Abstract:
Disclosed herein is an information processing apparatus including: a setting section configured to set as a first parameter at least a tolerable maximum latency time representative of a network profile for use within an end point in a network environment; a control section configured to control the transmission of target data by performing real-time control based on the first parameter set by the setting section; a conversion section configured to convert the first parameter into a second parameter for controlling the quality of service on paths of the network; and a transmission section configured to transmit onto the network the target data furnished with the second parameter derived from the conversion by the conversion section.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an information processing apparatus and method, a program, and an information processing system and method. More particularly, the invention relates to an information processing apparatus and method, a program, and an information processing system and method whereby QoS (Quality of Service) related control is provided in real time within each of end points as well as between these end points making up an entire network. 
     2. Description of the Related Art 
       FIG. 1  schematically shows a typical configuration of an ordinary AV (Audio and Video) system. The AV system in  FIG. 1  is made up of pieces of business-use AV equipment such as MPEG IMX (Moving Picture Experts Group IMX) and HDCAM. More specifically, the representative AV system in  FIG. 1  is constituted by such business-use AV devices as a video tape recorder (called simply as the VTR hereunder)  11 , a monitor  12 , another VTR  13 , and a controller  14 . AV data is transferred between these business-use AV devices over cables  21 A through  21 C dedicated to AV data transfer. 
     In addition to the AV data, the AV system of  FIG. 1  has control commands such as RS-422 (9-Pin) commands communicated internally. If a 9-Pin command is issued and a response is not returned within 10 milliseconds, a communication error is recognized because the required levels of real-time performance are very high. The requirements are that certain processes be completed within a predetermined time period (i.e., predetermined time constraints must be met). 
     In order to meet the elevated requirements for real-time performance, the AV system of  FIG. 1  utilizes control command cables  22 A through  22 C apart from the AV data transfer cables  21 A through  21 C. However, these two categories of cables being installed individually have led to problems associated with complicated wiring. 
     Hence the need for transmitting broadband data such as AV data and control commands over a single network cable in mixed fashion. The need is supposed to be met by suitable capabilities to ensure a maximum latency time in sending and receiving data including control commands, a process subject to exacting requirements for real-time performance. 
     To implement such capabilities illustratively involves resorting to Internet-ready priority control and quality support techniques. These techniques include Intserv and Diffserv. Intserv is a technique that envisages securing a frequency band between end points using a protocol called RSVP (Resource Reservation Protocol), thereby guaranteeing certain levels of quality of service (QoS). Intserv has yet to be commercialized because of the complexity of RSVP and other problems related to scalability and implementation of the technique. Diffserv is a technique used by routers on the network to schedule packets in accordance with the value of a DSCP field in an IP (Internet Protocol) header of each packet, thereby achieving a relative QoS guarantee. 
     The techniques outlined above involve control over end-to-end paths, not precedence-based control within an end point. That means it is impossible for these techniques to provide the latency time guarantee required by control commands. 
     An end point in this context refers to a section within a piece of AV equipment with a communication capability. An end-to-end path thus means a path between at least two different end points. 
     The inventors invented a technique for meeting required levels of real-time performance by speeding processes inside each end point. The invention is disclosed in Japanese Patent Laid-Open No. 2007-201884. The disclosed technique involves providing precedence control and frequency band control within each end point. 
     SUMMARY OF THE INVENTION 
     The above-cited technique, however, is limited to what takes place inside the end point. When the technique is applied to an actual system, it is difficult to implement control on network paths, i.e., control over end-to-end paths. 
     The present invention has been made in view of the above circumstances and provides inventive arrangements whereby real-time control such as QoS control is brought about over an entire network, not only within each end point but also between the end points making up the network. 
     In carrying out the present invention and according to one embodiment thereof, there is provided an information processing apparatus including: setting means for setting as a first parameter at least a tolerable maximum latency time representative of a network profile for use within an end point in a network environment; control means for controlling the transmission of target data by performing real-time control based on the first parameter set by the setting means; conversion means for converting the first parameter into a second parameter for controlling the quality of service on paths of the network; and transmission means for transmitting onto the network the target data furnished with the second parameter derived from the conversion by the conversion means. 
     According to another embodiment of the present invention, there is provided an information processing method as well as a program each including the steps corresponding to the operations performed by the component means of the above-outlined information processing apparatus of the invention. 
     Where the information processing apparatus, information processing method, or program outlined above is in use, at least a tolerable maximum latency time is set as a first parameter representative of a network profile for use within an end point in a network environment. The transmission of target data is controlled by performing real-time control based on the first parameter having been set. The first parameter is then converted to a second parameter for controlling the quality of service (QoS) on paths of the network. The target data is transmitted onto the network together with the second parameter derived from the conversion. 
     According to a further embodiment of the present invention, there is provided an information processing apparatus including: reception means for receiving target data transmitted together with a second parameter derived through conversion from a first parameter set at least as a tolerable maximum latency time representative of a network profile for use within an end point other than the end point constituted by the information processing apparatus in a network environment, the second parameter being intended for control of the quality of service on paths of the network; conversion means for converting into the first parameter the second parameter attached to the target data received by the reception means; and control means for controlling the reception of the target data by the reception means by performing real-time control based on the first parameter derived from the conversion by the conversion means. 
     According to an even further embodiment of the present invention, there is provided an information processing method as well as a program each including the steps corresponding to the operations performed by the component means of the information processing apparatus of the invention outlined above. The steps involve: receiving target data transmitted together with a second parameter derived through conversion from a first parameter set at least as a tolerable maximum latency time representative of a network profile for use within an end point other than the end point constituted by the information processing apparatus in a network environment, the second parameter being intended for control of the quality of service (QoS) on paths of the network; converting into the first parameter the second parameter attached to the target data received in the receiving step; and controlling the reception of the target data in the receiving step by performing real-time control based on the first parameter derived from the conversion in the converting step. 
     According to a still further embodiment of the present invention, there is provided an information processing system including a first end point and a second end point in a network environment. In the system, the first end point in the network environment sets at least a tolerable maximum latency time as a first parameter representative of a network profile for use within the end points; the first end point further controlling the transmission of target data by performing real-time control based on the first parameter; the first end point further converting the first parameter into a second parameter for control of the quality of service (QoS) on paths of the network; the first end point further transmitting onto the network the target data furnished with the second parameter derived from the conversion. And, in the system, the second end point in the network environment receives the target data from the first end point over the network; the second end point further converting into the first parameter the second parameter attached to the target data having been received; and the second end point further controlling the reception of the target data by performing real-time control based on the first parameter derived from the conversion. 
     According to a yet further embodiment of the present invention, there is provided an information processing method including the steps corresponding to the operations performed by the components of the above-outlined information processing system of the invention. 
     Where the above-outlined information processing system or information processing method corresponding thereto is in use, the first end point in the network environment sets at least a tolerable maximum latency time as a first parameter representative of a network profile for use within the end points. The first end point further controls the transmission of target data by performing real-time control based on the first parameter. The first end point further converts the first parameter into a second parameter for control of the quality of service on paths of the network. The first end point further transmits onto the network the target data furnished with the second parameter derived from the conversion. The second end point in the network environment receives the target data from the first end point over the network. The second end point further converts into the first parameter the second parameter attached to the target data having been received. The second end point further controls the reception of the target data by performing real-time control based on the first parameter derived from the conversion. 
     The present invention, as outlined above, makes it possible to implement real-time control within each of the end points making up a network. In particular, the invention permits real-time control such as QoS control over the entire network, not only within each end point but also between the end points making up the network. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features and advantages of the present invention will become apparent upon a reading of the following description and appended drawings in which: 
         FIG. 1  is a block diagram showing a typical configuration of an ordinary transmission/reception system; 
         FIG. 2  is a block diagram showing a typical configuration of a transmission/reception system embodying the present invention; 
         FIG. 3  is a block diagram showing a typical hardware structure of a communication device as part of the system in  FIG. 2 , the device serving as an information processing apparatus embodying the present invention; 
         FIG. 4  is a block diagram showing a detailed hardware structure of a communication unit as part of the communication device in  FIG. 3 ; 
         FIG. 5  is a functional block diagram showing a typical functional structure of the communication unit in  FIG. 4 ; 
         FIG. 6  is a tabular view showing a profile table held by a profile parameter holding section in  FIG. 5 ; 
         FIG. 7  is a flowchart of steps in which the communication unit of  FIG. 5  functions typically as a transmission unit; 
         FIG. 8  is a tabular view pairing data IDs with profile numbers; 
         FIGS. 9A and 9B  are schematic views showing typical structures of Ethernet frame headers; 
         FIG. 10  is a schematic view showing a typical structure of an IP header; and 
         FIG. 11  is a flowchart of steps in which the communication unit of  FIG. 5  functions typically as a reception unit. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The preferred embodiments of the present invention will now be described in reference to the accompanying drawings. 
       FIG. 2  schematically shows a typical configuration of an AV system acting as an information processing system embodying the present invention. 
     For purpose of comparison with the ordinary AV system shown in  FIG. 1 , the AV system of  FIG. 2  is shown made up of pieces of business-use AV equipment such as a VTR  31 - 1 , a monitor  31 - 2 , a VTR  31 - 3 , and a controller  31 - 4 . These pieces of business-use AV equipment are collectively referred to as a communication device  31 . AV data and control commands can be transferred between the components of the communication device  31  by means of one type of cables  41 A through  41 D via a switch  35 . Why and how the transfer of AV data and control commands is made possible will be discussed later by referring to  FIGS. 5 through 11 . 
       FIG. 3  schematically shows a typical hardware structure of the communication device  31 . 
     In the communication device  31  of  FIG. 3 , a CPU (Central Processing Unit)  41  performs various processes using the programs held in a ROM (Read Only Memory)  42  or those loaded from a recording unit  48  into a RAM (Random Access Memory)  43 . The RAM  43  may also accommodate data needed by the CPU  41  in carrying out diverse processing. 
     The CPU  41 , ROM  42 , and RAM  43  are interconnected by way of a bus  44 . An input/output interface  45  is also connected to the bus  44 . 
     The input/output interface  45  is further connected with an input unit  46 , an output unit  47 , a recording unit  48 , and a communication unit  49 . The input unit  46  is typically made up of a keyboard and a mouse. The output unit  47  is generally composed of speakers and a display such as LCD (Liquid Crystal Display). The recording unit  48  is formed by a hard disk drive or the like. 
     The communication unit  49  is formed illustratively by an NIC (Network Interface Card) that controls communications with other blocks over a network. Details of the communication unit  49  will be discussed later. The type of network is not limited to anything specific. In the example of  FIG. 2 , the switch  35  and cables  41 A through  41 D constitute a network that interconnects the components of the communication device  31 . 
     A drive  50  may be connected as needed to the input/output interface  45 . A piece of removable media  51  such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory may be loaded into the drive  50 . Computer programs read by the drive  50  from the loaded removable medium  51  are installed as needed into the recording unit  48 . 
     The hardware structure of the communication device  31  is not limited to what is depicted in  FIG. 3 , as is evident from the typical structure of the communication device  31  illustrated in  FIG. 2 . It should be noted that each of the components making up the communication device  31  has at least a specific functional structure to be discussed later in reference to  FIG. 5 . 
       FIG. 4  schematically shows a detailed hardware structure of the communication unit  49 . 
     The communication unit  49 , connected to the input/output interface  45  ( FIG. 2 ), transmits the data coming from the CPU  41  ( FIG. 2 ) to another communication device  31  over the network to which the latter is connected. The communication unit  49  also receives data from the other communication device  31  on the network and feeds the received data to the CPU  41 . In addition, the communication unit  49  may perform protocol stack processing (predetermined processes related to protocol stacks) illustratively under TCP/IP (Transmission Control Protocol/Internet Protocol). 
     The communication unit  49  is structured to include a CPU  61 , a ROM  62 , a RAM  63 , a recording part  65 , an interface  66 , and a transmission/reception processing part  67 . The CPU  61 , ROM  62 , RAM  63 , recording part  65 , interface  66 , and transmission/reception processing part  67  are interconnected via a bus  64 . 
     In the communication unit  49  of  FIG. 4 , the CPU  61  performs various processes using the programs held in the ROM  62  or those loaded from the recording part  65  into the RAM  63 . The RAM  63  may also accommodate data needed by the CPU  61  in carrying out diverse processing. 
     Illustratively, the transmission/reception processing part  67  under control of the CPU  61  performs predetermined processing to transmit data to another communication device  31  over the network to which the latter is connected, or to receive data from the other communication device  31  on the network. 
     The hardware structure of the communication unit  49  is not limited to what is shown in  FIG. 4 . In hardware terms, the communication unit  49  need only have at least part of the functional structure to be discussed later in reference to  FIG. 5 . 
       FIG. 5  schematically shows a typical functional structure made up of part of the functions possessed by the communication device  31  of which the hardware structure is shown in  FIGS. 3 and 4 . The functional structure of  FIG. 5  is needed to implement the capability of communicating with another communication device  31  via the network. 
     In the example of  FIG. 5 , the communication device  31  is structured to include a network application execution section  102  and the communication unit  49 . In the structure of  FIG. 5 , only the network application execution section  102  is furnished outside the communication unit  49 . The other functional sections ranging from an interface section  104  to a profile parameter holding section  119  are contained within the communication unit  49 . 
     In other words, in the example of  FIG. 5 , solely the network application execution section  102  runs on application software under control of the operating system executed by the CPU  41  ( FIG. 3 ). The other components ranging from the interface section  104  to the profile parameter holding section  119  function under control of the CPU  61  of the communication unit  49  ( FIG. 4 ). 
     The individual functions (workings) of the functional blocks shown in  FIG. 5 , to be explained later by referring to  FIGS. 5 through 11 , are thus not described here. 
     In an information processing system (e.g., AV system of  FIG. 2 ) including the communication device  31  having the functional structure such as one shown in  FIG. 5 , the network application software of the communication device  31  includes the capability of setting RTPs (Real Time Parameters) for use in conducting communications. The network application software is executed by the network application execution section  102 . 
     The RTPs (Real Time Parameters) are parameters representative of network properties for use by the communication device  31  in transmitting and receiving data at an end point (i.e., end device such as the communication unit  49  shown in  FIGS. 3 through 5 ) in a network environment. The network properties illustratively include a precedence level, a frequency range for use, and a tolerable maximum latency time. 
     With the embodiment of this invention, a plurality of data items sharing the same network properties (RTPs such as the precedence level and frequency range) are handled as a single entity called a profile. 
     In this context, the communication device  31  working as an end device on the network can perform real-time control (precedence control and frequency band control) on a profile-by-profile basis. 
     The communication device  31  has a correspondence table that lists profiles in association with QoS control parameters for the network paths of TOS, Diffserv, VLAN, etc. This table is called a profile table. 
     Based on the profile table, the communication device  31  may attach suitable QoS control parameters to outgoing packets destined for the network paths of TOS, Diffserv, VLAN, etc. 
     Also based on the profile table, the communication device  31  may determine the profile to be used for real-time control within the device  31  upon receipt of an incoming packet together with the QoS control parameters attached thereto, i.e., parameters for the network paths of TOS, Diffserv, VLAN, etc. 
     How the profile table is established will now be described. 
     The network application executed by the network application execution section  102  (the application is interpreted simply as the workings of the section  102  hereunder) sets RTPs (precedence level, frequency range, maximum latency time) for use within the communication device  31  in conjunction with QoS control parameters for the network paths of TOS, Diffserv, VLAN, etc. on a profile-by-profile basis, to the profile parameter holding section  119  by way of the interface section  104 . 
     Given the parameters thus established, the profile parameter holding section  119  updates and holds the profile table. 
       FIG. 6  shows a typical profile table held by the profile parameter holding section  119 . The profile table in  FIG. 6  includes major items “profile numbers,” “RTPs used inside the communication device  31 ,” and “QoS control parameters for network paths.” Subsumed under the item “RTPs used inside the communication device  31 ” are subordinate items “precedence level,” “frequency range,” and “maximum latency time.” Under the item “QoS control parameters for network paths” come subordinate items “DSCP,” “VLAN user priority,” and “TOS value.” Each row in the profile table of  FIG. 6  contains the values of the above-mentioned items for a single profile. 
     Described below in reference to  FIG. 7  is how the communication device  31  functions as a transmission device performing a transmitting process, with the above-described profile table held in the profile parameter holding section  119 . 
     In step S 1 , the network application execution section  102  sets the IDs and profile numbers of transmit data to the profile parameter holding section  119  through the interface section  104 . The transmit data refers to the target data to be transmitted. In the description that follows, it is assumed that the transmit target data is selected from the transmit data to which the IDs and profile numbers have been set in step S 1 . 
     In step S 2 , the profile parameter holding section  119  updates a pair table that pairs the established IDs with the corresponding profile numbers.  FIG. 8  shows a typical pair table in which data IDs are listed in conjunction with profile numbers. 
     In step S 3 , the network application execution section  102  writes the transmit target data and its ID to the interface section  104 . 
     In step S 4 , a transmit data profile determination section  105  determines the profile of the transmit target data based on the ID of the data and on the pair table held by the profile parameter holding section  119 . 
     In step S 5 , the transmit data profile determination section  105  selects a transmit data queue  107  based on the determined profile. The transmit data queue  107  associates each profile with a memory that temporarily stores the transmit target data. In the example of  FIG. 5 , three memories are shown furnished for the transmit data queue  107  with regard to three profiles in the profile table of  FIG. 6 . Of the three memories, one that corresponds to the determined profile (i.e., one of profiles Nos.  1  through  3  in  FIG. 6 ) is selected. This is what actually takes place when the transmit data queue  107  is selected. 
     In step S 6 , the transmit data profile determination section  105  stores the transmit target data temporarily in the selected transmit data queue  107 . What actually takes place in this step is that the transmit target data is placed temporarily into one of the three memories which corresponds to the determined profile (i.e., one of profile Nos.  1  through  3  in  FIG. 6 ). 
     In step S 7 , a real-time control section  118  switches processes of a network processing section  109  based on the parameters of the profile table held by the profile parameter holding section  119 . 
     In step S 8 , the network processing section  109  acquires the transmit target data from the transmit data queue  107 , performs socket processing and network protocol processing to create network packets, and sets the packets to a transmit packet queue  110 . 
     The network processing section  109  has profile network processing blocks  109 - 1  through  109 - 3 . 
     The profile network processing block  109 - 1  addresses one of the three memories of the transmit data queue  107 , i.e., the memory corresponding to the profile with profile No.  1  in  FIG. 6 . The profile network processing block  109 - 1  carries out socket processing and network protocol processing on the transmit target data placed in the memory being addressed, using as RTPs the items under the major item “RTPs used inside the communication device  31 ” corresponding to the profile with profile No.  1 . This creates network packets that are set in the transmit packet queue  110 . 
     The profile network processing block  109 - 2  addresses another one of the three memories of the transmit data queue  107 , i.e., the memory corresponding to the profile with profile No.  2  in  FIG. 6 . The profile network processing block  109 - 2  carries out socket processing and network protocol processing on the transmit target data placed in the memory being addressed, using as RTPs the items under the major item “RTPs used inside the communication device  31 ” corresponding to the profile with profile No.  2 . This creates network packets that are set in the transmit packet queue  110 . 
     The profile network processing block  109 - 3  addresses another one of the three memories of the transmit data queue  107 , i.e., the memory corresponding to the profile with profile No.  3  in  FIG. 6 . The profile network processing block  109 - 3  carries out socket processing and network protocol processing on the transmit target data placed in the memory being addressed, using as RTPs the items under the major item “RTPs used inside the communication device  31 ” corresponding to the profile with profile No.  3 . This creates network packets that are set in the transmit packet queue  110 . 
     The transmit packet queue  110  has a memory furnished corresponding to each of different profiles. These memories are intended temporarily to retain network packets. In keeping with three profiles in the profile table of  FIG. 6 , the setup of  FIG. 5  has three memories provided for the transmit packet queue  110 . One of the three memories is set temporarily with network packets created by the profile network processing block  109 - k  (k is an integer of 1 through 3) that corresponds to the profile (with profile No. k in  FIG. 6 ) associated with the memory in question. This is what actually takes places when network packets are set in the transmit packet queue  110 . 
     Based on the parameters in the profile table held by the profile parameter holding section  119 , the real-time control section  118  effects control in a manner switching the profile network processing blocks  109 - 1  through  109 - 3  as needed. This provides precedence control, latency guarantee control, and frequency band control on the transmit data. 
     In step S 9 , a transmit packet precedence control section  112  fetches transmit packets from the transmit packet queue  110  in descending order of precedence levels in the profile table held by the profile parameter holding section  119 . The fetched transmit packets are handed over to a transmit packet parameter replacement section  114 . 
     In step S 10 , based on the “QoS control parameters for network paths” in the profile table held by the profile parameter holding section  119 , the transmit packet parameter replacement section  114  replaces the TOS/Diffserv field value in the IP header and adds a VLAN tag to the Ethernet frame header in the header of each transmit packet. 
     That is, a VLAN tag-furnished Ethernet frame header shown in  FIG. 9B  is created from the ordinary Ethernet frame header indicated in  FIG. 9A  in step S 10 . 
     The ordinary Ethernet header in  FIG. 9A  is constituted, from left to right, by a six-byte “Destination MAC Address” field, a six-byte “Source MAC Address” field, and a four-byte “Type” field. 
     The VLAN tag-furnished Ethernet frame header in  FIG. 9B , on the other hand, is supplemented with a four-byte “VLAN Tag” field inserted between the “Source MAC Address” field and the “Type” field of the ordinary Ethernet frame header in  FIG. 9A . 
     The “VLAN Tag” field is constituted, from left to right, by a two-byte “Tag ID” field, a three-bit “User Priority” field, a one-bit “CF” field, and a 12-bit “VLAN ID” field. Into the “User Priority” field is placed the value of the item “VLAN user priority” that comes under the item “QoS control parameters for network paths” in the profile table held by the profile parameter holding section  119 . 
     The IP header is a header structured as shown in  FIG. 10 . Into the third field “TOS/DSCP” from left (i.e., TOS/Diffserv field) is placed the value of the item “VLAN user priority” that comes under the item “QoS control parameters for network paths” in the profile table held by the profile parameter holding section  119 . 
     The transmit packets furnished with the QoS control parameters in the manner described above are transferred from the transmit packet parameter replacement section  114  to a packet transmission section  115 . At this point, control is passed from step S 10  to step S 11 . 
     In step S 11 , the packet transmission section  115  transmits the packets supplemented with the QoS control parameters onto the network through a MAC (Media Access Control address) section  117 . 
     This step completes the transmitting process outlined in  FIG. 7 . 
     Each packet transmitted by the transmitting process shown in  FIG. 7  is received by another communication device  31  over the network. The communication unit  49  of the receiving communication device  31  then functions as a reception unit that carries out a receiving process such as one outlined in the flowchart of  FIG. 11 . The receiving process is performed by the communication device  31  acting as a reception device, with the profile table held by the profile parameter holding section  119 . 
     In step S 21 , a packet reception section  116  checks whether any packet is received. If no packet is found to be received (“No” in step S 21 ), then control is returned to step S 21  and the check is repeated. In other words, the check in step S 21  is repeated until any packet is found to be received by the packed reception section  116  from the network through the MAC section  117 , with the receiving side remaining in a wait state as indicated in  FIG. 11 . 
     Upon receipt of a packet by the packet reception section  116  from the network by way of the MAC section  117 , the result of the check in step S 21  becomes affirmative (“Yes”) and step S 22  is reached. In step S 22 , the received packet is forwarded from the packet reception section  116  to a received packet profile determination section  113 . 
     In step S 22 , the received packet profile determination section  113  determines the profile of the received packet based on the profile table held by the profile parameter holding section  119 , using the TOS/Diffserv field value and the VLAN tag precedence (VLAN user priority level) in the IP header of the received packet. The profile thus determined is supplied to a received packet precedence control section  120 . Control is then passed on to step S 23 . 
     In step S 23 , the received packet precedence control section  120  selects a received packet queue  111  based on the determined profile. In step S 24 , the received packet precedence control section  120  temporarily stores the received packet selected. 
     The received packet queue  111  has a memory furnished for each of the profiles involved, the memories being intended to accommodate received packets temporarily. In the example of  FIG. 5 , three memories are shown furnished for the received packet queue  111  in keeping with the three types of profiles listed in the profile table of  FIG. 6 . When the profile determined in step S 22  turns out to be one with profile No. “k” in  FIG. 6 , the memory corresponding to the profile with profile No. “k” is selected. This is what actually takes place when the received packet queue  111  is selected. Performing step S 24  involves temporarily placing the received packet into the memory associated with the profile having profile No. “k.” 
     In step S 25 , the real-time control section  118  switches processes of the network processing section  109  based on the parameters in the profile table held by the profile parameter holding section  119 . 
     In step S 26 , the network processing section  109  acquires the received packet from the received packet queue  111 , performs network protocol processing and socket processing to obtain received data, and sets the data thus obtained to a received data queue  108 . 
     The network processing section  109  has the profile network processing blocks  109 - 1  through  109 - 3  as mentioned above. 
     The profile network processing block  109 - 1  address one of the three memories of the received packet queue  111 , the addressed memory being associated with the profile with profile No.  1  in  FIG. 6 . The profile network processing block  109 - 1  performs socket processing and network protocol processing on the received packet placed in the memory being addressed, using as RTPs the subordinate item values under the item “RTPs used inside the communication device  31 ” corresponding to the profile with profile No.  1  in  FIG. 6 . The profile network processing block  109 - 1  temporarily places the received data thus obtained into the received data queue  108 . 
     The profile network processing block  109 - 2  address another one of the three memories of the received packet queue  111 , the addressed memory being associated with the profile with profile No.  2  in  FIG. 6 . The profile network processing block  109 - 2  performs socket processing and network protocol processing on the received packet placed in the memory being addressed, using as RTPs the subordinate item values under the item “RTPs used inside the communication device  31 ” corresponding to the profile with profile No.  2  in  FIG. 6 . The profile network processing block  109 - 2  temporarily places the received data thus obtained into the received data queue  108 . 
     The profile network processing block  109 - 3  address another one of the three memories of the received packet queue  111 , the addressed memory being associated with the profile with profile No.  3  in  FIG. 6 . The profile network processing block  109 - 3  performs socket processing and network protocol processing on the received packet placed in the memory being addressed, using as RTPs the subordinate item values under the item “RTPs used inside the communication device  31 ” corresponding to the profile with profile No.  3  in  FIG. 6 . The profile network processing block  109 - 3  temporarily places the received data thus obtained into the received data queue  108 . 
     The received data queue  108  is furnished with a memory for each of the profiles involved, the memories being used to store received data temporarily. In the example of  FIG. 5 , three memories are shown furnished for the received data queue  108  in keeping with the three types of profiles listed in the profile table of  FIG. 6 . The received data is placed selectively in one of the three memories for temporary storage, the selected memory being associated with the profile (i.e., one with profile No. “k” in  FIG. 6 ) corresponding to the profile network processing block  109 - k  (k is one of integers 1 through 3). This is what actually takes place when the received data is stored temporarily in the received data queue  108 . 
     The real-time control section  118  switches the profile network processing blocks  109 - 1  through  109 - 3  based on the parameters in the profile table held by the profile parameter holding section  119 . This provides precedence control, latency guarantee control, and frequency band control on the received data in the same manner as on the transmit data. 
     In step S 27 , a received data precedence control section  106  acquires the received data from the received data queue  108  in descending order of the precedence levels in the profile table held by the profile parameter holding section  119 . 
     In step S 28 , the received data precedence control section  106  sends the received data to the network application execution section  102  via the interface section  104 . 
     This step completes the receiving process outlined in  FIG. 11 . 
     As described above, the embodiment of the present invention allows an end point in a network environment such as the Ethernet (registered trademark) to designate RTPs representing the desired network properties (e.g., precedence level, frequency range to be used, tolerable maximum latency time) for use by the user in transmitting and receiving data. The RTPs provide the basis for controlling the timings of data transmission and reception processing. 
     According to the invention, it is thus possible to guarantee the maximum latency time in transmitting and receiving data of high precedence levels inside the end device on the network. 
     Where large quantities of data are being transmitted or received by the end device on the network, the invention makes it possible to send or receive those types of data of which delays or jitters are desired to be minimal, with a minimum of delays or jitters as desired. 
     Inside the end device, the RTP settings can be made to correspond with the QoS control parameters such as TOS/Diffserv and VLAN tag. With such correspondence in effect, these QoS control parameters are attached to each of the packets to be transmitted. The receiving side may then determine the RTPs from the attached precedence settings based on the RTP/QoS control parameter correspondence. 
     As a result, it is possible to implement real-time control (QoS control) over the entire network; such control ranges in scope from an end device to network paths to another end device. 
     In the preceding examples, the RTP settings are made to correspond with the QoS parameters by use of the profile table. However, this arrangement is not limitative of the present invention. Alternatively, the transmit packet parameter replacement section  114  ( FIG. 5 ) or the like may convert the RTP settings to the QoS control parameters or vice versa automatically, i.e., at its own discretion based on predetermined algorithms. 
     During high-speed reception of large quantities of data such as AV data, the inventive arrangements permit reception and execution of the data to be processed on a highly real-time basis such as control commands, with little delay. It is also possible, during high-speed transmission of large quantities of data such as AV data, to transmit with little delay the data that needs to be handled on an appreciably real-time basis such as control commands. 
     With the above-outlined benefits turned into a reality, it is then possible to substitute solely one type of cable for a variety of AV data cables and control command-dedicated cables used in the past. Illustratively, the AV data cables  21 A through  21 C supplemented with the control command cables  22 A through  22 C used in the past as shown in  FIG. 1  can be replaced by the network cables  41 A through  41 D in the inventive setup depicted in  FIG. 2 . 
     The series of the steps and processes (or part of them) described above may be executed either by hardware or by software. 
     Where the software-based processing is to be carried out, the programs constituting the software may be either incorporated beforehand in dedicated hardware of a computer for program execution or installed upon use over a network or from a suitable recording medium into a general-purpose personal computer or like equipment capable of executing diverse functions based on the installed programs. 
     As shown in  FIGS. 3 and 4 , the recording medium is offered to users not only as removable media (package media)  51  apart from their computers and constituted by magnetic disks (including floppy disks), optical disks (including CD-ROM (Compact Disk-Read Only Memory) and DVD (Digital Versatile Disk)), magneto-optical disks (including MD (Mini-Disk)), or a semiconductor memory accommodating the programs of interest; but also in the form of the ROM  42  or  62  in  FIG. 3  or the recording unit  48  or recording part  65  in  FIG. 3  or  4  composed of a hard disk drive, each containing the programs and incorporated beforehand in the users&#39; computers. 
     In this specification, the steps describing the programs stored on the recording medium represent not only the processes that are to be carried out in the depicted sequence (i.e., on a time series basis) but also processes that may be performed parallelly or individually and not chronologically. 
     In this specification, the term “system” refers to an entire configuration made up of a plurality of component devices and processing elements. 
     Although the communication unit  49  in  FIG. 4  was shown to be one component of the communication device  31  in the foregoing description, this is not limitative of the invention. Alternatively, the communication unit  49  may be considered a single independent device as shown in  FIG. 4 . In this case, the communication unit  49  in  FIG. 4  may be removably attached to the communication device  31 . The communication unit  49  may function as an end point attached not only to the communication device  31  but also to a variety of other devices, carrying out diverse processes to conduct network communications as discussed above. 
     The present application contains subject matter related to that disclosed in Japanese Priority Patent Application JP 2008-104497 filed in the Japan Patent Office on Apr. 14, 2008, the entire content of which is hereby incorporated by reference. 
     It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alternations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalent thereof.