Patent Publication Number: US-7719708-B2

Title: Secured release method and system for transmitting and imaging a print job in which a security attribute in the print job header will prevent acceptance of subsequent data packets until a user performs authentication on the imaging device

Description:
BACKGROUND OF INVENTION 
   The present invention is directed to a secured release system to transmit and image a print job, and more specifically to a system for securing the release of the transmission, rendering, and outputting of a print job at an imaging device, for print jobs that originate in traditional print spooling subsystems. 
   In today&#39;s business environments, it is often advantageous to provide one peripheral device to service multiple users. For example, as shown in  FIG. 1 , users (e.g. a group of secretaries, an accounting department, or all the employees in a small business) working at host devices  100  (e.g. computers) may be networked to a single imaging device  102 . An imaging device  102  may be, for example, an MFP (Multi-Function Peripheral/Printer/Product), a printer, a facsimile machine, a copier, a scanner, a filing device, a document conversion device, or any imaging device known or yet to be discovered. In the simplest configuration, the users request the imaging device&#39;s services, and the imaging device  102  automatically provides the services (e.g. automatic printing). Because the imaging device  102  is generally located remote from at least some of the users, it is often desirable to provide some form of interactive printing. Interactive printing provides some form of security to ensure privacy, confidentiality, and/or simply that the correct user will be able to pick up his “print job” (which includes any type of imaging job including, but not limited to print, fax, copy, scan, and document manipulation) without it being picked up by another user, misplaced, or discarded. 
   A spooler  104  transmits print data to a printer by entering (“spooling”) the print data from client host devices  100  in a queue in order (e.g. the order of reception) and outputting (“de-spooling”) the print data in a predetermined or dynamically prioritized order to the printer. Exemplary traditional print spooling subsystems include those found in MS WINDOWS® and AS/400®. Any device or mechanism capable of entering the print data from client host devices  100  in a queue, for purposes of this description, will be referred to as a spooler  104 . Any application, device, or mechanism capable of outputting the print data to the printer, for purposes of this description, will be referred to as a de-spooler  106 . 
   Users often want to transmit print jobs securely.  FIGS. 2-6  show prior art systems used to transmit and image print jobs. All the prior art methods, however, have significant problems. 
     FIG. 2  shows an apparatus used in an encryption method of automatic printing that prevents unauthorized access to a print job by encrypting the print job. In one such encryption method, an unsecured print job  114   a  is encrypted (encrypted print job  114   b ) at the host device  100  during the de-spooling process and decrypted (decrypted print job  114   c ) on the imaging device  102 . It should be noted that the print job may be encrypted either at the transport layer or data layer, between the host device  100  and the imaging device  102 . While this method provides security from unauthorized access during the transmission, it does not protect the print job from being accessed after the print job  114   d  has been output to an output bin  116 . 
     FIG. 3  shows an apparatus used in a secured release output bin method of interactive printing. In this method, a confidential print job  118   a  is imaged and output/held in secured release output bin  116   a  that is physically secured (e.g. using a lock and mechanical key) to prevent unauthorized retrieval or access to the print job  118   a . Using a release mechanism (e.g. a key), the user is able to obtain access to an output bin  116   b  holding his print job  118   b . It should be noted that the print job  118   a  in the output bin  116   a  is the physical document (print job  118   b ) that is in the output bin  116   b , after the print job has been released. A variation of this system could include a mail-boxing system and sorter for feeding sheets from an imaging device  102  into multiple physically secured output bins where each output bin  116   a  is individually physically secured. When a user wants to keep his print job  118   a  confidential, he directs the output of the print job  118   a  to the respective secured output bin  116   a  to which he has physical access. One disadvantage of this method is that it requires a specially designed output bin. The multiple output bin  116   a  embodiment also requires a sufficient number of output bins  116   a  for distinct users with secured release rights (e.g. those having a key). Another disadvantage of this method is that it does not support any form of ad-hoc secured release. 
     FIG. 4  shows an apparatus used in a coded memory release method of interactive printing (“confidential print” or PIN printing). A confidential print job  122   a  (shown as Non-Output Imaged/Print Job  122   a ) is imaged and output/held in secured memory  120  that is secured using a coded virtual locking system (e.g. a code or personal identification number (PIN), herein after referred to as a secure release code  124 ) to prevent unauthorized retrieval or access to the confidential print job  122   a . In this method, the secured memory  120  is memory or internal storage of the imaging device  102 . The user may assign a secure release code  124  to a print job by entering the secure release code  124  during the generation of the print job. The secure release code  124  is generally hashed (one-way encryption) and the hash value is added to the confidential print job  122   a . When the imaging device  102  receives the confidential print job  122   a  it is fully rasterized (RIP) as a confidential print job  122   a  to be held in the secured memory  120 . The owner of the confidential print job  122   a  can then release the confidential print job  122   a  by entering the respective secure release code  124  at the operations panel  126  of the imaging device  102 . Generally, the device will hash (e.g. MD5) the entered secure release code  124 , using the same hash algorithm at the client side and compare it to the hash value stored in the confidential print job  122   a . The RIP pages of the confidential print job  122   a  are then developed and output as an output print job  122   b . One disadvantage of this method is that the RIP confidential print jobs  122   a  consume considerable storage space in the secured memory  120  of the imaging device  102 . The secured memory  120  would have to have sufficient storage capacity to allow other secured and non-secured release jobs to be processed on the imaging device  102  while the RIP confidential print jobs  122   a  are stored. Thus, this may severely limit the number of confidential print jobs that can be processed at a time and, potentially, limit the number of non-confidential print jobs. Another disadvantage of this method is that if the imaging device  102  is physically compromised and the secured memory  120  is accessed while the RIP confidential print jobs  122   a  are stored, even if the confidential print jobs  122   a  are encrypted, they may contain visible “unencrypted” content. Yet another disadvantage of this method is that if confidential print jobs  122   a  are forgotten (i.e. not picked up by the issuer), the storage space used by the RIP confidential print jobs  122   a  is indefinitely consumed until an operator with the appropriate authorization is able to delete the confidential print jobs  122   a  from secured memory  120 . 
     FIG. 5  shows an apparatus used in a coded memory execution and release method of interactive printing. In this method, both the host device  100  and imaging device  102  have an ID reader  130  (e.g. an optical reader) for entering an ID card  132 . When the user submits a print job  134   a , he inserts his ID card  132  into the ID reader  130  at the host device  100 . The host device  100  imaging system then adds an ID code, generally hashed, to the print job  134   a  and transmits the ID code and print job to the imaging device  102  as unexecuted print job  134   b . The unexecuted print job  134   b  is then stored in the imaging device  102 . The user can access and execute (e.g. RIP and output) the print job  134   c ,  134   d  by entering his ID card  132  at the ID reader  130  of the imaging device  102 . One disadvantage of this method is that the unexecuted print jobs  134   b , while not RIP, can still consume significant storage space in the imaging device  102  memory. Another disadvantage of this method is that if the imaging device  102  is physically compromised and the storage therein is accessed while the unexecuted print job  134   b  is stored, the unexecuted print job  134   b  can be retrieved. If the unexecuted print job  134   b  is unencrypted, it could be processed at a different location to reveal the content. If the unexecuted print job  134   b  is encrypted, its contents could still be accessed if the encrypted code is hacked. Yet another disadvantage of this method is that if secured unexecuted print jobs  134   b  are forgotten (i.e. not picked up by the issuer) the storage space used by the forgotten unexecuted print job  134   b  is indefinitely consumed. 
     FIG. 6  shows an apparatus used in a remotely stored method of interactive printing. In this method, the user sends the print job  140   a  from the host device  100  to a secure release print server  142  along with a secure release code  143 . The print job  140   b  is then held on the print server  142 . The user releases the print job  140   b  by entering the secure release code  143  at the operation panel  144  of the imaging device  102 . The imaging device  102  then contacts the secure release print server  142 , passing it the entered secure release code  143 . The print server then de-spools to the imaging device  102  the print job  140   c  related to the secure release code  143 . The print job is then developed  140   d  and output as an output print job  140   e  to the output bin  116 . While the print job is not held in a secured release mode on the imaging device  102 , this method still suffers in that the print job  140  is held (taking up memory) at an intermediate location (i.e. secure release print server  142 ) between the host device  100  and the imaging device  102 , which could be compromised. For example, an operator with print administration rights on the secure release print server  142  could make a copy of the print job  140   c  and process the print job  140   c  at another location. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention is directed to an effective method for securing the release of the transmission, rendering, and outputting of an imaging/print job at an imaging device, for imaging/print jobs that originate in traditional print/spooling subsystems. 
   The method includes the following steps. A print job header is associated with a first imaging/print job to form a headed imaging/print job. A secured release input (that may be input at a secured release input apparatus of a client host device) is associated with the print job header by including a secured release indicative command/code in the print job header. The headed imaging/print job is divided into data packets. Initial data packet(s) are transmitted to the imaging device. It is determined whether the secured release indicative command/code is present in the initial data packet(s). Acceptance of subsequent data packets of the headed imaging/print job are prevented if the secured release indicative command/code is present in the initial data packet(s). 
   When a secured release input is received on a secured release input apparatus of the imaging device, subsequent data packets of the headed imaging/print job are accepted. 
   In one preferred embodiment, the subsequent data packets are retained on the client host device until they are released. 
   In one preferred embodiment, the pre-existing print subsystem does not need to be modified. 
   The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       FIG. 1  illustrates an exemplary computer network environment for implementing the system and method of the present invention. 
       FIG. 2  is a schematic diagram of a prior art embodiment of a host device and imaging device for implementing an encryption method of interactive printing. 
       FIG. 3  is a schematic diagram of a prior art embodiment of a host device and imaging device for implementing a secured release output bin method of interactive printing. 
       FIG. 4  is a schematic diagram of a prior art embodiment of a host device and imaging device for implementing a coded memory release method of interactive printing. 
       FIG. 5  is a schematic diagram of a prior art embodiment of a host device and imaging device for implementing a coded memory execution and release method of interactive printing. 
       FIG. 6  is a schematic diagram of a prior art embodiment of a host device and imaging device for implementing a remotely stored method of interactive printing. 
       FIG. 7  is a flow diagram of a header in the input analyzer of an imaging device using one exemplary method of the present invention. 
       FIG. 8  is a schematic diagram of an exemplary system of the present invention including a host device and an imaging device for implementing a host device stored release method of interactive printing. 
       FIG. 9  is a schematic diagram of an internal imaging job queue for storing confidential and non-secured release print jobs on an imaging device. 
       FIG. 10  is a schematic diagram of one preferred two-host system in which I/O of a secured release print job from one host device is prevented from being accepted while I/O of a non-secured release print job from another host device is accepted. 
       FIG. 11  is a schematic diagram of a preferred one-host system in which I/O of a secured release print job from a host device is prevented while I/O of a non-secured release print job from the same host device is accepted. 
       FIG. 12  is a schematic diagram of a preferred one-host system with multiple logical input channels/ports to connect to multiple imaging devices so that after acceptance is prevented of a secured release print job, the host may continue to print other print jobs from other logical input channels/ports which have received acceptance or do not require acceptance. 
       FIG. 13  is a schematic diagram of a single input channel/port of a host device connected to a single imaging device. 
       FIG. 14  is a schematic diagram showing one preferred method for the secured release of the secured release print job. 
       FIG. 15  is a simplified block diagram showing a specialized interspersed device functionally between the client host device and the imaging device, the specialized interspersed device providing at least some of the functions of the client host device. 
       FIG. 16  is a simplified block diagram showing a specialized interspersed device functionally between the client host device and the imaging device, the specialized interspersed device providing at least some of the functions of the imaging device. 
       FIG. 17  is a simplified block diagram showing the client host device de-spooling the initial sub-portion of the print job to a plurality of imaging devices  102  to implement a “follow me” or “print anywhere” form of printing. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The present invention is directed to an effective system for securing the release of an imaging/print job, where the imaging/print job is retained on the client host device  100  until it is securely released to an imaging device  102 . 
   The present invention uses a headed imaging/print job  150  ( FIG. 7 ) that includes a print job header  152  and an imaging/print job  154   a . If the imaging/print job (e.g. a document) is to be securely released, the print job header  152  includes a secured release indicative command/code  156 . The headed imaging/print job  150  may be divided into data packets (shown as  150   a ,  150   b ,  150   c ). 
   The system preferably works with a pre-existing host device  100  and its print subsystem (e.g. print spooler  104  and de-spooler  106  (e.g. print processor and port monitor)). Preferably the host device  100  print subsystem does not need to be modified except for the installation of a corresponding imaging device driver  160  (e.g. a printer driver). The imaging device driver  160  may be installed as software or may be a hardware/firmware device. An optional specialized secured release input apparatus  164  (which is a system that accepts a secured release input (SRI)  162 ) may also be added to the host device  100 . 
   Another component of the present invention is the input analyzer  170  ( FIG. 7 ). An initial data packet  150   a  is sent to the input analyzer  170 . If the input analyzer  170  determines that a secured release indicative command/code  156  is present in the print job header  152  (which may be in one or more initial data packets  150   a ), the imaging device  102  prevents acceptance of subsequent data packets (e.g.  150   b ,  150   c ) on the corresponding logical channel/port from which the headed imaging/print job  150  originates. “Preventing acceptance” can be accomplished by blocking or suspending receipt of subsequent data packets (e.g.  150   b ,  150   c ) on a corresponding logical channel(s)/port(s). 
   The present invention could be implemented as a specialized imaging device  102  that includes an input analyzer  170  and a mechanism for entering a secure release input  162 . The present invention could also work with less sophisticated or pre-existing imaging devices  102 . One way that the present invention could work with any imaging device  102  would be to modify the imaging device  102  to include an input analyzer  170  and/or a mechanism for entering a secure release input  162 . Another way that the present invention could work with a pre-existing imaging device  102  would be to provide a specialized interspersed device (see  FIGS. 15 and 16 ) functionally between the de-spooler  106  of the client host device  100  and the imaging device  102 . The specialized interspersed device could include, for example, an input analyzer  170  and/or a mechanism for entering a secure release input  162 . 
   In preferred embodiments, while preventing acceptance of a secured release print job on one logical channel/port, other print jobs (secured or non-secured) may be received and analyzed on other logical channels/ports. 
   From a user&#39;s point of view, requesting imaging of a secured release print job using the present invention is a simple procedure. If the user wants to print a confidential document using the secured release feature, the user requests imaging of the imaging/print job  154   a  from an application program (e.g. MS-Word®). The user is then prompted to enter a secured release input  162  that he enters at the secured release input apparatus  164  of the host device  100 . The user subsequently goes to an associated imaging device  102  to retrieve the print job. It should be noted that preferred embodiments of the present invention would allow the user to delay print job retrieval without delaying the imaging of other users&#39; print jobs. To retrieve the print job ( FIG. 14 ), the user enters the secured release input  162  on the secured release input apparatus  166  of the imaging device  102  (shown as operations panel  166 ). The user then removes the imaging/print job  154   b  from the output bin  116  of the imaging device  102 . 
   Headed Imaging/Print Job 
     FIG. 7  shows an exemplary headed imaging/print job  150  that includes a print job header  152  and an imaging/print job  154   a  (e.g. imaging data). The print job header  152  may be any type of initial portion added to, augmented to, appended to, incorporated into, linked with, or transformed to include or be included with (herein afterwards referred to as “associated with”) the imaging/print job  154   a . The print job header  152  may take the form of a separate portion, a file, commands, and/or code. In preferred embodiments of the present invention, the print job header  152  includes a secured release indicative command/code  156  if the document is to be securely released. The secured release indicative command/code  156  may be added to, augmented to, appended to, incorporated into, linked with, or transformed to include or be included with (herein afterwards referred to as “associated with”) the print job header  152 . The print job header  152  may include other information such as job wide settings  158   a , trailing data  158   b , and other settings, commands, and/or code. The headed imaging/print job  150  may be divided into data packets (shown as  150   a ,  150   b ,  150   c  in  FIG. 8 ). 
   The secured release input  162  is “related to” the secured release indicative command/code  156  of the print job header  152 . “Related to” means that the secured release input  162  and secured release indicative command/code  156  may be matched, analyzed, found (e.g. using a look-up function), or otherwise compared or contrasted such that appropriate secured release inputs  162  will allow access to documents having the respective secured release indicative command/codes  156 . 
   It should be noted that the secured release input  162  that is input at the secured release input apparatus  164  of the host device  100  may be different from the secured release input  162  that is input at the secured release input apparatus  166  at the imaging device  102 . It should also be noted that there may be more than one secured release input  162  that corresponds to each secured release indicative command/code  156 . For example, there may be a master secured release input  162  that would release all secured release print jobs. 
   It should be noted that the headed imaging/print job  150  may be divided into data packets (shown as  150   a ,  150   b ,  150   c ) of the same size or of different sizes. It should also be noted that the size(s) may be pre-determined, specified by the user, or determined dynamically. In one embodiment, at least the first initial data packet is set to be the exact size of the print job header  152 . 
   For exemplary purposes, the generation of a headed imaging/print job  150  may be accomplished using the following methods. In one method, a headed imaging/print job  150  may be generated using an imaging device driver  160  to convert application data to headed imaging/print job  150 . In another method, a direct submit application produces a headed imaging/print job  150  that is subsequently transformed or augmented to include the secured release input  162 . The direct submit application then encapsulates the application/image data with the secured release input  162  (where the native format of the data is interpreted by the imaging device  102 ). 
   Input Analyzer 
     FIG. 7  shows the process used by the input analyzer  170 . The input analyzer  170  determines whether a secured release indicative command/code  156  is present in the print job header  152 . If it is found, the imaging device  102  prevents acceptance of subsequent data packets on the corresponding logical channel/port from which the headed imaging/print job  150  originated. 
   As shown in  FIG. 7 , at least one initial data packet  150   a  of a headed imaging/print job  150  is sent to the input analyzer  170 . As the imaging device  102  receives the initial data packet(s)  150   a  of the print job, the input analyzer  170  pre-reads  172  the data to detect a secured release indicative command/code  156  that is indicative of a secured release print job. Pre-reading may be thought of as performing an analysis on the data prior to the acceptance of subsequent packets. If the end of the print job header  152  has not been reached 173, the next initial data packet(s)  150   a  will be accepted  174 . The data indicative of the end of the print job header  152  may be a pre-known command syntax, such as the PJL statement @PJL ENTER LANGUAGE=&lt;format&gt; as specified by Hewlett Packard PJL command syntax. 
   Once the complete print job header  152  has been received 173 (e.g. the data packet with the end of print job header  152  is encountered), a determination is made as to whether a secured release indicative command/code  156  has been detected. As part of the analysis process of this determination, the data packet(s) is parsed for data indicative of a secured release indicative command/code  156  according to a pre-known command syntax, such as the print job language (PJL) statement @PJL SET SUSPENDKEY=“&lt;PIN&gt;” implemented by the Sharp AR-507 and AR-M450 digital imaging devices. 
   If no such secured release indicative command/code  156  is detected  175  in the print job header  152 , the print job is treated as normal and is fully accepted  176 , received, and queued in the imaging device  102 . In general, normal processing means that the imaging device  102  continues to accept data packets without suspension according to its storage and bandwidth capacity. 
   On the other hand, if a secured release indicative command/code  156  is encountered, the input analyzer  170  may designate or tag the headed imaging/print job  150  as being confidential (e.g. a secured release print job). If the print job is confidential, the imaging device  102  prevents acceptance  177  of subsequent data packets (e.g.  150   b ,  150   c ) on the corresponding logical channel/port associated with the print job. It should be noted that preventing acceptance  177  may be accomplished by blocking (the I/O output from the port monitor on the client host device  100  is blocked) or suspending receipt of subsequent data packets (e.g.  150   b ,  150   c ) on corresponding logical channel(s)/port(s). This prevention of acceptance may be implemented at the transport layer. If a secured release indicative command/code  156  is discovered, subsequent data packets may, optionally, not be analyzed by the input analyzer  170 . 
   The logical channel/port then stays in a suspension mode until the user initiates the secured release. To retrieve the print job, the user would enter the secured release input  162  on the operations panel  166 . 
   It should be noted that the shown order of the process in  FIG. 7  is exemplary and may be modified. For example, if the secured release indicative command/code  156  is detected during the pre-read step  172 , the imaging device  102  can immediately prevent acceptance of subsequent data packets. This is shown with the phantom line between pre-read step  172  and detected step  175 . 
   It should be noted that while the data packets are being analyzed, the input analyzer  170  may parse the data for commands indicative of other print job attributes that would facilitate a user in identifying his print job, such as the job name, the document name, and the user name. 
   The input analyzer  170  may, for example, be installed/added to the system as a software upgrade, preinstalled as software, or implemented as hardware. 
   Exemplary Embodiments 
     FIG. 8  shows an exemplary preferred embodiment of the present invention in which the user requests the imaging of a secured release imaging/print job  154   a . Specifically, this figure shows a client host device  100  having a pre-existing imaging spooling/de-spooling subsystem  104 ,  106  (host device print subsystem) and an imaging device (printer) driver  160 . The pre-existing host device  100  print subsystem includes, for example, a print spooler  104 , a graphical display interface (GDI) in MS-WINDOWS®, and a de-spooler  106 . The imaging device driver  160  may be used for generating a print job with an embedded instruction that indicates a secured release print job. For purposes of this example, the imaging device  102  includes an input analyzer  170  and a mechanism (operations panel  166 ) for entering a secure release input  162 . 
   After a print job is created using an application program (e.g. a word processing program, a spread sheet program, or a graphic program), the user requests imaging (initiates the de-spooling) of a secured release print job from the application program (or a secondary program). For example, the user may initiate the de-spooling of a print job by scheduling a print job through the print spooler  104 . 
   The user may be prompted to enter a secured release input  162 , which he enters at the secured release input apparatus  164 . Alternatively, a secured release input  162  may be automatically applied to all print jobs originating from a particular host device  100 , to all print jobs having pre-defined destinations, or to some other subset of print jobs. 
   The imaging device driver  160  creates a headed imaging/print job  150  associated with the secured release input  162  (or other command/code indicative of the secured release input  162 ), preferably in a print job header  152 . The headed imaging/print job  150  (imaging device ready data) is preferably prepared in a series of data packets  150   a ,  150   b ,  150   c . The initial data packet(s)  150   a  preferably includes all or part of the print job header  152 . 
   The headed print job  150  is spooled to the print spooler  104  and de-spooled to the imaging device  102 . For example, the de-spooler could be a print processor and port monitor invoked via a spooler thread specific to the driver  160 . The port monitor, running under the imaging device specific spooler thread, initiates a protocol (e.g. line printer remote (LPR)) for transmitting the print job to the imaging device  102  in a stream of data packets  150   a ,  150   b ,  150   c . Once the host device  100  print subsystem starts the de-spooling of the print job, the spooler  104  creates or assigns the spooler thread specific to the imaging device  102 , and initiates the de-spooling process from this specific thread. The spooler parent and other child threads continue to run asynchronous to this specific thread. 
   The de-spooling process establishes a connection to the imaging device  102  (e.g. TCP/IP in a network connected imaging device  102 ) via a logical channel/port (e.g. LPR, IPP, 9100 port). Using a logical channel/port, multiple client host devices  100  can establish simultaneous connections to the same channel/port of an imaging device  102  (e.g. as shown in  FIG. 10 ). Further, using a logical channel/port, a single client host device  100  can establish simultaneous connections to the same channel/port of an imaging device  102  (e.g. as shown in  FIG. 11 ). Still further, using a logical channel/port a single client host device  100  can establish multiple simultaneous connections to multiple imaging devices  102  over different channels/ports (e.g. as shown in  FIG. 12 ). 
   Once the connection to the logical channel/port is established, the client host device  100  and imaging device  102  use a printing protocol to transfer the print job in a sequential sequence of data packets. A protocol handshaking occurs between the client host device  100  and imaging device  102  to acknowledge receipt/acceptance of each data packet. 
   As the imaging device  102  receives the initial data packet(s)  150   a  of the print job, the input analyzer  170  determines whether a secured release indicative command/code  156  is present in the print job header  152 . If no such secured release indicative command/code  156  is detected  175  in the print job header  152 , the print job is treated as normal and is fully accepted  176 , received, and queued in the imaging device  102 . However, if a secured release indicative command/code  156  is found, the imaging device  102  prevents acceptance of subsequent data packets (e.g.  150   b ,  150   c ) on the corresponding logical channel/port from which the headed imaging/print job  150  is being sent. 
   The logical channel/port then stays in a suspension mode until the user initiates the secured release as discussed in connection with  FIG. 14 . 
   The specifics of the embodiment shown in  FIG. 8  are provided for purposes of best mode and enablement and are not meant to limit the scope of the invention. 
     FIG. 9  shows an example of how the imaging device  102  queues (imaging/print job queue  180 ) non-secured release print jobs  180   a  (e.g. automatic print jobs) and secured release print jobs  180   b  (headed imaging/print job  150 ). In this embodiment, the imaging device  102  has the capability to store some, if not all, of a print job in imaging/print job storage  182  (e.g. storage such as RAM, a hard disk, or an externally secured storage device). 
   For non-secured release print jobs  180   a , the entire print job  182   a  may be stored in imaging/print job storage  182  until the imaging device  102  is ready to process the print job. For secured release print jobs  180   b , only the sub-portion of the print job  182   b  up to the initial data packet(s)  150   a  containing the secured release indicative command/code  156  is stored in imaging/print job storage  182  until the print job is securely released and the imaging device  102  is ready to process the secured release print jobs  180   b . The remaining data packets (e.g.  150   b ,  150   c ) containing the confidential imaging/print job  154   a  remains on (or are retained by) the host device  100  that, presumably, is more secure. 
   Using the imaging/print job storage  182  shown in  FIG. 9  creates two significant advantages of the present invention: security and memory savings. Since only a sub-portion of the print job  182   b  (primarily the print job header  152 ) of the secured release print jobs is stored in the imaging/print job storage  182  of the imaging device  102 , little if any secure information may be retrieved from the imaging device  102  should security be compromised. Since only a sub-portion of the print job  182   b  of the secured release print jobs is stored in the imaging/print job storage  182  of the imaging device  102 , there is significant memory/storage space savings. 
     FIG. 10  shows an example of how the imaging device  102 , while preventing acceptance (shown as “blocked”) of a secured release print job  184  (shown as  184   a - d ) from a first host device  100  (Host A), may receive print jobs  186  (shown as  186   a - d ) from a second host device  100  (Host B). This figure can be interpreted as showing Host A sending initial data packet(s)  184   a  of a secured release print job  184  to the imaging device  102 . The remaining blocked/suspended data packet(s)  184   b - d  remains on Host A. Before, during, or after Host A sends the initial data packet(s)  184   a , Host B sends a non-secured release print job  186  (shown in progress with data packets  186   a - b  transmitted to the imaging device  102  and data packets  186   c - d  to be transmitted). Without waiting for the secured release print job  184  to be imaged, the imaging device  102  can image the non-secured release print job  186  so that a user may remove it from the output bin  116  of the imaging device  102 . 
   One exemplary method for creating the scenario shown in  FIG. 10  would be to have the imaging device  102  prevent acceptance of data packets  184   a - c  for the secured release print job  184  on a logical channel/port, while simultaneously receiving/accepting data  186  on other logical channels/ports. For example, if the imaging device  102  is shared, the input process could begin, or continue to, accept a print job from a different client host device  100  on the same or different channel/port. For example, both client host devices  100  could be de-spooling to an LPR port. The imager input process manages simultaneous input on the same channel/port from different client host devices  100  by creating a pool of input threads and assigning a separate thread processing thread to the same channel/port for each distinct network connection (i.e. connections from a different network address). 
     FIG. 11  shows a one-host system embodiment of the present invention in which the imaging device  102  that, while preventing acceptance (shown as “blocked”) of a secured release print job  184  (shown as  184   a - d ), may receive non-secured print jobs  186  (shown as  186   a - d ) from the same host device  100 . This figure can be interpreted as showing the host device  100  sending initial data packet(s)  184   a  of a secured release print job  184  to the imaging device  102 . The remaining blocked/suspended data packet(s)  184   b - d  remains on the host device  100 . Before, during, or after the host device  100  sends the initial data packet(s)  184   a , the host device  100  sends a non-secured release print job  186  (shown in progress with data packets  186   a - b  transmitted to the imaging device  102  and data packets  186   c - d  to be transmitted). Without waiting for the secured release print job  184  to be imaged, the imaging device  102  can image the non-secured release print job  186  so that a user may remove it from the output bin  116  of the imaging device  102 . 
   One exemplary method for creating the scenario shown in  FIG. 11  would be the imaging device  102  beginning to (or continuing to) accept another print job from the same client host device  100  on a different channel/port  187   b  other than the original channel/port  187   a . For example, in MS WINDOWS®, the print spooler  104  creates a separate de-spooling thread per installed imaging device driver  160 . Thus, a client host device  100  could create two logical installed imaging device drivers  160  on the client host device  100  to the same physical imaging device  102 , where the two logical installed imaging device drivers  160  differ in the type of channel/port connection (e.g. LPR and 9100). In this example, the spooler  104  would create separate threads, and while one secured release print job  184  is prevented from being accepted on one thread, the spooler  104  could continue to de-spool a second print job  186  (which may or may not be a secured release print job) to the same imaging device  102 . The imaging device  102  input process manages simultaneous input from different channels/ports  187   a ,  187   b  by assigning a separate processing thread(s) to each channel/port  187   a ,  187   b.    
     FIG. 12  shows an embodiment of the present invention in which multiple logical input channels/ports connect to multiple imaging devices  102  (Imager A and Imager B) so that a host  100  may continue to print after acceptance is prevented (shown as “blocked”) of a secured release print job  184  (shown as  184   a - d ). In this case, the print spooler  104  creates a separate thread(s) for the other installed imaging device driver(s)  160  and initiates the de-spooling of other print jobs simultaneously with the de-spooling secured release print job that has been prevented from being accepted. 
   As shown in  FIG. 12 , a client host device  100  may continue to de-spool print jobs (secured release and non-secured release) to other imaging devices  102  (e.g. Imager B) while a client host device  100  has the de-spooling of a secured release print job  184  (shown as  184   a - d ) prevented from being accepted by a first imaging device  102  (Imager A). Specifically, this figure shows a one-host/two imager system exemplary alternative preferred embodiment of the present invention in which the first imaging device  102  (Imager A) prevents acceptance of a secured release print job  184  (shown as  184   a - d ) while the second imaging device  102  (Imager B) receives a non-secured print jobs  186  (shown as  186   a - d ) from the same host device  100 . This figure can be interpreted as showing the host device  100  sending initial data packet(s)  184   a  of a secured release print job  184  to the imaging device  102  (Imager A). The remaining blocked/suspended data packet(s)  184   b - d  remains on the host device  100 . Before, during, or after the host device  100  sends the initial data packet(s)  184   a , the host device  100  sends a non-secured release print job  186  (shown in progress with data packets  186   a - b  transmitted to the imaging device  102  (Imager B) and data packets  186   c - d  to be transmitted). Without waiting for the secured release print job  184  to be imaged on the first imaging device  102  (Imager A), the second imaging device  102  (Imager B) can image the non-secured release print job  186  so that a user may remove it from the output bin  116  of the imaging device  102  (Imager B). 
     FIG. 13  shows an embodiment of the present invention in which a single input channel/port of a host device  100  connects to a single imaging device  102  with a single logical channel/port. In this embodiment, if the user attempts to de-spool a second imaging/print job  188  to the same logical channel/port on the imaging device  102  while a secured release print job  184  is prevented from being accepted (shown as “blocked”) on the logical channel/port from the same host device  100 , the second imaging/print job  188  would remain queued on the client host device&#39;s local imaging queue (e.g. print queue), until the first secured release print job  184  is accepted and fully de-spooled. 
   It should be noted, however, that the problem depicted in  FIG. 13  could be solved by using multiple logical channels/ports as discussed in connection with  FIG. 11 . For example, the client host device  100  could create two logical installed imaging device drivers  160  on the client host device  100  to the same physical imaging device  102 , where the two logical installed imaging device drivers  160  differ in the type of channel/port connection (e.g. LPR and 9100). In more advanced host device  100  print subsystems, an imaging device  102  and a host device  100  spooler  104 /de-spooler  106  may support simultaneous de-spooling of multiple print jobs from the same client host device  100  to the same channel/port. Such a method is disclosed in U.S. patent application Ser. No. 10/925,602, which is incorporated herein by reference. 
     FIG. 14  shows an exemplary preferred embodiment of a secured release method for releasing the secured release print job that has been prevented from being accepted (shown as “blocked”) at the imaging device  102 . To retrieve the secured release print job, the user would, for example, enter the secured release input  162  on the operations panel  166  of the imaging device  102 . Alternatively, the user could enter the secured release input  162  on alternative secured release input apparatus  166  and/or remotely through an embedded Web page. When the secured release print job is securely released, the imaging device  102  resumes acceptance of data packets (e.g.  150   b ,  150   c ,  150   d ) on the logical channel/port as the port monitor on the host device  100  is “unblocked” or “unsuspended.” This can be distinguished from known pull systems in which a request is sent to a host or server to transmit the print job. In the present invention, the print job is in a suspension mode on a logical channel/port and is just waiting for the logical channel/port to be “unblocked” or “unsuspended.” The input analyzer  170  may “resume acceptance” of the data packets by allowing the remainder of the data packets (e.g.  150   b ,  150   c ,  150   d ) to be transmitted to the imaging device  102 . (The initial data packet  150   a  preferably has been maintained in the imaging device.) The processing of the print job may then proceed as normal. For example, the imaging device  102  images and outputs the print job. The user may then remove the output imaging/print job  154   b  from the output bin  116  of the imaging device  102 . 
     FIG. 15  shows an embodiment in which a specialized interspersed device  190  (e.g. print server) may be functionally between the client host device  100  and the imaging device  102 , the client host device  100  and the specialized interspersed device  190  together functioning as the client host device side. Using this system, the host device  100  transmits the secured release print job to the specialized interspersed device  190  which, in turn, transmits the secured release print job to the imaging device  102 . After the client host device  100  initially de-spools the print job to the interspersed device  190 , the specialized interspersed device  190  functions, at least partially, as the client host device  100 . For example, the specialized interspersed device  190  may functionality de-spool the print job to the imaging device  102 , may provide additional logical channel(s)/port(s), and/or release the print job to the imaging device  102 . In this embodiment the imaging/print job is retained on the specialized interspersed device  190  (which is functioning as the client host device side) until it is securely released to the imaging device  102 . It should be noted that the embodiments of  FIGS. 8-14  and  18  could be implemented using the specialized interspersed device  190 . 
     FIG. 16  shows an embodiment in which a specialized interspersed device  192  (e.g. print server) may be functionally between the client host device  100  and the imaging device  102 , the imaging device  102 _and the specialized interspersed device  192  together functioning as the client host device side. In this embodiment the specialized interspersed device  192  at least partially provides functions of the imaging device side. For example, the specialized interspersed device  192  may prevent acceptance (including the functionality of the input analyzer  170 ), may provide storage/memory (e.g. for initial sub-portions of the headed imaging/print job  150   a ), may provide additional logical channel(s)/port(s), and/or may function as the operations panel  166 . This embodiment could be implemented as a specialized box that is positioned on or near a standard imaging device  102 . Using this system, the host device  100  transmits the secured release print job to the specialized interspersed device  192  which, in turn, transmits the secured release print job to the imaging device  102  when the secure release input  162  is input. It should be noted that the embodiments of  FIGS. 8-14  and  18  could be implemented using the specialized interspersed device  192 . 
     FIG. 17  shows an embodiment of the present invention in which the client host device  100  de-spools the initial sub-portion  194  (data packet(s) with print job header  152 ) of the print job to a plurality of imaging devices  102 . This allows the system to be implemented as a “follow me” or “print anywhere” form of printing. After the initial sub-portion  194  of the print job is de-spooled to a plurality of imaging devices  102 , the user may then securely release the print job from any one of the plurality of imaging devices  102 . Once securely released, the remaining imaging devices  102  are notified and purge their copy of the initial sub-portion  194  of the print job. 
   It should be noted that the present invention may include an input/output (I/O) timeout configured to wait for a secured release. The timeout can be configured to allow sufficient time for the user to securely release the imaging/print job. If the user fails to enter the secure release code before the expiration of the timeout, the device or host would then terminate the connection and purge the imaging/print job. The timeout can be also be configured to purge the imaging/print job after the timeout is exceeded (which could result in a lost imaging/print job). The host device  100 , upon detection of the terminated connection, could purge its portion of the imaging/print job. In this manner, the system can be configured to prevent lost or forgotten imaging/print job from wasting valuable system resources. The input/output (I/O) timeout may be implemented on the client host device  100  and/or the imaging device  102 . 
   Miscellaneous 
   For purposes of this invention, a “print job” or “imaging job” includes traditional print jobs as well as faxing, copying, scanning, document manipulation, and other nontraditional print jobs. Other embodiments could include document management, such as document archive/retrieval, manipulation, and transfer. The print job may also have other security related attributes, such as authorization control and encryption. 
   For purposes of this invention, the secured release input  162  may be any type of identifying information including, but not limited to an ID code, an alphanumeric code, a personal identification number (PIN), a magnetic identification card, a smart card, or biometric information (e.g. a retinal scan or a fingerprint) from a biometric sensor. The secured release input print release mechanism is not limited to secured release, but also includes interactive release without a secured release input  162 . 
   The secured release input  162  may be entered at the host device  100  and/or the imaging device using standard input devices such as a keyboard, a mouse, a microphone, or an operations panel. In an alternative preferred embodiment the secured release input  162  may be entered via specialized hardware. For example, in addition to or as an alternative to using standard input devices, the secured release input  162  may be implemented using specialized secured release input apparatus  164  such as a specialized keypad, magnetic identification card reader, or a biometric sensor (e.g. fingerprint or retinal scanner). 
   It should be noted that additional security measures such as encryption and/or overwriting may be used for particularly sensitive print jobs. 
   The terms and expressions that have been employed in the foregoing specification are used as terms of description and not of limitation, and are not intended to exclude equivalents of the features shown and described or portions of them. The scope of the invention is defined and limited only by the claims that follow.