Patent Publication Number: US-2010118341-A1

Title: Printer terminal and posting server

Description:
BACKGROUND 
     1. Technical Field 
     The present invention relates to a technology for transmitting contents data, which is used for printing a content, through a network. In descriptions here, a “print content” or a “content” represents a document, an image, an information entity acquired by combining the document and the image, or the like that can be printed. 
     2. Related Art 
     Typically, when a company delivers an advertisement or the like to a customer, mail, a facsimile, or the like is used. In addition, in a field of distance learning or the like, when a text providing company delivers a text or the like to students, similarly, by the post, a facsimile, or the like is used. 
     When mailing is used, the print content such as an advertisement or a text that is printed at a high quality can be provided. However, in such a case, a lot of labor is involved in the delivery of the print content. Accordingly, there is a problem that a lot of cost is required, and a time is needed for delivering the print content. 
     In addition, when the facsimile is used, compared to a case where the post is used, less labor and time is required for the delivery of the print content. However, in such a case, there is a problem that communication costs incur, and the print content received from a client cannot be expected to have high quality. Furthermore, in the case where the facsimile is used, it can be checked whether the content has been received by a delivery destination. However, it cannot be checked whether the content is printed so as to be outputted. 
     On the other hand, recently, owing to the development of the Internet and the like, information can be transmitted at a low cost that is close to zero. In addition, owing to the development of a printer, a multifunction device, and the like that have high performance, high-quality printing can be performed at a relatively low cost also in houses. 
     In addition, as technology relating to transmission of information by using a network, for example, the technology has been disclosed in JP-A-2005-109701, JP-A-2003-178028, and JP-T-2005-516320. 
     Accordingly, the development of a system that can deliver the print content with high quality at a low cost by using a network such as the above-described Internet and a printer terminal that includes a printer, a multifunction device, or the like has been waited for. 
     In such a delivery system, it is extremely important for a person sending the print content to acquire whether the print content is assuredly delivered to the print terminal and whether the print content delivered to the printer terminal is printed. 
     SUMMARY 
     An advantage of some aspects of the invention is that it provides technology for acquiring the delivery state and the printing state of the print content in a system in which the print content is delivered at a low cost with high quality. 
     According to a first aspect of the invention, there is provided a printer terminal that is connected to a delivery system including: a posting server that delivers contents data for printing a content to the printer terminal through the network; and a relay server that relays setup of a session between the posting server and the printer terminal based on a delivery request from the posting server through the network by using a signaling protocol; through the network. The printer terminal includes: a communication unit that accepts a session setup request through the relay server, sets up a session with the posting server, and acquires the contents data through a predetermined data transmission protocol by using the session that has been set up; a memory unit that stores the acquired content data and presence information including information that indicates the state of the contents data therein; and a printing unit that performs printing based on the contents data. The communication unit tries transmission of the presence information after update to the posting server when the state of the contents data that is included in the presence information is updated to indicate a reception-completed state or a state in which printing is completed by the printer unit, and does not accept a new session setup request from the posting server through the relay server when the amount of the presence information, which is included in the presence information after update, indicating non-completion of transmission to the posting server is equal to or larger than a predetermined value. 
     According to the above-described printer terminal, the posting sever that has delivered the print content to the printer terminal can assuredly acquire that the print content data has been delivered to the printer terminal, and printing of the print content in the printer terminal has been completed. 
     The above-described printer terminal may further include a data deleting unit that deletes the contents data stored in the memory unit. In the case, the communication unit transmits the presence information after update to the posting server when the state of the contents data that is included in the presence information is updated so as to indicate the completion of deletion. 
     In such a case, the posting server that has delivered the print content to the printer terminal can assuredly acquire that the print contents data has been deleted in the printer terminal. 
     In the above-described printer terminal, the communication unit may be configured to retry transmission for the posting server at a predetermined interval when there is the presence information after update of which the transmission for the posting server has not been completed. 
     In such a case, the presence information that has not been transmitted can be assuredly transmitted to the posting server. 
     In the above-described printer terminal, the signaling protocol may be configured to be an SIP (Session Initiation Protocol). 
     In the above-described printer terminal, the data transmission protocol may be configured to be an HTTP (Hypertext Transfer Protocol) or an HTTPS (Hypertext Transfer Protocol Security). 
     According to a second aspect of the invention, there is provided a posting server that delivers contents data for printing a content to a printer terminal and allows the printer terminal to perform printing based on the contents data. The posting server includes: a reception unit that receives the contents data and delivery destination information that are transmitted from the transmission terminal; a delivery unit that delivers the contents data, which has been received by the reception unit, based on a predetermined data transmission protocol by using a session that has been set up between the posting server and the printer terminal represented by the delivery destination information, which has been received by the reception unit, by using a relay server based on a signaling protocol; an acquisition unit that acquires presence information representing the delivery state and the printing state of the contents data, which have been delivered by the delivery unit, from the printer terminal of the delivery destination; and a providing unit that provides the transmission terminal with the presence information that has been acquired by the acquisition unit. 
     According to the above-described posting server, the posting server can provide the transmission terminal whether the print content data requested by the transmission terminal has been delivered to the printer terminal, and the print content has been printed by using the printer terminal. 
     In the above-described posting server, the delivery unit may be configured to deliver the contents data as a push type. 
     In addition, in the above-described posting server, the signaling protocol may be configured to be an SIP (Session Initiation Protocol). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements. 
         FIG. 1  is a schematic block diagram showing the configuration of a content delivery system as a first embodiment of the invention. 
         FIG. 2  is a block diagram showing a major configuration of a posting server. 
         FIG. 3  is a block diagram showing a major configuration of SIP servers. 
         FIG. 4  is an explanatory diagram showing the types of general SIP servers. 
         FIG. 5  is an explanatory diagram showing various forms of the configuration of printer terminals. 
         FIG. 6  is an explanatory diagram showing the sequence of the process for setting up a session between a posting server and a printer terminal. 
         FIG. 7  is a block diagram showing a major configuration of the printer terminal. 
         FIG. 8  is a diagram showing an example of the data structure of presence information. 
         FIG. 9  is a flowchart showing the process of the printer terminal for receiving contents data. 
         FIG. 10  is a flowchart showing a process for updating the presence information and a process for transmitting the presence information. 
         FIG. 11  is a flowchart showing a detailed process for transmitting a record for the presence information. 
         FIG. 12  is a sequence diagram schematically showing exchange of major data from delivery of a print content to delivery display. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, a content delivery system according to an embodiment of the invention will be described with reference to the accompanying drawings. 
       FIG. 1  is a schematic block diagram showing the configuration of the content delivery system according to this embodiment. 
     As shown in  FIG. 1 , the content delivery system according to this embodiment is configured by a transmission terminal  112 S that is managed by a company that desires to deliver print contents (an advertisement, a text for distance learning, or the like), a posting server  102  and SIP (session initiation protocol) servers  104  and  106  that are managed by a network service provider, and printer terminals  108 P and  110 P that are managed by clients. The posting server  102  and the SIP servers  104  and  106  may be managed by different network service providers or a same network service provider. In addition, the posting server  102 , the SIP servers  104  and  106 , and the printer terminals  108 P and  110 P are interconnected through a so-called broadband network  114  including the Internet. The transmission terminal  112 S may be connected to the posting server  102  through the same broadband network or may be connected to the posting server  102  through a dedicated line or the like. 
     In addition, as shown in  FIG. 1 , within the network  114 , it is assumed that the posting server  102 , the SIP server  104 , and the printer terminal  108 P belong to the domain of “west.com”, and the SIP server  106  and the printer terminal  110 P belong to the domain of “east.com”. 
     In this embodiment, the print contents such as advertisement or a text for distance learning, to be described in detail later, is transmitted from the transmission terminal  112 S to the posting server  102  as contents data and is delivered to the printer terminals  108 P and  110 P by the posting server  102  as a PUSH type. Here, as the contents data that is used for such a printing process, various types of data such as JPEG data, GIF data, PNG data, TIFF data, plain-text data, HTML data, PDF data, or PostScript (registered trademark) data that can be used for representing an image or a document can be used. In addition, when the model of the printer or the like that is used as the printer terminal is known, the contents data may be configured to be delivered in the format of print data. Here, the “PUSH type” means a method of delivering information in which the server side unilaterally transmits the information so as to be delivered to the terminal even when the terminal side does not request the information. In this embodiment, to be described later, the contents data is transmitted by using HTTP or HTTPS. Thus, two methods including a so-called push-type delivery method in which data is transmitted by accessing the printer terminals  108 P and  110 P from the posting server  102  (HTTP POST) and a so-called pull-type delivery method in which data is acquired by accessing the posting server  102  from the printer terminals  108 P and  110 P (HTTP GET) can be used. 
       FIG. 2  is a block diagram showing a major configuration of the posting server  102  shown in  FIG. 1 . As shown in  FIG. 2 , the posting server  102  is configured by a server computer. The posting server  102  includes a CPU  10  that performs various processes and control operations by executing a program, a communication unit  12  that transmits various types of data, information, or the like to another device through a network, and a memory  14  that is used for storing a program, data, or information therein as its basic components. Among these, the memory  14  can store the contents data  16 , delivery request information  18 , or the like therein as data or information. In addition, the posting server  102  includes an input unit such as a keyboard or a pointing device, a display unit such as a monitor, or the like other than the above-described constituent elements, which are not shown in the figure. 
     In addition, in this embodiment, before the above-described delivery of the contents data, the setup of a session between devices is performed by using an SIP (session initiation protocol) that is one type of a signaling protocol. In addition, in this embodiment, an HTTP (hypertext transfer protocol) or an HTTPS (hypertext transfer protocol security), which is one type of a data transmission protocol, other than SIP is configured to be used for delivery of the contents data, that is, transmission of the contents data between devices. Here, a “session” is a relationship for transmitting or receiving media streams between nodes such as terminals. 
       FIG. 3  is a block diagram showing a major configuration of the SIP servers  104  and  106  shown in  FIG. 1 . As shown in  FIG. 3 , the SIP servers  104  and  106 , similarly to the posting server  102 , are configured by a server computer. The SIP servers  104  and  106  include a CPU  30  that performs various processes and control operations by executing a program, a communication unit  32  that transmits various types of data, information, or the like to another device through a network, and a memory  34  that is used for storing a program, data, or information therein as its basic components, respectively. Among these, the memory  34  can store registration information  36 , presence information  38 , or the like to be described later therein as information. In addition, the SIP servers  104  and  106  respectively include an input unit such as a keyboard or a pointing device, a display unit such as a monitor, or the like other than the above-described constituent elements, which are not shown in the figure. 
       FIG. 4  is an explanatory diagram showing the types of general SIP servers. Generally, the SIP servers can be divided into the types shown in  FIG. 4  based on the functions thereof. 
     A registrar accepts a registration request from an SIP client (that is, an SIP user agent) and registers the SIP address (that is, an SIP URI (uniform resource identifier)) or the positional information (that is, an IP (interne protocol) address or the like) of the SIP client in a location server. 
     The location server is a database for storing the SIP address, the positional information, or the like of the SIP client or the SIP server. 
     A proxy server is a server that relays a request or a response between the SIP clients. The proxy server relays session setup or the like between the SIP clients. 
     A redirect server notifies of the positional information of an opponent party desired to be communicated with, in response to an inquiry from the SIP client. 
     A presence server acquires and manages information on the state of the SIP client (for example, whether the power of the SIP client is turned on or off) and provides other SIP clients with the information as presence information. 
       FIG. 5  is an explanatory diagram showing various forms of the configuration of the printer terminals  108 P and  110 P shown in  FIG. 1 . As the configuration of the printer terminals  108 P and  110 P, as shown in  FIG. 5 , various forms may be considered to be used. Here, a multifunction device to be described later is a multiple-functional printing device that includes at least a printing function and a read-out and transmission function. In addition, a printer is a single-function printing device that includes at least a printing function. 
     In the first form, the printer terminal is configured only by an IP (internet protocol) communication printing-supported multifunction device  52 . The IP communication printing-supported multifunction device  52  can directly handle a global address such as an SIP URI, to be described later. Thus, even when being directly connected to the broadband network  114  such as the Internet through the broadband router  50 , the IP communication printing-supported multifunction device  52  can exchange data with devices on the network  114 . Therefore, the printer terminal can be configured only by the IP communication printing-supported multifunction device  52 . The delivered contents data, as denoted by a black arrow  72 , is transmitted from the network  114  to the IP communication printing-supported multifunction device  52  through the broadband router  50 . In addition, instead of the IP communication printing-supported multifunction device, an IP communication printing-supported printer may be configured to be used. 
     In the second faun, the printer terminal is configured by a personal computer  54  and a multifunction device  56  or a printer  58  that is directly connected to the personal computer  54  through a USB cable or the like. The delivered contents data, as denoted by a black arrow  74 , is transmitted to the personal computer  54  through the broadband router  50  so as to be output to the multifunction device  56  or the printer  58 . 
     In the third form, the printer terminal is configured by a personal computer  54  and a network-supported multifunction device  62  that is connected to the personal computer  54  through a LAN (local area network)  70  by using a LAN cable or the like. The network-supported multifunction device  62  cannot handle a global address but a private address. Accordingly, the network-supported multifunction device  62  cannot exchange data with devices on the network  114  without the personal computer  54  or the like interposed therebetween. The transmitted contents data, as denoted by the black arrow  74 , is transmitted to the personal computer  54  through the broadband router  50  and then, as denoted by a black arrow  76 , is transmitted to the network-supported multifunction device  62  through the LAN  70 . In addition, instead of the network-supported multifunction device, a network-supported printer may be configured to be used. 
     In the fourth form, the printer terminal is configured by a personal computer  54 , a network adaptor  64  that is connected to the personal computer  54  through a LAN  70  by using a LAN cable or the like, and a multifunction device  66  or a printer  68  that is connected to the network adaptor  64  by using a USB cable or the like. This form is effective when the multifunction device or the printer is not network-supported. The transmitted contents data, as denoted by a black arrow  74 , is transmitted to the personal computer  54  through the broadband router  50  and then, as denoted by a black arrow  78 , is transmitted to the network adaptor  64  through the LAN  70 . Thereafter, the content data is output to the multifunction device  66  or the printer  68 . 
     Here, instead of being connected together by using a wire such as a cable, the devices may be connected wirelessly by using a wireless LAN, Bluetooth, an infrared ray, or the like. 
     While a global IP address can be assigned on the network  114  including the Internet, a private IP address can be assigned on many private networks such as the LAN  70 . In such a case, there is a so-called NAT (network address translation) traversal problem. However, as generally known, such a problem can be solved by using UPnP (Universal Plug and Play) technology, STUN (Simple Traversal of UDP through NAT) technology, TURN (Traversal Using Relay NAT) technology, ICE (Interactive Connectivity Establishment) technology, or the like as an NAT traversing method. 
     The multifunction device has the read-out and transmission function, as described above. Thus, when the multifunction device is used, the multifunction device may configure not only the printer terminal but also a transmission terminal. Alternatively, a form in which the transmission terminal is configured by a personal computer  54  and a scanner  60  that is directly connected to the personal computer  54  by using a USB cable or the like may be considered to be used. When the transmission terminal is configured, the read-out and transmitted contents data is transmitted to the network  114  following a path formed in a direction opposite to the above-described black arrow. The SIP servers  104  and  106  in this embodiment correspond to a relay server according to an embodiment of the invention. 
     In this embodiment, as described above, the setup of a session between devices is performed by using the SIP that is one type of the signaling protocol, and transmission of the contents data between the devices is performed by using the HTTPS that is one type of the data transmission protocol. Hereinafter, the overview of the operation of the contents delivery system in this embodiment will be described. 
     As shown in  FIG. 1 , first, when getting started, the posting server  102  and the printer terminal  108 P access the SIP server  104  that belongs to the same domain (west.com) as SIP clients. Similarly, when getting started, the printer terminal  110 P also accesses the SIP server  106  that belongs to the same domain (east.com) as an SIP client. Then, the positing server  102  and the printer terminals  108 P and  110 P, as denoted by broken arrows  116 ,  118 , and  120 , output registration requests to the accessed SIP servers  104  and  106  and transmit information such as the SIP URI or the IP address thereof. The SIP servers  104  and  106  serve as registrars and location servers, and, as shown in  FIG. 3 , the CPU  30  accepts the registration request through the communication unit  32  and registers the transmitted information in the memory  34  as the registration information  36 . 
     As a result, the SIP sever  104  has the registration information on the posting server  102  and the printer terminal  108 P that belong to the same domain (west.com) as that of the SIP server  104 , and the SIP server  106  has the registration information of the printer terminal  110 P that belongs to the same domain (east.com) as that of the SIP sever  106 . In the registration information  36 , the SIP URI and the IP address are associated with each other for each terminal, and the registration information  36  is managed by the CPU  30 . 
     Here, for example, the SIP URI is denoted by an identifier in the format of “sip:user@west.com”. In the format, at the beginning, an identifier (scheme) that indicates a SIP is placed (“sip”). Next, a user identifier is placed (“user”), and a host name is placed (“west.com”) with being demarcated by “@”. In addition, as the user identifier, a user ID, a telephone number, or the like is used. As the host name, an FQDN (Fully Qualified Domain Name) or an IP address is used. Furthermore, a port number, an option parameter, or the like may be configured to be placed after the host name. In addition, instead of the SIP URI, an SIPS URI that is a secured URI of the SIP may be used. In such a case, “sips” is placed as the scheme. 
     When a prior preparation process for the SIP is completed as described above, delivery of the contents data can be performed by using the SIP. 
     First, the entity data of one or more print contents desired to be delivered as the print contents and the list of delivery destinations are prepared on the company side. The transmission terminal  112 S transmits the contents data that includes one entity data or more and delivery request information that includes the list of the delivery destinations to the positing server  102  as denoted by a white arrow  138 . The posting server  102  temporarily stores the received contents data  16  and the delivery request information  18  in the memory  14 , as shown in  FIG. 2 . At this moment, API (Application Program Interface) technology is used for transmission of the contents data and the delivery request information from the transmission terminal  112 S to the posting server  102 . As the transmission protocol, the HTTPS is used. However, a different data transmission protocol such as an FTP (File Transfer Protocol) may be configured to be used as the transmission protocol. 
     The CPU  10  of the posting server  102  reads out the delivery request information  18  and analyzes the list of the delivery destinations included therein. In the list of the delivery destinations, the SIP URI of the printer terminal  108 P or  110 P is written as the delivery destination. Then, the CPU  10  of the posting server  102 , first, transmits a request to the SIP server  104  that belongs to the same domain (west.com) as that of the posting server  102  with the printer terminal  110 P designated as a delivery destination based on the list of the delivery destinations (a solid-line arrow  122 ). At this moment, the SIP server  104  serves as a proxy server. Since the printer terminal  110 P belongs to the domain (east.com) that is different from that of the SIP server  104 , the SIP server  104  does not have the registration information on the printer terminal  110 P. Thus, the SIP server  104  transmits the request to the SIP server  106  that belongs to the same domain (east.com) as that of the printer terminal  110  (a solid-line arrow  126 ). The SIP server  106  also serves as a proxy server. Since the printer terminal  110 P belongs to the same domain (east.com) as that of the SIP server  106 , the SIP server  106  has the registration information on the printer terminal  110 P. Accordingly, the SIP server  106  relays the transmitted request to the printer terminal  110 P based on the registration information (a solid-line arrow  128 ). The printer terminal  110 P transmits the response for the request to the SIP server  106  with the posting server  102  designated as a reply destination (a solid-line arrow  132 ). Then, since the posting server  102  belongs to the domain (west.com) that is different from that of the SIP server  106 , the SIP server  106  does not have the registration information on the posting server  102 . Accordingly, the SIP server  106  transmits the response to the SIP server  104  that belongs to the same domain (west.com) as that of the posting server  102  (a solid-line arrow  134 ). Since the posting server  102  belongs to the same domain (west.com) as that of the SIP server  104 , the SIP server  104  has the registration information on the posting server  102 . Accordingly, the SIP server  104  relays the transmitted response to the posting server  102  based on the registration information (a solid-line arrow  136 ). As described above, by exchanging the request and the response between the posting server  102  and the printer terminal  110 P, a session between both parties is set up. At this moment, both the SIP servers  104  and  106  relay the setup of the session by serving as proxy servers. Described in more details, the request and the response as shown in  FIG. 6  are exchanged. 
       FIG. 6  is an explanatory diagram showing the sequence of the process for setting up a session between the posting server  102  and the printer terminal  110 P shown in  FIG. 1 . In  FIG. 6 , time flows from the upper side to the lower side. In addition, the process sequence advances in the order of the numbers enclosed with brackets. 
     The posting server  102 , in order to deliver its IP address to the printer terminal  110 P, has the IP address of the posting server  102  to be included in the body of an INVITE request message that is to be transmitted to the printer terminal  110 P. Meanwhile, the printer terminal  110 P, in order to deliver its IP address to the posting server  102 , also has the IP address of the printer terminal  110 P to be included in the body of a 200 OK response message that is to be transmitted to the posting server  102 . 
     Accordingly, when an ACK request message that has been transmitted from the posting server  102  reaches the printer terminal  110 , the session between the posting server  102  and the printer terminal  110 P is set up. 
     Thereafter, the posting server  102  directly accesses the printer terminal  110 P without being mediated by the SIP servers  104  and  106  based on the IP address of the printer terminal  110 P that has been acquired from the 200 OK response message and delivers the contents data through HTTPS as the PUSH type, as denoted by the white arrow  142  shown in  FIG. 1 . 
     When completing receiving the delivered contents data, the printer terminal  110 P transmits a BYE request message to the posting server  102  through the SIP servers  104  and  106  in accordance with the SIP. When receiving the BYE request message, the posting server  102  returns the 200 OK response message to the printer terminal  110 P through the SIP servers  104  and  106 . Accordingly, the session formed between the posting server  102  and the printer terminal  110 P is cleared. 
     Next, the CPU  10  of the posting server  102  transmits a request to the SIP server  104  with the printer terminal  108 P that belongs to the same domain (west.com) as that of the posting server  102  designated as a delivery destination based on the list of the delivery destinations (a solid-line arrow  122 ). Since the printer terminal  108 P belongs to the same domain (west.com) as that of the SIP server  104 , the SIP server  104  has the registration information on the printer terminal  108 P. Accordingly, the SIP server  104  relays the request to the printer terminal  108 P based on the registration information (a solid-line arrow  124 ). The printer terminal  108 P transmits the response for the request to the SIP server  104  with the posting server  102  designated as the reply destination (a solid-line arrow  130 ). Then, since the posting server  102  belongs to the same domain (west.com) as that of the SIP server  104 , the SIP server  104  has the registration information on the posting server  102 . Accordingly, the SIP server  104  relays the response to the posting server  102  based on the registration information (a solid-line arrow  136 ). As described above, by exchanging the request and the response between the posting server  102  and the printer terminal  108 P, a session between both parties is set up. At this moment, the SIP server  104  relays the setup of the session by serving as a proxy server. In addition, since the sequence of the process for setting up a session between the posting server  102  and the printer terminal  108 P can be easily acquired on the analogy of the above-described  FIG. 6 , a description thereof is omitted here. 
     When the session between the posting server  102  and the printer terminal  108 P is set up as described above, the posting server  102  directly accesses the printer terminal  108 P without being mediated by the SIP server  104  based on the IP address of the printer terminal  108 P and delivers the contents data through HTTPS as the PUSH type, as denoted by the white arrow  140  shown in  FIG. 1 . 
     When the delivery of the contents data is completed, the posting server  102  and the printer terminal  108 P exchange a BYE request message and a 200 OK response message. Accordingly, the session formed between the posting server  102  and the printer terminal  108 P is cleared. 
     The printer terminals  108 P and  110 P perform printing by using the printing function based on the delivered contents data, whereby outputting the print contents. Accordingly, the print contents can be delivered to clients who manage the printer terminals  108 P and  110 P. 
     On the other hand, the SIP servers  104  and  106  serve as presence servers. The CPU  30  of the SIP server  104  acquires the presence information on the state of the printer terminal  108 P belonging to the same domain (west.com) through the communication unit  32 , and the CPU  30  of the SIP server  106  acquires the information on the state of the printer terminal  110 P belonging to the same domain (east.com) through the communication unit  32 . Then, as shown in  FIG. 3 , the CPUs  30  of the SIP servers  104  and  106  store the acquired presence information in the memory  34  as presence information  38  and manage the presence information  38 . The presence information  38  on the printer terminals  108 P and  110 P that belong to the domains of the SIP servers  104  and  106  may be configured to be exchanged between the SIP servers  104  and  106 . Then, the CPUs  30  of the SIP servers  104  and  106  provide the posting server  102  the presence information  38 . Accordingly, the posting server  102  can acquire the states of the printer terminals  108 P and  110 P. 
     According to the above-described embodiment, the network  114  that includes the Internet is used for transmission of the contents data. Accordingly, the contents data can be delivered at a low cost and a high speed. In addition, since a client&#39;s high-performance printer or multifunction device can be used as the printer terminal, high-quality printing can be performed. Furthermore, by using the posting server  102 , the company side only needs to prepare the contents data desired to be delivered as the print content and the list of the delivery destinations, whereby the required human resources and economic costs are decreased. In addition, by using the posting server  102 , a large amount of the print content can be delivered. Furthermore, as the posting server  102  delivers the contents data as the PUSH type, the client can automatically receive the print content without awareness of anything. 
       FIG. 7  is a block diagram showing a major configuration of the printer terminal  110 P. Here, although the printer terminal  110 P is described as an example, the printer terminal  108  may also have the same configuration as the printer terminal  110 P. In  FIG. 7 , the printer terminal  110 P is described as a multifunction device such as the IP communication printing-supported multifunction device  52  or the network-supported multifunction device  62  that can be directly connected to the network as an example. However, even when the printer terminal  110 P is configured by the multifunction device  66  or the printer  68  that is connected to the network through the network adaptor  64  or is configured by the personal computer  54 , the printer  58 , the multifunction device  56 , or the like, the same configuration can be substantially implemented. 
     The printer terminal  110 P includes a CPU  310  that performs various processes and control operations by executing programs, a communication unit  320  that performs transmission of various types of data, information, or the like to other devices through a network, a memory  330  that is used for storing a program, data, or information therein, and a print engine  340  that includes a print head, a paper feed mechanism, and the like and performs printing, as its basic components. Among these, the memory  330  can store the contents data  16  delivered from the posting server  102  and the presence information  38  of the contents data  16  therein. In addition, a transmission queue  335  is arranged on the memory  330 . 
     Furthermore, the printer terminal  110 P includes an input-output unit such as an operation panel other than the above-described constituent elements, which is not shown in the figure. 
     The communication unit  320  accepts a session setup request from the posting server  102  through the SIP servers  106  and  104  and sets up a session between the posting server  102  and the printer terminal. In addition, the communication unit  320  acquires the contents data  16  (data entity  160 ) through the HTTP or the HTTPS from the posting server  102  by using the set up session and stores the contents data in the memory  330 . 
     The contents data  16  is configured by a plurality of data entities  160 ,  160 , . . . corresponding to individual print contents. 
     The presence information  38  includes information that represents the attributes of each data entity  160 ,  160 , . . . . For example, in the presence information  38 , as shown in  FIG. 8 , a document number  381  that is identification information of each data entity  160 ,  160 , . . . , a SIP URI  382  that is identification information of the posting server  102  of the transmission source, a contents operating state  383  that represents the state of each data entity  160 ,  160 , . . . and a contents printing state  384  that represents the printing state of each data entity  160 ,  160 , . . . are included as data items. In the presence information  38 , one record  380  is configured for one data entity  160 . In other words, in the presence information  38 , a plurality of records  380 ,  380 , . . . corresponding to a plurality of data entities  160 ,  160 , . . . is included. 
     For example, the contents operating state  383  may take a “reception-completed state” that indicates completion of the reception (delivery) of the data entity  160 , a “printing-completed state” that indicates completion of printing, a “deletion-completed state” that indicates the completion of deletion of the data entity  160  from the memory  330 , and the like. In addition, the contents printing state  383 , for example, may take “normal completion” that indicates that the printing has been normally completed, “cancel” that indicates that the printing has been canceled in the middle of the process by a user, an “abnormal completion” indicates that the printing has not been normally completed due to an error of the printer or the like, and the like. 
     When the CPU  310  executes predetermined programs, a management unit that manages the presence information  38 , a deletion unit that deletes the data entity  160  from the memory  330 , and the like are implemented. For example when the communication unit  320  stores the received data entity  160  in the memory  330 , the CPU  310 , serving as the management unit, updates the contents operating state  383  of the record  380  for the presence information  38  corresponding to the data entity  160  to the “reception-completed state”. In addition, when the print engine  340  performs printing based on the data entity  160 , the CPU  310  serving as the management unit acquires the status of the printing from the print engine  340  and updates the record  380  for the presence information  38  corresponding to the printed data entity  160 . For example, when printing of a specific data entity  160  is normally completed, the contents operating state  383  of the record  380  corresponding to the presence information  38  is updated to the “printing-completed state”, and the contents printing state  383  is updated to the “normal completion”. On the other hand, when the CPU  310  serving as the deletion unit deletes the data entity  160  from the memory  330 , the CPU  310  serving as the management unit updates the contents operating state  383  of the record  380  for the presence information  38  corresponding to the deleted data entity  160  to the “deletion-completed state” in accordance with the deletion. 
     For example, the CPU  310  serving as the deletion unit may be configured to delete the data entity  160  from the memory  330  when receiving a direction from a user. Alternatively, it may be configured that an effective period from the delivery time is set for each data entity  160  in advance, and the CPU  310  serving as the deletion unit automatically deletes each data entity  160  when the effective period of the data entity  160  elapses. 
     When any item of the record  380  in which the presence information  38  is included is updated, the CPU  310  serving as the management unit stores the record  380 , in which the presence information  38  after update is included, in the transmission queue  335 . For example, the CPU  310  may be configured to store the record  380 , in which the presence information  38  after update is included, in the transmission queue  335  in a case where the contents operating state  383  is updated, particularly where the contents operating state  383  becomes the “reception-completed state”, the “printing-completed state”, or the “deletion-completed state”. 
     The communication unit  320  tries to transmit the record  380  for the presence information  38  that is stored in the transmission queue  335  to the posting server  102 . The communication unit  320  may be configured to transmit the record  380  for the presence information  38 , for example, by using the TCP or the UDP. The posting server  102  located at the delivery destination, for example, is determined based on the SIP URI  382  of the presence server  102  that is included in the transmitted record  380  for the presence information  38 . When transmission of the record  380  for the presence information  38  to the posting server  102  cannot be completed for some reason or other, the communication unit  320  waits for a predetermined time and then retries the transmission of the record  380  for the presence information  38  that remains in the transmission queue  335 . After a complete transmission of the record  380  of the presence information  38  to the presence server  120 , the record is deleted from the transmission queue  335 . The determination on whether the transmission has been completed, for example, may be configured to be performed based on whether the notification of reception of the record  380  for the presence information  38  has been received from the posting server  102 . 
     In a case where the records  380  for the presence information  38  equal to or more than a predetermined number are accumulated in the transmission queue  335 , even when there is a new session setup request from the presence server  102 , the communication unit  320  denies the request. There is need to assuredly transmit the record  380  for the presence information  38  to the presence server  102 . Accordingly, when the record  380  for the presence information  38  that has not been transmitted is increased, a new data entity  160  is not accepted. 
     Next, the process of the printer terminal  110 P having the above-described configuration will be described with reference to a flowchart. 
       FIG. 9  is a flowchart showing the process of the printer terminal  110 P for receiving the contents data  16 . 
     First, the communication unit  320  accepts a session setup request from the posting server  102  through the SIP servers  104  and  106  (S 100 ). Here, the communication unit  320  determines whether the session setup request can be accepted (S 110 ). For example, in a case where the session setup request is not to be accepted (S 110 : No) such as a case where the records  380  for the presence information  38 , which have not been transmitted, equal to or more than the predetermined number are stored in the transmission queue  335 , the communication unit  320  denies the session setup request (S 180 ). 
     On the other hand, in a case where the session setup request is accepted by the communication unit  320  (S 110 : Yes), the communication unit  320  performs a predetermined session setup process between the posting server  102  and the printer terminal  110 P (S 120 ). Then, when the session is set up between the printer terminal  110 P and the posting server  102  (S 130 : Yes), the communication unit  320  receives the data entity  160  of the contents data  16  transmitted from the posting server  102  by using the HTTPS (S 140 ). 
     As described above, when the records  380  for the presence information  38 , which have not transmitted, equal to or more than the predetermined number are stored in the transmission queue  335 , the printer terminal  110 P denies the session setup request from the posting server  102 . Accordingly, it can be prevented that the records  380  for the presence information  38 , which have not been transmitted, are increased too much in the posting server  102 , whereby a trouble such as a loss of a record that has not been transmitted is prevented in advance. 
     Next,  FIG. 10  is a flowchart showing a process for updating the presence information and a process for transmitting the presence information. 
     When detecting the state change in the data entity  160 , the CPU  310  updates the record  380  for the presence information  38  corresponding to the data entity  160  (S 200 ). For example, when the record  380  for the presence information  38  is updated as the data entity  160  delivered from the posting server  102  is received or printing on the basis of the data entity  160  is completed, the CPU  310  detects the update of the record  380  for the presence information  38 . 
     Then, the CPU  310  reads out the updated record  380  for the presence information  38  from the memory  330  and stores the updated record  380  in the transmission queue  335  (S 210 ). 
     When the record  380  for the presence information  38  is stored in the transmission queue  335 , the communication unit  320  transmits the record  380  for the presence information  38  that is stored in the transmission queue  335  (S 220 ). Accordingly, the updated record  380  for the presence information  38  is immediately started to be transmitted to the posting server  102 . This transmission process will be described in detail as below. 
       FIG. 11  is a flowchart showing a detailed process for transmitting the record  380  for the presence information  38 . 
     The communication unit  320  determines whether one or more records  380  for the presence information  38  that have not been transmitted is stored in the transmission queue  335  (S 300 ). When there is no record  380  for the presence information  38 , which have not been transmitted, in the transmission queue  335  (S 300 : No), the communication unit  320  completes this process. 
     On the other hand, when there are the records  380  for the presence information  38 , which have not been transmitted, in the transmission queue  335  (S 300 : Yes), the communication unit  320  tries to transmit the records  380  for the presence information  38 , which have not been transmitted, to the posting server  102  sequentially from the beginning of the transmission queue  335  (S 310 ): 
     After performing the above-described transmission, the communication unit  320  determines whether the transmission of the records to the posting server  102  has been successful (S 320 ). 
     When the transmission of the record  380  for the presence information  38  to the posting server  102  has been successful (S 320 : Yes), the communication unit  320  deletes the transmission-completed records  380  from the transmission queue  335  (S 330 ). On the other hand, when the transmission of the record  380  for the presence information  38  has failed (S 330 : No), the communication unit  320  waits for a predetermined time and repeats Step S 310  and the following processes thereof (S 340 ). 
     Accordingly, the record  380  for the presence information  38  that is accumulated in the transmission queue can be transmitted to the posting server  102 . 
     Next,  FIG. 12  is a sequence diagram schematically showing exchange of major data until delivery display for checking whether a print content is delivered and printed is performed after the delivery of the print content is requested by a transmission terminal  112 S. The exchange of data will now be described with reference to the figure. In the figure, the SIP servers  104  and  106 , the process for setting up a session, and the like are omitted. 
     First, the request terminal  112 S transmits the data entity  160  and delivery request information of the print content to the posting server  102  (S 400 ). The communication unit  12  of the posting server  102  receives the contents data and the delivery request information. 
     The posting server  102  determines a printer terminal  110 P, which is the delivery destination, based on the delivery request information and the communication unit  12  delivers the contents data to the printer terminal  110 P through the SIP servers  104  and  106  by using a setup session (S 410 ). 
     When receiving the data entity  160 , as described above, the printer terminal  110 P transmits the record  380  for the presence information  38  corresponding to the data entity  160  to the posting server  102  (S 430 ). The communication unit  12  of the posting server  102  acquires the record  380  for the presence information  38  that has been transmitted from the printer terminal  110 P. 
     The posting server  102  provides the transmission terminal  112 S delivery result information that represents the completion of delivery of the data entity  160  based on the record  380  for the presence information  38  that is acquired by the communication unit  12  (S 440 ). Then, the transmission terminal  112 S performs delivery display that represents the status of the content requested to be printed based on the provided delivery result information. Accordingly, it can be acquired that the print content requested to be delivered by the transmission terminal  112 S has been delivered to the printer terminal  110 P. 
     Meanwhile, the printer terminal  110 P prints the received data entity  160 . Then, when completing the printing, the printer terminal  110 P transmits the record  380  for the presence information  38  corresponding to the data entity  160  to the posting server  102  (S 450 ). The communication unit  12  of the posting server  102  acquires the record  380  for the presence information  38  that has been transmitted from the printer terminal  110 P. 
     The posting server  102  provides the transmission terminal  112 S the delivery result information representing completion of printing the data entity  160  based on the record  380  for the presence information  38  that is acquired by the communication unit  12  (S 460 ). Then, the transmission terminal  112 S performs the delivery display based on the provided delivery result information. Accordingly, it can be acquired that the print content requested to be transmitted by the transmission terminal  112 S has been printed by using the printer terminal  110 P. 
     In addition, when the data entity  160  is deleted, the printer terminal  110 P transmits the record  380  for the presence information  38  corresponding to the data entity  160  to the posting server  102  (S 470 ). The communication unit  12  of the posting server  102  acquires the record  380  for the presence information  38  that has been transmitted by the printer terminal  110 P. 
     The posting server  102  provides the transmission terminal  112 S the delivery result information representing the completion of deletion of the data entity  160  based on the record  380  for the presence information  38  that has been acquired by the communication unit  12  (S 480 ). Then, the transmission terminal  112 S performs the delivery display based on the delivery result information. Accordingly, it can be acquired that the print content requested to be delivered by the transmission terminal  112 S has been deleted in the printer terminal  110 P. 
     As described above, by providing the transmission terminal the delivery result information, a company or the like that has requested to deliver the print content can be notified that the print content has been delivered to the printer terminal or the print content has been printed. 
     The above-described embodiment of the invention is an example for describing the invention and is not for the purpose of limiting the scope of the invention to such an embodiment. Those skilled in the art may perform the invention in various forms without departing from the gist of the invention.