Abstract:
An auditing system is disclosed comprising a Policy Validation Mechanism Program (PVMP) that operates in conjunction with a Workflow Engine (WE), and a Policy Validation Server Program (PVSP) that operates on a Policy Validation Server (PVS) connected to the WE by a secure communication link. The PVMP converts a workflow to a workflow representation (WR) and sends the WR to the PVS. The PVSP compares the steps in the WR to a security policy identified for that WR and determines whether the WR is in compliance. In addition, the PVSP validates a checksum for the WR and logs the checksum for subsequent comparisons. The PVSP uses the checksum to determine whether a policy has changed during execution of the workflow. If the WR is not in compliance, if the checksum cannot be validated, or if a policy has changed, then a failure notification is sent to the WE. Otherwise, a success notification is sent to the WR.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation application of co-pending U.S. utility patent application entitled “Policy Based Auditing of Workflows” filed on Apr. 19, 2005 and accorded Ser. No. 11/109,087, and claims priority therefrom. 
    
    
     FIELD OF THE INVENTION 
     The present invention is directed to multi computer data transferring and computer network monitoring in general, and to auditing of workflows over a network in particular. 
     BACKGROUND OF THE INVENTION 
     As used herein, workflow means the organization of processes into a well-defined flow of operations to fulfill a business need. A process means a defined series of tasks to be completed in stages where data is forwarded to an appropriate member of a workgroup for each task resulting in a final workflow data. As used herein workgroup means a plurality of users, each having a computer connected to one or more other users within the group by a network, and where the plurality of users communicate through the network to accomplish a defined series of tasks to produce a final workflow product. 
     Workflow products need a mechanism to enforce a policy on a given workflow in order to ensure that the workflow consistently complies with a given standard or expectation. One example of this would be a workflow that violates organizational security policies by using credentials (user id/pass) to login to a target server instead of Secure Sockets Layer (SSL) certificates. Another example is the Global Solutions Directory (GSD) Universal Management Infrastructure (UMI) requirement to audit workflows based on a particular security policy or set of rules for items such as error handling and best coding practices. Other examples include validation of workflows based on execution of error handling, best coding or implementation practices. 
     Policy in workflow typically exists around what one can do to a resource within the workflow, but not to the workflow itself. The majority of current solutions manually inspect the workflows prior to making them available to the workflow engine for execution. There is, at present, no capability to automatically ensure policy enforcement immediately prior, during and at completion of a workflow execution. 
     Carlos Ribeiro and Paulo Guedes of IST/INESC Portugal, in “Verifying Workflow Processes against Organization Security Policies,” disclose “a static analyzer that automatically verifies the consistency between workflow specification written in WPDL (Workflow Process Definition Language) and organization security policies . . . . ” Specifically, the authors seek to show how an SPL (security language) specification can be checked against a WPDL workflow specification. (see http://www.inesc-id.pt/pt/inidadores/Ficheiros/1164.pdf). Douglas Long, Julie Baker, and Francis Fung of Odyssey Research Associates, in “A Prototype Secure Workflow Server” disclose their prototype policy editor, workflow server, and underlying Java-based implementation for workflow policies that provide “fine grained dynamic access and control.” (see http://www.atc-nycorp.com/papers/LONG_ACSAC_SecureWorkflow.pdf). The IBM Tivoli Access Manager for Business Integration provides, inter alia, centralized administration of both access control and data protection services across mainframe and distributed servers. (see http://www-306.ibm.com/software/tivoli/products/access-mgr-bus-integration). 
     The above solutions focus on policy driven secured access to the resources within a workflow at the time of access. Moreover, these solutions focus on security, but do not address elimination of some or all manual inspection of workflows for compliance with business policies (such as, but not limited to, error handling, best coding or implementation practice policies). Moreover, these solutions cannot verify that the workflow itself is free from tampering at any given point in execution. What is needed is a system and method to process workflows of varying formats and standards for compliance with security and business policies. What is further needed is a mechanism to provide warnings during the processing of the workflow so that remedial action can be completed as a prerequisite to validation of the workflow. 
     SUMMARY OF THE INVENTION 
     The invention that meets the needs described above is an auditing system comprising a Policy Validation Mechanism Program (PVMP) that operates in conjunction with a Workflow Engine (WE), and a Policy Validation Server Program (PVSP) that operates on a Policy Validation Server (PVS) connected to the WE by a secure communication link. The PVMP converts a workflow to a workflow representation (WR) and sends the WR to the PVS. The PVSP compares the steps in the WR to a security policy identified for that WR and determines whether the WR is in compliance. In addition, the PVSP validates a checksum for the WR and logs the checksum for subsequent comparisons. The PVSP uses the checksum to determine whether a policy has changed during execution of the workflow. If the WR is not in compliance, if the checksum cannot be validated, or if a policy has changed, then a failure notification is sent to the WE. Otherwise, a success notification is sent to the WR. In an embodiment with Warning Management (WM), in the event of a failure, a warning report is sent so that if approval workflows are completed and returned, a response may be changed to success. The PVMP sends the WR to the PVS at random intervals. Upon receipt of a failure notification, the PVMP suspends the workflow until corrective action can be completed, the corrected workflow converted to a WR, and the WR sent to the PVS. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will be understood best by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is an illustration of a computer network used to implement the present invention; 
         FIG. 2A  is an illustration of the memory or storage of the Workflow Engine and the Policy Validation Mechanism Program (PVMP); 
         FIG. 2B  is an illustration of the memory or storage of the Policy Validation Server containing the Policy Validation Server Program (PVSP); 
         FIG. 2C  is an overview of the processing of a Workflow Representation (WR); 
         FIG. 3  is an illustration of the logic of the Policy Validation Server Process (PVSP); and 
         FIG. 4  is an illustration of the logic of the Policy Validation Mechanism Program (PVMP). 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The principles of the present invention are applicable to a variety of computer hardware and software configurations. The term “computer hardware” or “hardware,” as used herein, refers to any machine or apparatus that is capable of accepting, performing logic operations on, storing, or displaying data, and includes without limitation processors and memory; the term “computer software” or “software,” refers to any set of instructions operable to cause computer hardware to perform an operation. A “computer,” as that term is used herein, includes without limitation any useful combination of hardware and software, and a “computer program” or “program” includes without limitation any software operable to cause computer hardware to accept, perform logic operations on, store, or display data. A computer program may, and often is, comprised of a plurality of smaller programming units, including without limitation subroutines, modules, functions, methods, and procedures. Thus, the functions of the present invention may be distributed among a plurality of computers and computer programs. The invention is described best, though, as a set of computer programs that configure and enable a client computer and a server computer to implement the novel aspects of the invention. For illustrative purposes, the inventive computer programs will be referred to as the Policy Validation Mechanism Program (PVMP) and the Policy Validation Server Program (PVSP). 
     As used herein, checksum means a calculation performed using a formula to determine a second numerical value for an electronic message where the message contains a first numerical value that was calculated using the formula before the message was sent (so that, upon receipt, if the first and second numerical values are different, the message is known to have been changed in transit). As used herein, Final Workflow Data File (FWDF) means a data file that contains the results of the completion of the defined tasks in a workflow by a workgroup. As used herein, Policy Validation Mechanism (PVM) means a program within or interacting with the Workflow Engine that sends the Workflow Representation to the Policy Validation Server. As used herein Policy Validation Server Program (PVSP) means a program residing and operating on a policy validation server that receives a workflow representation and issues a success or failure notification. As used herein, Resource means any software or hardware available to a workgroup for use in creating a final workflow data file, but does not include the Policy Validation Server Program, or any other program residing or operating on the Policy Validation Server. As used herein, Workflow Engine (WE) means the resources available to the workgroup for a particular workflow. As used herein, Workflow Representation (WR) means a particular format to which all workflows are converted prior to transmission to the Policy Validation Server (for example, if the workflow was WebSphere Process Choreographer Flow Definition Markup Language based, and if the particular format was an open standard such as Business Process Execution Language (BPEL), then the workflow would be converted to BPEL). 
     Additionally, the auditing system is described below with reference to an exemplary network of hardware devices, as depicted in  FIG. 1 . A “network” comprises any number of hardware devices coupled to and in communication with each other through a communications medium, such as the Internet. A “communications medium” includes without limitation any physical, optical, electromagnetic, or other medium through which hardware or software can transmit data. For descriptive purposes, exemplary network  100  has only a limited number of nodes, including workstation computer  105 , workstation computer  110 , server computer  115 , and persistent storage  120 . Network connection  125  comprises all hardware, software, and communications media necessary to enable communication between network nodes  105 - 120 . Unless otherwise indicated in context below, all network nodes use publicly available protocols or messaging services to communicate with each other through network connection  125 . 
     Policy Validation Mechanism Program (PVMP)  300  typically is stored in a memory, represented schematically as memory  200  in  FIG. 2A . The term “memory,” as used herein, includes without limitation any volatile or persistent medium, such as an electrical circuit, magnetic disk, or optical disk, in which a computer can store data or software for any duration. A single memory may encompass and be distributed across a plurality of media. Thus,  FIG. 2  is included merely as a descriptive expedient and does not necessarily reflect any particular physical embodiment of memory  220 . As depicted in  FIG. 2A , though, memory  200  includes additional data and programs. Of particular import to Policy Validation Mechanism Program (PVMP)  300 , memory  200  includes Workflow Engine ( 210 ) and Workflow Representation files  220  with which PVMP  300  interacts. 
     Policy Validation Mechanism Program (PVMP)  300  typically is stored in a memory, represented schematically as memory  200  in  FIG. 2A . Policy Validation Server Program (PVSP)  400  typically is stored in a memory, represented schematically as memory  250  in  FIG. 2B . As depicted in  FIG. 2B , memory  250  includes Policy Validation Server (PVS) and Checksum Log  260  with which PVSP  400  interacts. The term “memory,” as used herein, includes without limitation any volatile or persistent medium, such as an electrical circuit, magnetic disk, or optical disk, in which a computer can store data or software for any duration. A single memory may encompass and be distributed across a plurality of media. Thus,  FIG. 2A  and  FIG. 2B  are included merely as a descriptive expedient and do not necessarily reflect any particular physical embodiment of memory  200  and memory  250 . 
       FIG. 2C  is a depiction of the overall auditing system. As will be explained in greater detail below, PVMP  300  interacts with the Workflow Engine (WE) to create a Workflow Representation (WR) (Step  1 ). The WR is sent by secure transmission to the Policy Validation Server (PVS) (Step  2 ). The PVS generates a success or failure notification and report (Step  3 ). The success or failure notification and report are returned to the Workflow Engine (Step  4 ). 
       FIG. 3  illustrates the logic of Policy Validation Mechanism Program (PVMP)  300 . PVMP  300  starts ( 302 ) and a determination is made whether a random interval has occurred ( 304 ). (Persons skilled in the art are aware of numerous methods and devices for generating a random interval.) If not, PVMP  300  waits for the occurrence of a random interval ( 306 ). If a random interval has occurred, PVMP  300  converts the workflow to a workflow representation (WR) ( 308 ), and sends the WR to the Policy Validation Server (PVS) ( 310 ). PVMP  300  receives a response back from the PVS ( 312 ) and determines whether the WR was successfully validated ( 314 ). If the validation was not successful, PVMP  300  receives a report ( 320 ), suspends the workflow ( 322 ), takes corrective action on the Workflow based on the report ( 324 ), and returns to step  308  where the corrected workflow is converted into a new WR to be send to the PVS. If the validation was successful, a determination is made whether the workflow is completed ( 316 ). If the workflow is not completed, the workflow execution continues ( 318 ) and PVMP goes to step  304 . If the workflow is completed, PVMP stops ( 326 ). 
       FIG. 4  illustrates the logic of Policy Validation Server Program (PVSP)  400 . PVSP  400  starts ( 402 ) and receives a WR ( 404 ). PVSP  400  identifies the WR ( 406 ), interrogates the WR ( 408 ), and determines the steps being performed in the WR ( 410 ). PVSP  400  compares the steps in the WR to the appropriate security policy for the identified WR ( 412 ). PVSP  400  determines whether the WR complies with the security policy ( 414 ). If not, PVSP goes to step  438 . If the WR complies, PVSP  400  performs a checksum on the WR ( 416 ) and uses the checksum to determine what operation is being executed with the workflow ( 418 ). PVSP  400  also uses the checksum to determine a snapshot of what the workflow represents ( 420 ). PVSP  400  then validates the checksum ( 422 ). If the checksum is validated, PVSP  400  determines whether the validation is an initial verification ( 424 ). If the validation is an initial verification, PVSP  400  logs the checksum on the PVS ( 436 ) and goes to step  428 . If the validation is not an initial verification, PVSP  400  logs the checksum and compares the checksum to previously logged checksums ( 426 ). PVSP determines from the comparison of checksums, whether a policy changed during execution ( 428 ). If so, PVSP goes to step  438 . If not, PVSP  400  returns a success response to the WE ( 430 ) and determines whether the verification is a final verification ( 432 ). If the verification is not final, PVSP  400  stops. If the verification is final, PVSP  400  executes cleanup logic ( 434 ) and then stops ( 452 ). 
     At step  438  a determination is made whether warnings management has been enabled. If so, one or more warning reports are sent ( 440 ). PVSP  400  waits for a response to the warning reports ( 444 ) and receives workflow approvals ( 446 ). Based on the workflow approvals, PVSP  400  determines whether to change its response ( 448 ). If not, PVSP  400  goes to step  442  and returns a failure response to the WE, returns a report to the WE ( 450 ), and stops ( 452 ). If PVSP  400  changes its response from failure to success, PVSP  400  goes to step  430 . 
     A preferred form of the invention has been shown in the drawings and described above, but variations in the preferred form will be apparent to those skilled in the art. The preceding description is for illustration purposes only, and the invention should not be construed as limited to the specific form shown and described. The scope of the invention should be limited only by the language of the following claims.