Method and apparatus for time synchronization in a network data processing system

Abstract

A method, apparatus, and computer implemented instructions for synchronizing time in a network data processing system. A request for time synchronization is received at a target data processing system. A current target time at the target data processing system is placed in a reply. The reply is sent to the source data processing system. A current source time from when the reply is received at the source data processing system is compared to the current target time to generate a comparison. A synchronization factor is generated using the comparison.

1 - 5 . (canceled)  
     
     
         6 . A method in a data processing system for synchronizing time, the method comprising: 
 sending a synchronization request to a target system;    receiving a reply, wherein the reply includes a current time from the target system;    identifying a clock skew using the current time from the target system; and    generating a time stamp for an authentication request including a set of user credentials using the clock skew for an authentication process which validates the authentication request wherein the set of user credentials is valid for a predetermined period of time.    
     
     
         7 . The method of  claim 6  further comprising: 
 sending the message to a server on which the authentication process is resident.    
     
     
         8 . The method of  claim 6 , wherein the reply which includes the current time from the target system is encrypted so that the authenticity of the reply can be verified.  
     
     
         9 . The method of  claim 6 , wherein the target system is a key distribution center server.  
     
     
         10 - 11 . (canceled)  
     
     
         12 . The method of  claim 7  further comprising: 
 determining whether the server is located in a different realm from the target system, prior to sending the message to the server; and    responsive to the server being located in the different realm, sending a synchronization request to a new target system in the different realm;    receiving a reply, wherein the reply includes a new current time from the new target system;    identifying a new clock skew using the current time from the new target system; and    generating a new time stamp for the message using the new clock skew.    
     
     
         13 . The method of  claim 12 , wherein the new target system is a key distribution center server.  
     
     
         14 . A data processing system comprising: 
 a bus system;    a communications unit connected to the bus, wherein data is sent and received using the communications unit;    a memory connected to the bus system, wherein a set of instructions are located in the memory; and    a processor unit connected to the bus system, wherein the processor unit executes the set of instructions to send a synchronization request to a target system; receive a reply, wherein the reply includes a current time from the target system; identify a clock skew using the current time from the target system; and generate a time stamp for an authentication message including a set of user credentials using the clock skew, wherein the user credentials are valid for a predetermined period of time.    
     
     
         15 . The data processing system of  claim 14 , wherein the bus system includes a primary bus and a secondary bus.  
     
     
         16 . The data processing system of  claim 14 , wherein the processor unit includes a single processor.  
     
     
         17 . The data processing system of  claim 14 , wherein the processor unit includes a plurality of processors.  
     
     
         18 . The data processing system of  claim 14 , wherein the communications unit is an Ethernet adapter.  
     
     
         19 - 33 . (canceled)  
     
     
         34 . A computer program product in a computer readable medium for synchronizing time, the computer program product comprising: 
 first instructions for sending a synchronization request to a target system;    second instructions for receiving a reply, wherein the reply includes a current time from the target system;    third instructions for identifying a clock skew using the current time from the target system; and    fourth instructions for generating a time stamp for an authentication request including a set of user credentials using the clock skew for an authentication process which validates the authentication request wherein the set of user credentials is valid for a predetermined period of time.    
     
     
         35 . The computer program product of  claim 34  further comprising: 
 fifth instructions for sending the message to a server on which the authentication process is resident.    
     
     
         36 . The computer program product of  claim 34 , wherein the second instructions for receiving a reply which includes the current time from the target system is encrypted so that the authenticity of the reply can be verified.  
     
     
         37 . The computer program product of  claim 34 , wherein the target system is a key distribution center server.  
     
     
         38 . The data processing system of  claim 14 , wherein the processor unit further executes the set of instructions to send the message to a server on which the authentication process is resident.  
     
     
         39 . The data processing system of  claim 14 , wherein the reply which includes the current time from the target system is encrypted so that the authenticity of the reply can be verified.  
     
     
         40 . The data processing system of  claim 14 , wherein the target system is a key distribution center server.  
     
     
         41 . The data processing system of  claim 38 , wherein the processor unit further executes the set of instructions to determine whether the server is located in a different realm from the target system, prior to sending the message to the server; and, in response to the server being located in the different realm, send a synchronization request to a new target in the different realm; receive a reply, wherein the reply includes a new current time from the new target; identify a new clock skew using the current time from the new target; and generate a new time stamp for the message using the new clock skew.  
     
     
         42 . The data processing system of  claim 41 , wherein the new target system is a key distribution center server.