
     
     
         33 . The device of  claim 32 , where the logic is further to:
 drop the data unit when the portion of the data unit is not within the window.   
     
     
         34 . The device of  claim 32 , where the logic is further to:
 determine whether second information associated with the data unit is below a threshold, and   where, when forwarding the data unit to the destination device, the logic is further to:
 forward the data unit to the destination device when the information associated with the data unit is within the lower boundary and the upper boundary and when the second information is below the threshold. 
   
     
     
         35 . The device of  claim 34 , where the logic is further to:
 drop the data unit when the second information associated with the data unit is not below a threshold.   
     
     
         36 . The device of  claim 32 , where, when identifying a window, the logic is further to:
 identify the window using information associated with a source device or the destination device.   
     
     
         37 . The device of  claim 32 , where the portion of the data unit includes a sequence number. 
     
     
         38 . The device of  claim 32 , where the device further comprises a session table to store information associated with a communication session between a source device and the destination device. 
     
     
         39 . The device of  claim 38 , where the logic is further to:
 store the obtained information in the session table.   
     
     
         40 . A device, comprising:
 a session table; and   logic to:
 establish a lower limit using information from the session table and information from a data unit, 
 establish an upper limit using information from the session table and the information from the data unit, 
 determine whether a sequence number for the data unit is between the lower limit and the upper limit, and 
 forward the data unit to a destination when the sequence number is between the lower limit and the upper limit. 
   
     
     
         41 . The device of  claim 40 , where the logic is further to:
 drop the data unit when the sequence number is not between the lower limit and the upper limit.   
     
     
         42 . The device of  claim 40 , where the logic is further to:
 determine whether an acknowledgement number for the data unit is below a threshold, and   where, when forwarding the data unit, the logic is further to:
 forward the data unit to the destination when the sequence number is between the lower limit and the upper limit and the acknowledgement number for the data unit is below the threshold. 
   
     
     
         43 . The device of  claim 42 , where the logic is further to:
 drop the data unit when the acknowledgement number for the data unit is not below the threshold.   
     
     
         44 . The device of  claim 40 , where the logic is further to:
 store the information from the data unit in the session table.