Abstract:
A communication system is provided which, upon communication, is capable of making a suitable response by using interpretation execution parts which conform to the background concepts and vocabularies of a conversation. A flexible and smooth information exchange and cooperation are realized among, and between, agents and an existing system by dynamically allocating suitable interpretation execution parts which include an interpreter in conformance to a variety of agent communication languages, content describing languages and ontologies. The agent communication system in a preferred embodiment of this invention is provided with an interpretation execution part control function that scans a directory of interpretation parts such as conversation content monitoring parts, interpreters and translators, upon the time of execution start or during execution, and forms and maintains an interpretation execution part table that defines what interpretation execution parts exist.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a data processing technique, and more particularly, to a technique of dynamically changing processing resources depending on the contents of data to be processed. 
     2. Description of Related Art 
     A human being is usually capable of determining on what topic a conversation is going and how the utterance by a speaker is interpreted during the course of the conversation from the environmental conditions including the situation in which the speaker is placed, experiences in the past, the identity of the speaker and the flow of the conversation. For instance, suppose that a person sitting in a tea room simply tells to a waitress “a coffee”. The waitress would then interpret the statement in a way that the guest agrees to pay the price of a hot coffee listed on a menu placed in the seat and orders a cup of hot coffee poured in a coffee cup. The waitress further recognizes that the order is accepted for the person, and understands that she should take steps of preparing a cup of hot coffee, adding a spoon, sugar and cream to the cup of hot coffee, bringing them to the table of the person and waiting until the person pays the price. 
     However, in a different environmental condition such as where the same statement “a coffee,” is uttered to a shopman in a bookstore, the man would not be able to understand the meaning of the utterance. As exemplified above, data is suitably interpreted even if it contains small amount of information when a statement spoken can be flexibly interpreted taking the situation into consideration. 
     Generally, a “conversation,” between human beings consists of steps in which: 
     1. a speaker prepares a content to be spoken in order to convey the speaker&#39;s intent to a listener; 
     2. the speaker then begins to speak; 
     3. the listener listens to the speech and understands the flow of the conversation; 
     4. the listener associates the speech with the background of the speech from what the listener has experienced; 
     5. the listener understands the content of the speech; 
     and 
     6. the listener takes an action as a result. 
     If a messaging system of a computer is defined as one which simulates the message processing of a natural language and is designed for recycling by patterning a conversation in this way, a message which is closer to a natural language than the prior art can be processed. As a result, an intelligent message system can be constructed which is more user friendly and allows a series of packets having a certain context to be exchanged with the flow of contexts being followed. 
     On the other hand, there is mobile agent technology in the art in which an internal condition is moved to a place which is provided in a server existing on a network in a distributed computer environment to form an instruction in the place where the internal condition is moved. Reference is made to U.S. Pat. No.: 5,603,031, issued Feb. 11, 1997, entitled “System and Method For Distributed Computation Based Upon the Movement, Execution, and Interaction of Processes in a Network”, by White et al., (Japanese unexamined patent publication no.: 7-182174) and Fumihiko Nishida, Susumu Fujiwara et al&#39;s “Latest Internet Technology, special edition of Nikkei Communication”, pp 104-117, Nikkei BP. 
     Mobile agents operating under the mobile agent technology discussed above make a contact to other agents (a mobile agent or a resident agent) in the moved-to place and may be served as appropriate. As referred to herein, a place is a location provided by a server existing on the network to which the agent moved and which supports a contact among agents and absorbs the differences between the hardwares and between the platforms. 
     The mobile agent technology enables a mobile agent to act as a proxy of a human being in handling works such as dynamically adjusting a schedule of internal meetings in compliance with the schedule of attendees and status of reservation of conference rooms and acquiring desired information distributed on the network. 
     However, if in a single place, various types of communications among the agents is supported, a large load is placed on that place, leading to inability of appropriately responding to the content of conversation and extended processing time which is required for the response. Another load is placed to an agent or a software which issues a request when the request for the service becomes complicated due to the support of various types of communications. Further, the communication system is heavily loaded when the amount of data transmitted over the network is increased. When an interpretation execution element which interprets the content of conversation is changed, a problem was encountered in that the system had to be halted temporarily for restart in registration and importation of changed interpretation execution element because the system relied on a single interpretation execution element. 
     There was a prior art system which had a compatible class correlating table for the replacement with a compatible resource to maintain interconnection during the period when the network is upgraded to a new version (Japanese unexamined patent publication no.: PUPA 7-93235). However, such a prior art system which inspected the internal status of the system and replaced resources as a result of inspection was not able to analyze a received message to dynamically change the interpretation execution element which interprets the received message. In addition, such a prior art system had to prepare an alternative resource for the resource in which a change occurred so as to avoid the system from halting, resulting in additional load of the user. 
     In view of the disadvantages of the prior art systems described above, it can be appreciated that it would be desirable to provide a system which overcomes these disadvantages. 
     OBJECTS AND ADVANTAGES OF THE INVENTION 
     It is a first object and advantage of this invention to provide a communication system for processing conversations between agents that overcomes the foregoing and other problems. 
     It is another object and advantage of this invention to provide a communication system which is capable of making a suitable response by means of an analysis execution part in conformance to the content (background concepts or vocabularies) of a conversation among agents. 
     It is a further object and advantage of this invention to provide a message processing system which enables high speed processing by reducing unnecessary decision logic. 
     It is still another object and advantage of this invention to provide a message processing system in which resources required for execution are decreased. 
     It is still a further object of this invention to provide a message processing system which realizes high speed parallel conversation processing. 
     It is still another object of this invention to reduce the work and the time required for developing and maintaining a program as much as possible in providing a support to communication among agents. 
     It is still a further object of this invention to provide a message processing system which is capable of flexibly dealing with conversations among agents. 
     It is still another object of this invention to provide a message processing system which gives less load to a communication network. 
     Further objects and advantages of this invention will become more apparent from a consideration of the drawings and ensuing description. 
     SUMMARY OF THE INVENTION 
     The foregoing and other problems are overcome and the objects of the invention are realized by methods and apparatus in accordance with embodiments of this invention. Disclosed is a technique that enables a flexible and smooth information exchange and coordination among agents and between agents and existing systems by dynamically allocating suitable interpretation execution parts in conformance to an ontology which represents an agent communication language, content describing language and a background concept and vocabulary used in a content. 
     The agent communication system in the preferred embodiment of this invention has an interpretation execution part controlling function which scans a directory of interpretation execution parts including conversation content monitoring parts, interpreters and translators upon start to form and control an interpretation execution part table about what interpretation execution parts are in existence. 
     When a message of a combination of agent communication language, content describing language and an ontology which do not exist in the table is received, the interpretation execution part store directory is scanned to see if the interpretation execution part corresponding thereto has been added. If it has been added, it is added to the table to have it process the message. 
     According to one aspect of this invention, a message processing method is provided for execution by a message processor which has a plurality of different interpreters for processing a message received through the network. The method includes the steps of: receiving a message packet containing an ontology specifying information and a content; selecting one or more interpreters among the plurality of different interpreters in conformance to the ontology specifying information contained in the message packet; and interpreting the content contained in the message packet by means of the selected one or more interpreters. 
     As referred to in this invention, the term “ontology,” includes not only “background concepts and vocabularies,” which are to be described in the preferred embodiment of this invention, but also a concept including all information which squeeze decision results and reduce decision processes in determining the content of transmitted information. 
     According to another aspect of this invention, a message processing method is provided for execution by a message processor which has a plurality of different interpreters for processing a message received through the network. The method includes the steps of: receiving a message packet containing an ontology specifying information, a describing language specifying information and a content specifying information; selecting one or more interpreters among the plurality of different interpreters in conformance to the ontology specifying information and describing language specifying information contained in the message packet; and interpreting a content which corresponds to the content specifying information contained in the message packet by means of the selected one or more interpreters. 
     As referred to herein, the term “content specifying information,” includes not only a content per se, but also link information which points to a content. 
     According to still another aspect of this invention, a message processing method for execution by a message processor which has a plurality of different analysis execution parts. The method includes the steps of: selecting one or more analysis execution parts of the plurality of different analysis execution parts in conformance to the ontology specifying information associated with the content. Further, the method includes interpreting the content by means of the selected one or more analysis execution parts. 
     As referred to herein, the term “analysis execution parts,” is a concept that includes a conversation content monitoring part, an interpreter and a translator which are to be described in the preferred embodiment of this invention. 
     According to a further aspect of this invention, a message processing method is provided for execution by a message processor which has a plurality of different interpreters and an interpreter control table for controlling a plurality of ontology specifying information which correspond to respective ones of the plurality of different interpreters. The method includes the steps of: receiving a message packet containing an ontology specifying information and a content, and determining whether or not an interpreter corresponding to the ontology specifying information contained in the message packet has been registered in the interpreter control table. The method further includes the steps of: determining whether or not the interpreter corresponding to the ontology specifying information is available in the message processor, when it is determined that the ontology specifying information contained in the message packet is not registered in the interpreter control table; registering in the interpreter control table the corresponding interpreter in correspondence to the ontology specifying information contained in the message packet, when it is determined that the interpreter corresponding to the ontology specifying information contained in the message packet is available in the message processor; and interpreting the content contained in the message packet by means of the corresponding interpreter. 
     According to a still further aspect of this invention, a message processing method is provided for execution by a message processor which has a plurality of different interpreters and an analysis execution part control table for controlling a plurality of different analysis execution parts in association with analysis execution part specifying information. The method includes the steps of: 
     receiving a message packet containing an analysis execution part specifying information and a content; and determining whether or not an analysis execution part corresponding to the analysis execution part specifying information contained in the message packet has been registered in the analysis execution part control table. The method further includes the steps of: determining whether or not the analysis execution part corresponding to the analysis execution part specifying information is available in the message processor, when it is determined that the analysis execution part specifying information contained in the message packet is not registered in the analysis execution part control table; and registering in the analysis execution part control table the corresponding analysis execution part in correspondence to the analysis execution part specifying information contained in the message packet, when it is determined that the analysis execution part corresponding to the analysis execution part specifying information contained in the message packet is available in the message processor. 
     According to a further aspect of this invention, a message processor is provided which has a plurality of different interpreters for processing a message received through a network. The processor includes an agent communication language manager for receiving a message packet containing ontology specifying information and a content. The processor also includes an interpreter loader for selecting one or more interpreters among the plurality of different interpreters among the plurality of different interpreters in conformance to the ontology specifying information contained in the message packet. 
     According to a still further aspect of this invention, a message processor is provided which has a plurality of different interpreters for processing a message received through a network. The processor includes an agent communication language manager for receiving a message packet containing an ontology specifying information, a describing language specifying information and a content specifying information. The processor further includes an interpreter loader for selecting one or more interpreters among the plurality of different interpreters in conformance to the ontology specifying information and describing language specifying information contained in said message packet. 
     According to a still further aspect of this invention, a message processor having a plurality of different analysis execution parts is provided which selects one or more analysis execution parts among the plurality of analysis execution parts in conformance to the ontology specifying information associated with the content to interpret the content by means of the selected one or more analysis execution parts. 
     According to a further aspect of this invention, a message processor is provided which has a plurality of different interpreters including an interpreter loader and an interpreter control table for controlling a plurality of ontology specifying information which correspond to respective ones of the plurality of different interpreters. The processor operates to determine whether or not an interpreter corresponding to the ontology specifying information contained in the message packet has been registered in the interpreter control table, the message packet containing an ontology specifying information and a content. The processor further determines whether or not the interpreter corresponding to the ontology specifying information is available in the message processor, when it is determined that the ontology specifying information contained in the message packet is not registered in the interpreter control table. Also, the processor registers in the interpreter control table the corresponding interpreter in correspondence to the ontology specifying information contained in the message packet, when it is determined that the interpreter corresponding to the ontology specifying information contained in the message packet is available in the message processor. 
     According to a still further aspect of this invention, a message processing method is provided for execution by a message processor which has a plurality of different interpreters including an interpreter loader and an analysis execution part control table for controlling a plurality of analysis execution parts in association with analysis execution part specifying information. The method includes the steps of: determining whether or not an analysis execution part corresponding to the analysis execution part specifying information contained in the message packet has been registered in the analysis execution part control table, the message packet containing an analysis execution part specifying information and a content; and determining whether or not the analysis execution part corresponding to the analysis execution part specifying information is available in the message processor, when it is determined that the analysis execution part specifying information contained in the message packet is not registered in the analysis execution part control table. The method further includes the step of registering in the analysis execution part control table the corresponding analysis execution part in correspondence to the analysis execution part specifying information contained in the message packet, when it is determined that the analysis execution part corresponding to the analysis execution part specifying information contained in the message packet is available in the message processor. 
     According to a further aspect of this invention, a message processor is provided which has a plurality of different interpreters for processing a message received through a network. The processor includes an agent communication language manager for receiving a message packet containing ontology specifying information, a describing language specifying information, a content specifying information and a response ID; and a conversation thread control part for analyzing a response ID contained in the message packet to form a conversation thread. The processor further includes a message log for recording the message packet; and an interpreter loader for selecting one or more interpreters among the plurality of different interpreters in conformance to the ontology specifying information and describing language specifying information contained in the message packet. 
     According to one of the aspects of this invention, a recording media is provided which stores therein a message processing program for execution by a message processor which has a plurality of different interpreters for processing a message received through the network. The media includes: a program code which instructs the message processor to receive a message packet containing an ontology specifying information and a content; and a program code which instructs the message processor to select one or more interpreters among the plurality of different interpreters in conformance to the ontology specifying information contained in the message packet. The media further includes a program code which instructs the message processor to interpret the content contained in the message packet by means of the selected one or more interpreters. 
     According to a further aspect of this invention, a media is provided which stores therein a message processing program for execution by a message processor which has a plurality of different interpreters for processing a message received through the network. The media includes: a program code which instructs the message processor to receive a message packet containing an ontology specifying information, a describing language specifying information and a content specifying information; and a program code which instructs the message processor to select one or more interpreters among the plurality of different interpreters in conformance to the ontology specifying information and describing language specifying information contained in the message packet. The media further includes a program code which instructs the message processor to interpret a content which corresponds to the content specifying information contained in the message packet by means of the selected one or more interpreters. 
     According to a still further aspect of this invention, a media is provided which stores therein a message processing program for execution by a message processor which has a plurality of different analysis execution parts. The media includes a program code which instructs the message processor to select one or more analysis execution parts among the plurality of different analysis execution parts in conformance to the ontology specifying information associated with the content. Also, the media includes a program code which instructs the message processor to interpret the content by means of the selected one or more analysis execution parts. 
     According to a further aspect of this invention, a media is provided which stores therein a message processing program for execution by a message processor which has a plurality of different interpreters and an interpreter control table for controlling a plurality of ontology specifying information which correspond to respective ones of the plurality of different interpreters. The media includes: a program code which instructs the message processor to receive a message packet containing an ontology specifying information and a content; a program code which instructs the message processor to determine whether or not an interpreter corresponding to the ontology specifying information contained in the message packet has been registered in the interpreter control table; and a program code which instructs the message processor to determine whether or not the interpreter corresponding to the ontology specifying information is available in the message processor, when it is determined that the ontology specifying information contained in the message packet is not registered in the interpreter control table. The media also includes: a program code which instructs the message processor to register in the interpreter control table the corresponding interpreter in correspondence to the ontology specifying information contained in the message packet, when it is determined that the interpreter corresponding to the ontology specifying information contained in the message packet is available in the message processor; and a program code which instructs the message processor to interpret the content contained in the message packet by means of corresponding interpreter. 
     According to a still further aspect of this invention, a medium is provided which stores therein a message processing program for execution by a message processor which has a plurality of different interpreters and an analysis execution part control table for controlling a plurality of different analysis execution parts in association with analysis execution part specifying information. The media includes a program code which instructs the message processor to receive a message packet containing an analysis execution part specifying information and a content. The media further includes a program code which instructs the message processor to determine whether or not an analysis execution part corresponding to the analysis execution part specifying information contained in the message packet has been registered in the analysis execution part control table. Additionally, the media includes a program code which instructs the message processor to determine whether or not the analysis execution part corresponding to the analysis execution part specifying information is available in the message processor, when it is determined that the analysis execution part specifying information contained in the message packet is not registered in the analysis execution part control table. Further, the media includes a program code which instructs the message processor to register in the analysis execution part control table the corresponding analysis execution part in correspondence to the analysis execution part specifying information contained in the message packet, when it is determined that the analysis execution part corresponding to the analysis execution part specifying information contained in the message packet is available in the message processor. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above set forth and other features of the invention are made more apparent in the ensuing Detailed Description of the Invention when read in conjunction with the attached Drawings, wherein: 
     FIG. 1 shows a distributed network environment in which a mobile agent operates in accordance with the present invention; 
     FIG. 2 is a block diagram showing one embodiment of the hardware configuration of the client system or the server system in accordance with the present invention; 
     FIG. 3 is a block diagram of one embodiment of processing components in the client site or the server site of this invention; 
     FIG. 4 is a schematic diagram of a message packet of this invention; 
     FIG. 5 is a block diagram of one embodiment of processing components in the client (or server) site of this invention; 
     FIG. 6 is an object interaction diagram among the components in a preferred embodiment of this invention; 
     FIG. 7 is a schematic diagram illustrating a conversation content monitoring part control table in a preferred embodiment of this invention; 
     FIG. 8 is a block diagram of one embodiment of processing components in the server (or client) site of this invention; 
     FIG. 9 is an object interaction diagram among the components in a preferred embodiment of this invention; 
     FIG. 10 is a schematic diagram illustrating an interpreter control table in a preferred embodiment of this invention; 
     FIG. 11 is a schematic diagram illustrating a translator control table in a preferred embodiment of this invention; 
     FIG. 12 is a block diagram of one embodiment of processing components in the client (or server) site of this invention; 
     FIG. 13 is a block diagram of one embodiment of processing components in the server (or client) site of this invention; and 
     FIG. 14 is a flow chart showing an embodiment of processing steps taken when the agent communication system of this invention is moved over the network. 
     Identically labelled elements appearing in different ones of the above described figures refer to the same elements but may not be referenced in the description for all figures. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The embodiment of this invention will now be described with reference to the drawings. With reference to FIG. 1, a distributed network environment  150  is shown which executes mobile objects of this invention. Each server  112 - 115  is provided with a place  102 - 105  for serving the mobile agents  125 ,  135 ,  141 , etc. The group of places in the distributed network environment is referred to as a crowd. 
     An application  116  for forming and moving a mobile agent is in a client system  101 . Mobile agents, such as agent  125  which are sent out by the application  116  may get in contact with other agents (mobile or resident agents) existing in each place  102 - 105  (an agent which gets in contact with a mobile agent to provide a service is referred to as an actor agent), send a request and receive the result of the request. A place provides a support to the contact between agents. Mobile agents, such as agent  125  may hold the result of the request received from the actor agent, continue to move, or send the result to the client  101  or other place during movement. 
     The mobile agent  125  (or a resident agent) may send a message packet to another place and execute a conversation and an instruction in such another place. 
     FIG. 2 schematically shows a hardware configuration of each node (a server or a client site) existing on the distributed network environment  150  shown in FIG.  1 . Each node  100  has a central processing unit (CPU)  1  and a memory  4 . The CPU  1  and the memory  4  are connected, via a bus  2 , to a hard disk drive (HDD)  13  acting as an auxiliary storage. Storage media drives including a floppy disk drive (FDD)  20 , the hard disk drives  13  and  30 , CD-ROM drives  26  and  29 , and MO drive  28  are connected to the bus  2  through controllers including a floppy disk controller (FDC)  19 , an IDE controller  25  and a small computer system interface (SCSI) controller  27 . 
     A portable storage media such as a floppy disk is inserted to the storage media drive such as the floppy disk drive  20 . Such floppy disk and other storage media of the hard disk drive  13  and a ROM  14  may have recorded therein a computer program which provides instructions to the CPU  1  in cooperation with an operating system to practice this invention, with the program being loaded into the memory  4 . The computer software may be compressed or divided into multiple modules for storage in multiple media. 
     The node system  100  may be a system which has a user interface hardwired, such as a pointing device (e.g., a mouse  7  and a joy stick, etc.) or a keyboard  6  for input and a display  12  for presenting a visual data to a user. A parallel port  16  may be provided for connecting a printer. The node system  100  may have a modem connected thereto via a serial port  15  for connection to the network through the serial port  15  and the modem or through a token ring or a communication adapter  18  to communicate with other computer systems. 
     It will be readily understood that this invention may be implemented in a conventional personal computer (PC), a workstation, a general purpose computer or a combination of them. It should be noted however that these components are chosen as exemplary components and that not all of the components are necessarily an indispensable component of the invention. Specifically, it is not necessary to install a user interface in the server side because the server can be remote-controlled so that it is enough to have a basic data processing function such as a CPU and a memory, and a communication function. It is enough for the client side to have a configuration that is needed to send out a message packet (described later), including a communication function and an input means for designating a message packet and for transmitting the message packet. 
     The operating system in the client side and the server side may be implemented by one which supports on a standard basis a graphical user interface (GUI) multi-windows environment such as, for example, WindowsNT (trademark of Microsoft), Windows95 (trademark of Microsoft), Windows3.x (trademark of Microsoft), OS/2 (trademark of IBM), X-Window system (trademark of MIT) on AIX (trademark of IBM), and Solaris (trademark of Sun Micro Systems), as well as one which is for character base environment such as PC-DOS (trademark of IBM) and MS-DOS (trademark of Microsoft), and a real time operating system (OS) such as OS/Open (trademark of IBM) and VxWorks (trademark of Wind River Systems, Inc.) without being limited to any specific operating system environment. 
     An overview of an exemplary system configuration suitable for practicing the present invention will now be described. 
     With reference to the block diagram of FIG. 3, a system configuration of the server side in the preferred embodiment of this invention is described. An agent  201  is either a mobile agent which was sent to this server, or a resident agent which is resident in this server. The agent  201  may have a dialog with an agent communication system  200  by transmitting or receiving a message packet which will be described later. 
     An agent communication language manager  203  is a component of the agent communication system  200  for receiving a message sent from the agent  201  or the existing system and network. The agent communication language manager  203  also transmits messages to these systems. 
     A conversation thread control part  205  is a component of the agent communication system  200  for controlling a thread that corresponds to each conversation with an agent, for example agent  201 . The conversation thread control part  205  forms a suitable thread in conformance to the flow of conversation, or gives control to the thread which has been generated. Multiple conversations are spit into multi-threads to accept multiple conversations asynchronously. The thread is hereinafter referred to as a conversation thread  207 . 
     A message log  211  is another component of the agent communication system  200  for memorizing conversations. A conversation monitoring part  217  is also a component of the agent communication system  200  which conducts a policy check as to whether or not a conversation is valid from a conversation log stored in the message log  211  and a content of the current message. A conversation content monitoring part loader  215  is another component of the agent communication system  200  for calling the conversation monitoring part  217  which corresponds to the message type of the message packet  300 . 
     The agent communication system  200  also includes a translator  221  for translating the agent communication language used in the conversation into another language. The agent communication system  200  further includes a translator loader  219  which controls the group of translators. 
     The agent communication system  200  also includes an interpreter  225  for understanding and executing the content of a conversation. A plurality of different such interpreters are provided corresponding to ontologies and describing languages which will be described later. Each interpreter has a format check routine, a content interpretation routine and an execution routine specific to an ontology. For example, an ontology of traffic reservation assumes that a content “R, flight, Narita to Tacoma, 1997/07/06/15:00-1997/07/06/18:00,” is received. After a check for a predetermined format, a specific content interpretation routine is executed. The content interpretation routine interprets that “R,” is a command which invokes a process to make a reservation by accessing a database in a given airline to execute an execution routine for checking the reservation status. Finally, a reservation is made for a non-smoking seat, economy, FlightXX26 for Tacoma, Seattle, departing Narita air port at 17:10 on Jul. 6, 1997 and the reservation is confirmed to the sender. 
     An interpreter loader  223  is also a component of the agent communication system  200  for controlling the group of interpreters  225 . A protocol manager  230  is a component for converting to a protocol which conforms to the type of network to be connected. 
     Each of the functional blocks in FIG. 3 has been described. These functional blocks, or components, are logical functional blocks and are not meant to be implemented as an independent integral hardware or software, but may be implemented as a complex of hardwares and softwares or common hardwares and softwares. Further, not all of the functional blocks in FIG. 3 are necessarily a component which is indispensable to this invention. 
     For example, it would be enough to install either one of the conversation content monitoring part loader  215 , the translator loader  219  and the interpreter loader  223 , to dynamically switch among the conversation content monitoring part  217 , the translator  221  and the interpreter  225  for indicating the interpretation execution part to the used. The agent communication language manager  203 , the conversation thread control part  205 , the conversation thread  207 , the message log  211 , the ID generator  213 , the conversation content monitoring part  217 , the translator  221  and the interpreter  225  are not a component indispensable to one aspect of this invention. 
     An overview of an exemplary operational process suitable for practicing the present invention will now be described. 
     FIG. 4 shows schematically a message packet  300  as used in a preferred embodiment of this invention. FIG. 5 shows an operational condition of each component in FIG. 3 when a message is generated. 
     In a message type  301  contained in the message packet  300  in FIG. 4, a performative of the agent communication language (ACL) is used in the preferred embodiment of this invention. The ACL is a high-level language which provides a communication among agents in a form that is representative of the human language, and includes, for example ACLs provided by FIPA (Foundation for Intelligent Physical Agents), ACL, KQML (Knowledge Query Manipulation Language), and KIF (knowledge Interchange Format. A description of the KQML may be found in “SEMANTICS FOR AN AGENT COMMUNICATION LANGUAGE”, by Yannis Labrou, a Doctoral Dissertation for a PhD Defense Examination, submitted to Defense Committee at the Computer Science and Electrical Engineering Department (CSEE) of the University of Maryland Graduate School and “TR CS- 97 - 03 , A Proposal for a new KQML Specification”, by Yannis Labrou and Tim Finin, Feb. 3, 1997. Included in the performative of KQML which is one of the ACLs are; 
     ask-if, ask-all, stream-all, eos, tell, untell, deny, insert, uninsert, delete-one, delete-all, undelete, achieve, unachieve, advertise, unadvertise, subscribe, error, sorry, standby, ready, next, rest, discard, register, unregister, forward, broadcast, transport-address, broker-one, broker-all, recommend-one, recommend-all, recruit-one, recruit-all. 
     The message packet  300  of FIG. 4 further includes a sender  303  which is a sender of a message, and a receiver  305  which is a receiver of a message. A response ID  307  is an ID which follows a preceding conversation. When an agent has a conversation with a plurality of parties, a plurality of response ID&#39;s  307  are allocated corresponding to the conversation threads which will be described later. A conversation ID  309  is an ID which tells the conversation partner to respond with this ID. The describing language type  311  is information which specifies the language describing the content. The ontology  313  is information which specifies the ontology that the content specifies. 
     The content  315  is the particular content of a message, i.e. the subject or topic covered by the message, and includes a software for forming instructions after it moved to another place in the preferred embodiment of this invention. The content  315  may also internally contain a message packet for movement to another place via a relaying point. The content may also include a “from,” entry and a “to,” entry which indicate a true sender and a final receiver, respectively, in the preferred embodiment of this invention. 
     An operational condition of each component in FIG. 3 during message generation will now be described with reference to FIG.  5 . The agent  201  sends a message packet  300 , shown in FIG. 4, to the agent communication system  200 . 
     In the preferred embodiment of this invention, the components shown in FIG. 3 are defined as a class of an object orientated programming language. As hereinafter referred to, a class is a set of objects within the object oriented programming language methodology that contain the same types of values and the same methods. Similarly, a method refers to procedures within an object that operate to, for example, send messages to other objects. 
     Each object, upon generating a message, prompts other objects to operate by sending an instruction to such other objects as shown in the object instruction diagram among components in FIG.  6 . The agent communication language manager  203 , upon receiving the message packet  300 , conducts a message generation process when it is called with a “sendMessage” method, while it conducts a receive message process when it is called with a “handleMessage,” method. 
     The conversation thread control part  205  determines with reference to the response ID  307  which is contained in the message packet  300  whether or not to ask an already generated conversation thread to process. If the conversation thread control part  205  determines that it is a new conversation, it generates a new conversation thread  207 , instructs the ID generator  213  via the conversation thread  207  to allocate a new conversation ID  309  and moves the control to the conversation thread  207 . In the preferred embodiment of this invention, the conversation ID  307  is allocated with an ID which is uniquely identified on the network, such as “URL+Date+Time+Serial Number”. 
     If a conversation thread  207  corresponding to the response ID  307  has existed, the conversation thread control part  205  determines that this is not a new conversation and moves the control to the corresponding conversation thread  207 . If it is desired to continue the conversation, the conversation thread  207  instructs the ID generator  213  to allocate conversation ID  309 . The message log  211  then memorizes the message packet  300  which is sent to the conversation thread  207 . 
     The conversation content monitoring part loader  215  calls a conversation content monitoring part  217  corresponding to the message type  301  of the message packet  300 . The conversation content monitoring part  217  corresponding to the message type  301  may be called by providing a conversation content monitoring part table  330  as shown in FIG. 7, or by using a class name of the conversation content monitoring part  217  which is the same as the message type  301 . 
     The conversation content monitoring part  217  conducts a policy check as to whether or not a conversation could be valid based on the conversation log stored in the message log  211  and the content of the current message. For example, if the message type  301  of the received message packet  300  is “sorry” (a message type which means that the content of the conversation is understandable but the receiving party does not have a capability to process), a reference is made to the message log  211  for a message type  301  of the message which has a corresponding response ID  307  and an immediately preceding ID. It is then determined that the message type  301  can be processed if it is of a type which is valid as a conversation, for example an “ask-if,” (a message type  301  which queries about the processing capability of the other party). However, if the message type  301  is determined to be of a message type  301  which can not be valid as a conversation like, for example, “deny” (a message type  301  which means denial), then an action is taken such as, for example, sending a message packet  300  of “error,” (a message type  301  which means an error) to the sender  303  of the message packet  300 . 
     If it is determined that a conversation is valid, a message packet  300  is sent from the conversation thread  207  to a node which is designated as a receiver  305  through the protocol manager  230 . The protocol manager  230  converts the protocol to one which conforms to the type of the network to be connected. Therefore, the agent communication system  200  can send and receive a message packet  300  without being aware of the network protocol. 
     Now with reference to FIG.  8  and FIG. 9, the operational condition of each component, at the node which received the message packet  300  so sent, is discussed. 
     The agent communication language manager  203  which has received a message packet  300  from the protocol manager  230  determines that the received message packet  300  is one for receiving the message as it is passed by the “handleMessage,” method. The agent communication language manager  203  instructs the conversation thread control part  205  to process, or handle, the message. In the preferred embodiment of this invention, the protocol manager  230  knows of the existence of the agent communication language manager  203  as the latter internally instantiates, it can send the incoming data to the agent communication language manager  203 . 
     The conversation thread control part  205  determines whether or not to ask the conversation thread  207  to process the message packet  300  with reference to the response ID  307  contained in the message packet  300 . If the conversation thread control part  205  determines that the packet is a new conversation, it generates a new conversation thread  207  and transfers it to the conversation thread  207  for processing. 
     If a conversation thread  207  corresponding to the response ID  307  exists, the conversation thread control part  205  determines that the message packet  300  is not a new conversation and transfers the message packet  300  to the corresponding conversation thread  207  for processing. The message log  211  then memorizes the message packet  300  which is sent to the conversation thread  207  for processing. The conversation content monitoring part loader  215  calls a conversation content monitoring part  217  which conforms to the message type  301  of the message packet  300 . The conversation content monitoring part  217  conducts a policy check as to whether or not a conversation is valid based upon the conversation log stored in the message log  211  and the content  315  of the current message packet  300 . 
     If it is determined that a conversation is valid, the conversation thread  207  transfers control to the interpreter loader  223  for processing. The interpreter loader  223  understands the agent communication language of the message packet  300  and determines whether or not the describing language type  311  contained in the message packet  300  and an interpreter which corresponds to the ontology  313  are stored in an interpreter control table  350  shown in FIG.  10 . 
     If an interpreter which corresponds to the agent communication language, describing language type  311  and the ontology  313  of the received message packet  300  is stored in the interpreter control table  350 , then the content  315  is interpreted by that interpreter. If an interpreter which corresponds to the agent communication language, describing language type  311  and the ontology  313  of the received message packet  300  is not stored in the interpreter control table  350 , then a determination is made as to whether or not an interpreter which corresponds to that combination exists in an interpreter library which is managed (accessible) by the system. It can be appreciated that the interpreter library includes available interpreters that are suitable to operate in accordance with the present invention. 
     If the interpreter exists, it is registered in the interpreter control table  350  and the content  315  is interpreted using that interpreter. If an interpreter which corresponds to a combination of the agent communication language, describing language type  311  and the ontology  313  does not exist in the interpreter library, then a determination is made as to whether or not an interpreter which corresponds to a combination of the describing language type  311  and the ontology  313  exists in the interpreter library. If it does not exist, it is determined that the message packet  300  can not be processed. In the preferred embodiment of this invention, the ontologies are hierarchically structured so that an interpreter of a best matching ontology can be used. 
     It an interpreter and a translator exists that can translate the language of the content to the language that the interpreter can interpret, control is transferred to the translator loader  219  to translate the content  315  into the agent communication language of the discovered interpreter. The translator loader  219  makes a reference to the translator control table  340  and determines whether or not there exists a translator which can execute the requested translation. In the preferred embodiment of this invention, if the translator does not exist, a translator library is searched in a similar way as the interpreter library was searched. If a translator is selected from the translator-library, then an entry is made to the translator control table  340  and the translated content  315  is processed by the selected interpreter. If the translator does not exist in the translator library, then it is determined that the message packet  300  can not be processed. As with the interpreter library, it can be appreciated that the translator library includes available translators that are suited to operate in accordance with the present invention. 
     In the preferred embodiment of this invention, the result of the interpretation by the interpreter  225  is transmitted to the agent  231  where it is processed according to the content of instructions which are described in the content  315 . Depending on what is in the content  315 , either the conversation thread  207  is destroyed, a process is started to begin a new conversation, or a new agent is generated. In the preferred embodiment of this invention, the interpreter  225  returns control to the conversation thread  207 . The conversation thread  207  will standby until another message packet  300  is received. 
     In the preferred embodiment of this invention so far described, the interpretation execution parts are registered in the control tables at the time of execution. However, the interpretation execution parts need not be registered at the time of execution. Instead, a check may be made at the time of execution to start the agent communication system  200  as to what interpretation execution parts exist to form and maintain an interpretation execution part control table. 
     While the message packet  300  moves among nodes in the preferred embodiment of this invention, the message packet  300  may be sent in an attachment to a mobile agent. In such case, the mobile agent  233  moves around places and holds conversation with the message packet  300  attached thereto. It is further possible to carry out complex jobs such as having a conversation at another place using the process result. 
     Movement of a mobile agent over the network is effected by executing the steps shown in FIGS. 12-14 wherein operational conditions of each component of one embodiment of this invention (as shown in FIG. 3) are illustrated. 
     As described above, this invention provides a communication system which is capable of giving a suitable response by using an interpretation execution part which conforms to the content (defined with background concept and vocabulary) of the conversations among agents. 
     In one of the aspects of this invention, a message processing system is provided which enables a high speed processing by reducing unnecessary decision logic. 
     In another aspect of this invention, a message processing system is provided in which resources required for execution are decreased. 
     In still another aspect of this invention, a message processing system is provided which realizes high-speed parallel conversation processing. 
     In a further aspect of this invention, the work and the time required for developing and maintaining a program are decreased as much as possible in providing a support to communication among agents. 
     In a further aspect of this invention, a message processing system is provided which is capable of flexibly dealing with conversations among agents. 
     In a still further aspect of this invention, a message process system is provided which gives less load to a communication network. 
     Although described in the context of preferred embodiments, it should be realized that a number of modifications to these teachings may occur to one skilled in the art. By example, and as discussed above, the teachings of this invention are not intended to be limited to any specific network configuration or protocol. 
     While the invention has been particularly shown and described with respect to preferred embodiments thereof, it will. be understood by those skilled in the art that changes in form and details may be made therein without departing from the scope and spirit of the invention.