Abstract:
A network management apparatus and a network management system are provided which are capable of reducing setting workloads required when an initial setting operation of a network communication apparatus is performed, and a network structure is changed. The network management apparatus acquires information as to respective network communication apparatus which belong to the same network when an operation of the network is commenced, or when a structure of the network is changed. Then, the network management apparatus determines a concrete operating content of said network communication apparatus based upon the acquired information and an operation policy so as to set the determined operating content. Also, the network management apparatus is equipped with a GUI (Graphical User Interface) used to set a role of the network communication apparatus by a manner.

Description:
[0001]     The present application claims priority from Japanese application JP2005-291901 filed on Oct. 5, 2005, the content of which is hereby incorporated by reference into this application.  
       BACKGROUND OF THE INVENTION  
       [0002]     The present invention is related to a network management apparatus connected to an information communication network and for operating/managing the information communication network in an autonomous manner, and also related to a network management system which is arranged by the network management apparatus and the information communication network.  
         [0003]     Packet switching type information communication networks (hereinafter simply referred to as “networks”) known as IP (Internet Protocol) networks and the like utilized in enterprises are arranged by employing various sorts of network communication apparatus such as routers, switches, gateways, and access points. In order that these networks may function in correspondence with intentions of managers and/or users, these managers and/or users are required to set proper operations with respect to all of these network communication apparatuses.  
         [0004]     There are such trends that currently available networks are constructed in large scales and have high functions. Accordingly, there are similar trends that sorts and amounts as to setting items of packet communication apparatuses are increased. As major setting items, the following setting items are conceivable: security setting items which are required to utilize external networks such as the Internet; network service setting items for guarantee bands which are used by application software such as VoIP (Voice over IP); operation management setting items as to charging, access logs, and monitoring.  
         [0005]     As explained above, if the sorts and amounts of these setting items as to these packet communication apparatuses are increased, then the below-mentioned problems may occur in enterprises: 
    1. Increases in management costs (work time of managers) in connection with increases in work amounts of managers.     2. Delays in network service-in time in connection with increases of setting work time.     3. Increases in mis-setting operations in connection with increases in work contents.    
 
         [0009]     The cause of these problems may be conceived by that complex setting works are increased in an explosive manner. For instance, there is such a case that in order to set security items with respect to an entire network, these security items must be set to almost all of packet communication apparatuses provided within a network, and on the other hand, work amounts of these security setting items are increased directly proportional to scales of networks. Furthermore, in another case that other setting contents such as routing and access controls must be updated in conjunction with the above-explained security setting operations, work amounts thereof are increased in connection with increases in sorts and amounts of these setting items.  
         [0010]     In methods of US2003/0069947 and JP-A-2005-050302, setting works are automatically carried out with respect to communication apparatus so as to solve the above-explained problems.  
         [0011]     Although the above-explained methods disclosed in US2003/0069947 and JP-A-2005-050302 can reduce work amounts of managers, physical configurations of networks must be determined in advance, and setting contents corresponding to the networks must be previously prepared by these managers. As a result, when the structures of the networks are changed and a failure happens to occur in the networks, the managers must perform setting works.  
         [0012]     As changing factors as to the physical configurations of the networks, structures are expanded in a planning manner and failures happen to occur, which may frequently occur. Every time there occurs such an event as an occurrence of a failure or expansion of structure, managers must monitor the failure of a network, must investigate a topology of this network and then, must newly form a configuration definition so as to perform setting works. As a result, work amounts of the above-explained methods are still large.  
       SUMMARY OF THE INVENTION  
       [0013]     To solve the above-explained problems, a network management apparatus, according to one aspect of the present invention, acquires topologies, appliance types and appliance identifiers of respective network communication apparatuses in a network when the network is initially set and a physical configuration of this network is changed, and then, automatically determines roles of these respective network communication apparatuses based upon role assigning information applied by a manger. Furthermore, the network management apparatus acquires such operating contents of the network communication apparatuses to set the acquired operating contents, while these operating contents can satisfy an operation policy given by the manager.  
         [0014]     Also, the network management apparatus, according to another aspect of the present invention, is equipped with a GUI (Graphical User Interface) by which a role can be applied by the manager to the network communication apparatuses. Then, the network management apparatus acquires an operating content of a network communication apparatus based upon the roles applied to the respective network communication apparatuses by employing the GUI by the manager and the operation policy given by the manager, and then sets the acquired functional description of this network communication apparatus.  
         [0015]     More concretely speaking, the present invention is featured by providing a network management system in a network arranged by one or more network management apparatuses, and one or more network communication apparatuses. That is, in the network management apparatus equipped with a network interface connectable with a network, a storage apparatus for storing thereinto a program and data; and a processor for executing a process operation in accordance with the program, the network management apparatus is comprised of: means for acquiring one or more pieces of information among topologies (connection relationship among respective network communication apparatuses), appliance types, and appliance identifiers as to the respective network communication apparatuses belonging to the same network and for holding the acquired information; means for applying roles to the respective network communication apparatuses; means for holding operation policies in which abstractive operating contents are described with respect to the roles; and means for determining concrete operating contents of the respective network communication apparatuses based upon the information and the operation policies of the respective network communication apparatuses, and for setting the determined concrete operating contents to the network communication apparatuses. In the network communication apparatus equipped with: a network interface connectable to the network; a processor for processing a packet received by the network interface; and a storage apparatus for holding a route table required for the processing operation, the network communication apparatus is comprised of: means responding to an information request issued from the network management apparatus; and means for operating in accordance with a setting condition from the network management apparatus. When the operation of the network is commenced and the structure of the network is changed, the network management apparatus acquires one or more pieces of information among the above-explained topologies, appliance types, and appliance identifiers of the respective network communication apparatuses belonging to the same network; the roles are applied to the respective network communication apparatuses by the means for applying the roles; and the network management apparatus determines concrete operating contents of the respective network communication apparatuses based upon the operation policies from the applied roles, and then, sets the determined concrete operating contents to the network communication apparatuses.  
         [0016]     Further, the present invention is to provide a network management system featured by that the network management apparatus is comprised of: means for holding a role assigning rule which describes both roles to be assigned to a network communication apparatus, and a condition with respect to one or more pieces of information among the above-explained topologies., appliance types, and appliance identifiers of such a network communication apparatus, which should be satisfied in order that this network communication apparatus judges as being the roles in correspondence thereto. As the means for applying the roles, the role assigning rule is employed.  
         [0017]     In addition, the present invention is featured by providing such a network management system that the network management apparatus is further comprised of: means for notifying one or more pieces of information among the above-explained topologies, appliance types, and appliance identifiers of the network communication apparatuses in the network to the manager, and for designating a role which is applied to the respective network communication apparatuses. The network management apparatus notifies to the manager, one or more pieces of the information among the above-explained topologies, appliance types, and appliance identifiers of the network communication apparatuses, which are acquired by the network communication apparatuses, and determines concrete operating contents of the respective network communication apparatuses based upon the operation policy from the role designated by the manager based on the notified content.  
         [0018]     Moreover, the present invention is to provide such a network management system featured by that the operating contents described in the operation policy correspond to packet filtering which describes a permission/non-permission of communication among the roles; and operating contents set to the respective network communication apparatuses correspond to operations of packet filtering functions of the network communication apparatuses.  
         [0019]     In accordance with the present invention, the below-mentioned advantages are obtained: 
    1. Since an apparatus of a packet switching network is automatically set, an increase in management costs, a delay in service-in times, and mis-setting operations can be suppressed.     2. A change in a physical configuration of a network is detected, and thus, a setting operation is carried out without intervening of a manager, or by executing a minimum setting work in accordance with network operation policy established in the beginning.    
 
         [0022]     Other objects, features and advantages of the invention will become apparent from the following description of the embodiments of the invention taken in conjunction with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0023]      FIG. 1  is a structural diagram for showing a network where a packet communication apparatus of the present invention is arranged.  
         [0024]      FIG. 2  is a structural diagram of a management apparatus  500  according to a first embodiment of the present invention.  
         [0025]      FIG. 3  is a structural diagram for representing packet communication apparatus  100 ,  110 ,  120 ,  130  and  140 .  
         [0026]      FIG. 4  is a diagram for representing a topology acquiring process operation of the management apparatus  500  according to the first embodiment of the present invention.  
         [0027]      FIG. 5  is a diagram for indicating topology acquiring condition information  534  of the management apparatus  500  according to the first embodiment of the present invention.  
         [0028]      FIG. 6  is a diagram for indicating request receiving ID information  1055  of a packet communication apparatus.  
         [0029]      FIG. 7  shows information contained in a topology notification message which is transmitted by a terminal  121 .  
         [0030]      FIG. 8  indicates neighbor information of the packet communication apparatus  120 .  
         [0031]      FIG. 9  indicates neighbor information of the packet communication apparatus  100 .  
         [0032]      FIG. 10  shows topology information  535  of the management apparatus  500  according to the first embodiment of the present invention.  
         [0033]      FIG. 11  is a flowchart for indicating a role defining process operation of the management apparatus  500  according to the first embodiment of the present invention.  
         [0034]      FIG. 12  is a diagram for showing role definition information  536  of the management apparatus  500  according to the first embodiment of the present invention.  
         [0035]      FIG. 13  is a diagram for showing role assign information  537  of the management apparatus  500  according to the first embodiment of the present invention.  
         [0036]      FIG. 14  is a flowchart for indicating a filter setting process operation of the management information  500  according to the first embodiment of the present invention.  
         [0037]      FIG. 15  is a diagram for showing filter definition information  538  of the management apparatus  500  according to the first embodiment of the present invention.  
         [0038]      FIG. 16  is a diagram for showing filter definition information  539  of the management apparatus  500  according to the first embodiment of the present invention.  
         [0039]      FIG. 17  is a structural diagram for showing a management apparatus  500  according to a second embodiment of the present invention.  
         [0040]      FIG. 18  is a diagram for illustratively indicating a GUI of the management apparatus  500  according to the second embodiment of the present invention.  
         [0041]      FIG. 19  is a diagram for indicating role list information  542  of the management apparatus  500  according to the second embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS  
       [0000]     1. System Arrangement/Apparatus Structure  
         [0042]      FIG. 1  is a network to which a network management system of the present invention has been applied, which is employed in descriptions of the below-mentioned embodiments.  
         [0043]     The network is arranged by an internal network  1  managed by a manager, and an external network  2  which is connected to the internal network  1 . The internal network  1  is arranged by packet communication apparatuses  100 ,  110 ,  130 , and  140 . While the packet communication apparatus  100  has a role of a core switch of the network  1 , this packet communication apparatus  100  has been connected to other packet communication apparatuses  110 ,  120 , and  130 , but has not yet been connected to the packet apparatus  140  under initial condition. The packet communication apparatuses  120 ,  130 ,  140  correspond to floor switches installed on the respective floors, and have stored thereinto terminals  121  and  122 , terminals  131  and  132 , and also, terminals  141  and  142 , respectively. The packet communication apparatus  110  has a role of a gateway which is connected to the external network  2 . Furthermore, a management apparatus  500  according to a first embodiment of the present invention, which manages the internal network  1 , has been connected to the packet communication apparatus  100 .  
         [0044]     Referring now to  FIG. 2 , the management apparatus  500  of the first embodiment will be described.  
         [0045]     The management apparatus  500  contains a network interface  510 , a processor  520 , and a storage apparatus  530 . The storage apparatus  530  stores thereinto a topology acquiring program  531 , a role defining program  532 , a filter setting program  533 , a topology acquisition status information  534 , topology information  535 , role definition information  536 , role allocation information  537 , filter definition information  538 , and filter setting information  539 . The contents of the above-explained programs and information will be explained later.  
         [0046]     Referring now to  FIG. 3 , the packet communication apparatus  100  will be explained. It should be noted that the packet communication apparatuses  110 ,  120 ,  130 , and  140  have similar structures to the structure of the packet communication apparatus  100 . The packet communication apparatus  100  is arranged by network interfaces  1010  and  1020 , a switch  1030 , a route retrieving module  1040 , and a module control management module  1050 .  
         [0047]     The route retrieving module  1040  is arranged by a processor  1041  and a storage apparatus  1042 . The storage apparatus  1042  stores thereinto a route table  1043  and a route retrieving program  1044 . The processor  1041  acquires transfer destinations of packets received from the network interfaces  1010  and  1020  with reference to the route table  1043  in accordance with the route retrieving program  1044 . In the case that the received packets are data packets, the processor  1041  transfers the data packets from a transfer destination network interface by employing the switch  1030 . In the case that the received packets are control packets, the processor  1041  transfers the control packets to the control managing module  1050 .  
         [0048]     The control managing module  1050  is arranged by a processor  1051  and a storage apparatus  1052 . The storage apparatus  1052  stores thereinto an neighbor information distributing program  1053 , a filter setting program  1054 , request reception ID information  1055 , topology acquisition status information  1056 , neighbor information  1057 , and filter information  1058 . The contents of the above-described information will be explained later.  
         [0000]     2. Acquisition of Topology Information  
         [0049]     Referring now to  FIG. 4 , a topology acquiring process operation of the network by the management apparatus  500  in the network of  FIG. 1  will be explained. This topology acquiring process operation is executed by the processor  520  of the management apparatus  500  in accordance with the topology acquiring program  531 .  
         [0050]     First, the processor  520  refers to the topology acquisition status information  534  shown in  FIG. 5 . The topology acquisition status information  534  is constituted by (request message ID, port and reception status), and holds such an information as to whether or not a notification message is received with respect to a request message which is identified by a request message ID transmitted to a certain port. The processor  520  refers to a column of a request message ID of the topology acquisition condition information  534  so as to acquire a request message ID(=x) which is not utilized, and adds such an information as (x, p, Sent) to the topology acquisition status information  534  (S 101 ). In this information, symbol “p” indicates a port connected to the network managed by the management apparatus  500 .  
         [0051]     Next, topology information request message is transmitted to a neighbor packet communication apparatus (S 102 ). A transmission source address of this request message is a MAC address corresponding to an identifier of a network interface of a port to which the request message is transmit; a transmission destination address is a broadcast address; and a message content corresponds to an identifier and a request memory ID (=x) which indicate that this message is a topology information request message. After the transmission of the topology information request message has been accomplished, the management apparatus  500  is brought into a reception waiting status of a topology information notification message.  
         [0052]     Next, description is made of operations of the packet communication apparatus  100  which has received the topology information request message from the management apparatus  500 . This process operation is performed by the processor  1051  of the packet communication apparatus  100  in accordance with the neighbor information distributing program  1053 .  
         [0053]     Firstly, the processor  1051  refers to the request reception ID information  1055  shown in  FIG. 6  by employing the request message ID (=x) of the received topology information request message (S 103 ). In the request reception ID information  1055 , (request message IDs, reception time instants, reception ports, counter MAC addresses) of all of topology information request messages received after the packet communication apparatus  100  has been initiated have been stored. A counter MAC address is equal to a transmission source MAC address of a topology information request message. When the request message ID of the received topology information request message has not already been contained in this counter MAC address, such an entry as (x, present time instant, reception port) is added to the request reception ID information  1055 , and the topology information request message is transmitted from the respective ports “p” other than the reception port (S 104 ). The transmission source address of this message corresponds to an MAC addresses of a port for transmitting the request message (S 104 ), and the request message ID is “x.” In the network of  FIG. 1 , this message is transmitted to the packet communication apparatuses  110 ,  120 ,  130 , and  150 . Also, such information of (x, p, Sent) is added to the topology acquisition status information  1056  (S 105 ). The format of the topology acquisition status information  1056  is identical to that of the topology acquisition status information  534  shown in  FIG. 5 . After the transmission of this message has been accomplished, the packet communication apparatus  100  is brought into a reception waiting status of the topology information notification message.  
         [0054]     Next, description is made of operations of the packet communication apparatus  120  which has received the topology information request message from the packet communication apparatus  100 . It should also be noted that although  FIG. 4  indicates process operations as to only the packet communication apparatus  120 , similar process operations are carried out in other packet communication apparatuses  110 ,  130 , and  140 . This process operation is executed by the processor  1051  of the packet communication apparatus  120  in accordance with the neighbor information distributing program  1053 .  
         [0055]     First, the processor  1051  refers to the request reception ID information  1055  by employing the request message ID (=x) of the received topology information request message (S 106 ). When the request message ID of the received topology information request message has not been already contained in this request reception ID information  1055 , such an entry (x, present time, and reception port) is added to the request reception ID information  1055 , and a topology information message is transmitted from each of the ports “p” except for the received port (S 107 ). A transmission source address of this message is a MAC address of a network interface to which this message is sent, and the request message ID is “x.” Also, such an information (x, p, Sent) is added to the topology acquisition condition information  1056  (S 108 ). After the transmission of this message has been accomplished, the packet communication apparatus  100  is brought into a reception waiting status of the topology information notification message.  
         [0056]     When the terminal  121  (similar to terminals  122 ,  131 ,  132 ,  141 , and  142 ) receives the topology information request message, the terminal  121  transmits the topology information notification message (S 109 ). While the topology information notification message employs the transmission source MAC address of the topology information request message as the transmission source address, this topology information notification message contains as message contents, an identifier indicative of the topology information notification message; a request message ID of the topology information request message; an identifier (“Port 0 ” in this case) of such a port that the terminal  121  receives the topology information request message; and further, information shown in  FIG. 7  (row number (#), an apparatus name (Name), an apparatus type (Type), neighbor node, filter setting , setting ID address). As the apparatus sort, the own apparatus type information (=Endnode) is set, and since the neighbor node is not present at any node except for the node which receives the topology information request message, the neighbor node is an empty column. Since the filter setting operation cannot be carried out in the column for filter setting operation, this column is an empty column. A sub-net address belonging to the own network is set to the column of the setting IP address.  
         [0057]     When the packet communication apparatus  120  receives the topology information notification message from the terminal  121  and the terminal  122 , the packet communication apparatus  120  refers to the topology acquisition status information  1056  from the request message ID and the reception port number of this message so as to acquire a reception status. In the case that the relevant record is not present, or the reception status is “Received”, the packet communication apparatus  120  discards the relevant message. When the reception status corresponds to “Sent”, the packet communication apparatus  120  changes is reception status into “Received” and forms neighbor information  1057  shown in  FIG. 8  (S 110 ).  
         [0058]     The neighbor information  1057  is constituted by (node number (#), apparatus name (Name), apparatus type (Type), neighbor node, filter setting, and setting IP address). The own apparatus information has been already recorded in the node number “0.” In this case, such information as to whether or not which filter setting operation is available for the own apparatus is set to the filter setting column, and an IP address connected in order that an external node performs the own filter setting operation is set to the setting IP address. In an example shown in  FIG. 8 , filter setting operations can be carried out on both an input side (Inbound) and an output side (Outbound), and this example indicates that an IP address for a setting purpose is “192.168.120.1.” 
         [0059]     Also, when the above-explained topology information notification message is received, the packet communication apparatus  120  conducts a neighbor relationship from an identifier of a port and contained in the received topology information notification message and also from the information of  FIG. 7 , and then, stores the conducted neighbor relationship into the neighbor information  1057 . Concretely speaking, in the case that the packet communication apparatus  120  receives a topology information notification message from each of the terminals  121  and  122  connected to “Port  2 ” and “port  3 ”, the packet communication apparatus  120  updates the entire portions of the node members  1  and  2 , and the neighbor node column of the node number 0 of  FIG. 8 .  
         [0060]     Thereafter, the packet communication apparatus  120  checks as to whether or not reception statuses as to all of the records having the relevant request IDs(=x) among the topology acquisition status information  1056  are “Received” (S 111 ). In the case that the reception statuses are “Received”, the packet communication apparatus  120  contains the neighbor information  1057  in the topology information notification message to transmit the resultant neighbor information  1057  (S 112 ). The transmission destination address of the topology information notification message sets the counter MAC address of the record for extracting the request reception ID information  1055  of  FIG. 6  by the request message ID (=x), and the request message ID sets “x.” 
         [0061]     When the packet communication apparatus  100  receives the topology information notification messages from the packet communication apparatuses  110 ,  120 , and  130 , the packet communication apparatus  100  refers to the topology acquisition status information  1056  from the request message IDs and the reception port numbers of the messages so as to acquire a reception status. In the case that the relevant record is not present, or the reception status is “Received,” the packet communication apparatus  100  discards the relevant message. When the reception status corresponds to “Sent”, the packet communication apparatus  100  changes this reception status into “Received” and similarly forms neighbor information  1057  (S 113 ). In the case that the packet communication apparatus  100  receives the topology information notification messages from the packet communication apparatus  110 ,  120 , and  130 , such neighbor information  1057  shown in  FIG. 9  is obtained.  
         [0062]     Furthermore, the packet communication apparatus  100  checks as to whether or not reception statuses as to all of the records having the relevant request IDs among the topology acquisition status information  1056  are “Received” (S 114 ). In the case that the reception statuses are “Received”, the packet communication apparatus  100  contains the neighbor information  1057  shown in  FIG. 9  in the topology information notification message to transmit the resultant neighbor information  1057  (S 115 ). The transmission destination address of the topology information notification message and the request message ID are determined in a similar manner to those of the packet communication apparatus  120 .  
         [0063]     When the management apparatus  500  receives the topology information notification message from the packet communication apparatus  100 , the management apparatus  500  refers to the topology acquisition status information  534  from the request message ID and the reception port number of this received message so as to acquire a reception status. In the case that the relevant record is not present, or the reception status is “Received”, the management apparatus  500  discards the relevant message. When the reception status corresponds to “Sent”, the management apparatus  500  changes this reception status into “Received” and forms such topology information  535  shown in  FIG. 10  in a similar manner to the topology information  535  shown in  FIG. 10  (S 116 ).  
         [0064]     As previously explained, since the management apparatus  500  executes a topology acquisition process operation, the management apparatus  500  can acquires the topology of the network. This topology acquisition process operation is carried out in a periodic manner, or when a change of a network is detected.  
         [0000]     3. Role Definition  
         [0065]     Referring now to a flowchart of  FIG. 11 , a description is made of a role definition process operation of a packet communication apparatus by the management apparatus  500 . This process operation is carried out by the processor  520  of the management apparatus  500  in accordance with the role defining program  532 .  
         [0066]     The manager has previously applied such a role definition information  536  indicated in  FIG. 12  to the management apparatus  500 . While the role definition information  536  is arranged by (role and condition), one or more pieces of conditions can be set with respect to one role. As the condition, the following conditions can be designated: That is, it is possible to designate that whether or not either a name (Name) or a type (Type) is made coincident with respect to a certain node, or whether or not a designated node is contained in a neighbor node (Neighbor) of a certain node.  
         [0067]     When the processor  520  commences a role definition (S 201 ), the processor  520  firstly starts a loop as to each node “N” contained in the topology information  535  (S 202 ). Furthermore, the processor  520  commences a loop as to each of roles “R” of the role definition information  536  shown in  FIG. 12  (S 203 ), and furthermore, starts a loop related to the respective conditions “C” of the role “R” (S 204 ).  
         [0068]     Next, the processor  520  judges as to whether or not the node N can satisfy the condition C (S 205 ). When such a condition is found out that the node N cannot satisfy the condition C, the processor  520  performs a similar judging operation as to the next role (S 206 ). In the case that the node N can satisfy all of conditions, the processor  520  assigns a role “R” to the node N (S 207 ), and then, stores this content to the role assign information. In such a case that a role which can satisfy all of these conditions cannot be found out, the processor  520  assigns “no role” to the node N (S 208 ), and then, stores the content thereof in the role assign information  537 . The processor  520  executes the above-explained operations with respect to all of nodes (S 209 ).  
         [0069]     Since the role definition process operation is carried out by the processor  520  in accordance with the above-described manner, the role assign information  537  can be formed. Concretely speaking, the role assign information  537  can be obtained from the topology information  535  of  FIG. 10  and the role definition information shown in  FIG. 12 .  
         [0070]     This role definition process operation is carried out when the role assign information  537  is required to be updated, for example, the topology information  535  and the role definition information  536  are changed.  
         [0000]     4. Filter Setting and Distributing Operations  
         [0071]     Next, a filter setting process operation by the management apparatus  500  will now be explained with reference to a flowchart of  FIG. 14 . This process operation is carried out by the processor  520  of the management apparatus  500  in accordance with a filter setting program  533 .  
         [0072]     In the filter setting operation, filter definition information  538  shown in  FIG. 15  is employed which is set by the manager. The filter definition information  538  is constructed of (From, To, Flow, Action). This filter definition information  538  defines a processing method (Action) related to a packet which is indicated by a condition of “Flow” flowing from “Flow” to “To”. If “Action” of a packet is “Accept”, then the processing method passes this packet through a network, whereas if “Action” of a packet is “Drop”, then the processing method discards this packet on the network. With respect to a packet which is coincident with conditions of a plurality of entries, a processing method of an entry described at the uppermost grade is applied. An entry in which all of “From”, “To”, “Flow” are indicated by symbol “*” represents a process operation (default process operation) with respect to a packet which is not applicable to other entries.  
         [0073]     When the processor  502  commences a filter setting operation (S 301 ), the processor  502  clears the filter setting information  539 . In a general-purpose packet transfer apparatus, all of flows are transferred without being filtered under this condition that a filter is not set.  
         [0074]     Next, a loop of each entry of the filter definition information  538  is commenced (S 303 ). As to the respective entries (From, To, Flow, Action), all of paths are acquired (S 304 ) through which packets probably pass when the packets are directed from a node group indicated by “From” to a node group indicated by “To.” Then, a loop as to each the acquired paths “P” is commenced (S 305 ). In the loop as to each of the paths P, first of all, filter points (N, Q, D) are acquired (S 306 ) which corresponds to such a place that a filter setting operation can be carried out on the path P by employing the topology information  535 . In this case, symbol “N” shows a node, symbol “Q” indicates a port, and symbol “D” represents a direction indicative of one of inbound/outbound. For instance, in the topology information  535  shown in  FIG. 10 , filter points of paths through which packets directed from a node group “floor end” (namely, node  4  to node  7  in  FIG. 13 ) to a node group “undefined” (namely, nodes  8  and  9  in  FIG. 13 ) probably pass correspond to (node  2 , port  2 , inbound), (node  2 , port  1 , outbound), (node  1 , port  2 , inbound), (node  1 , port  3 , inbound), and (node  1 , port  3 , outbound). Although the node  3  is also involved in the paths, the filter setting operation cannot be carried out in this node  3  in accordance with the topology information  535  of FIG.  10 . As a result, the node  3  does not constitute the filter point.  
         [0075]     Next, the processor  520  checks as to whether or not one or more pieces of the above-acquired filter points are present. When one or more pieces of the acquired filter points are present, the processor  520  adds (N, Q, D, Flow, Action) to the filter setting information  539  with respect to all of the filter points (S 307 ). To the contrary, when one or more pieces of the acquired filter points are not present, the processor  520  further checks as to whether or not “Action” is “Drop” (S 309 ). If “Action” is “Drop”, then there are some possibilities that the network may cause a not-intended packet to flow. As a result, the processor  520  issues such a warning to the manager (S 310 ).  
         [0076]     When the above-described process step is ended, the filter setting operation is advanced to a next path (S 311 ). When all of the paths are processed, the filter setting operation is advanced to next filter definition information (S 312 ).  
         [0077]     When the above-described filter setting process operation is accomplished, the filter setting information  539  is actually set to the respective nodes. Concretely speaking, such filter setting information  539  shown in  FIG. 16  is formed from the topology information  535  shown in  FIG. 10 , the role assigning information  537  indicated in  FIG. 13 , and the filter definition information  538  shown in  FIG. 15 .  
         [0078]     With employment of the above-explained arrangement, in the network management system containing the management apparatus  500  according to the first embodiment of the present invention, the automatic setting operation of the filter can be realized.  
         [0000]     5. Supplement of Filter Setting Operation  
         [0079]     In a filter setting operation, a transmission source IP address of a packet which is transmitted in a terminal, it is easy to employ a transmission source IP address except for such a transmission source IP address supposed by the manager. Accordingly, there is a better case that the transmission source IP address of the terminal, which is supposed by the manager, is excluded from a condition of a filter, and a packet with respect to an arbitrary transmission source IP address is filtered. In the present invention, if the manager performs such a designation as to a management terminal, then a filter setting operation can be implemented without employing a transmission source IP address of a packet of a filter setting operation where “Action” is “Drop” as a condition.  
         [0000]     6. Automatic Setting Operation Executed when Packet Communication Apparatus is Added  
         [0080]     Next, description is made of automatic setting operations when an unconnected packet communication apparatus  140  is connected to the packet communication apparatus  100  after the above-described automatic setting operation has been carried out.  
         [0081]     When the management apparatus  500  detects a connection of the packet communication apparatus  140 , the management apparatus  500  again performs the above-explained topology acquiring process operation, role defining process operation, and filter setting process operation. The role of the packet communication apparatus  140  is automatically assigned by the role defining process operation, so that filter setting information which should be set to the packet communication apparatus  140  may be acquired by the filter setting process operation.  
         [0082]     In this case, as a method of detecting the packet communication apparatus  140 , the following methods may be conceived: a method in which the packet communication apparatus  100  monitors a port to which an appliance is not connected; a method in which when the packet communication apparatus  140  is connected, the packet communication apparatus  140  transmits a control packet to the packet communication apparatus  100 ; a method in which the manager clearly notifies the detection to the management apparatus  500 , and so on.  
         [0083]     With employment of the above-described operations, when the packet communication apparatus  140  is conducted, the filter setting operation can be automatically carried out with respect to the packet communication apparatus  140  while the manager does not perform the setting operation.  
         [0000]     7. Role Definition by GUI  
         [0084]     Next, description is made of a second embodiment in which the role defining process operation is carried out by GUI (Graphical User Interface). Since only a role defining process operation of the second embodiment is different from that of the first embodiment, only this different process operation is explained.  
         [0085]      FIG. 17  indicates a management apparatus  500  according to a second embodiment of the present invention.  
         [0086]     The management apparatus  500  contains a network interface  510 , a processor  520 , and a storage apparatus  530 . The storage apparatus  530  stores thereinto a topology acquiring program  531 , a GUI role defining program  541 , a filter setting program  533 , topology acquisition status information  534 , topology information  535 , role list information  542 , role assigning information  537 , filter defining information  538 , and filter setting information  539 .  
         [0087]     With reference to  FIG. 18 , a role defining process operation using the GUI by the manager will now be explained. This process operation is carried out by the processor  520  of the management apparatus  500  in accordance with the GUI role defining program  541 .  
         [0088]     The control apparatus  500  is equipped with a display apparatus  550  and input apparatus  502  and  503 , which are shown in  FIG. 17 . The display apparatus  550  contains a topology information display module  551 , and a role display module  552 . In the management apparatus  500 , contents of both the topology information  535  and the role assigning information  537  are displayed on the topology information display module  551 , and information of role list information  542  is displayed on the role display module  552 . The role list information  542  corresponds to such a list that roles represented in  FIG. 18  are described.  
         [0089]     When the manager selects either a packet communication apparatus or a terminal, to which a role is set among the topology information displayed on the topology information display module  551  and designates a role from the role display module  552  by employing the input apparatus  502  and  503 , the management apparatus  500  writes a content of this designation into the role assigning information  537 .  
         [0090]     When the role assigning information  537  is updated by the manager, the processor  520  starts the above-explained filter setting process operation.  
         [0091]     In accordance with the above-explained method, the automatic setting operation of the network communication apparatus by way of the setting operation by the manager with employment of the GUI can be carried out.  
         [0000]     8. Supplement of Role Definition by GUI  
         [0092]     Although the GUI is employed in the above-described second embodiment, the role may be alternatively set by employing another type of user interface such as CUI (Character User Interface).  
         [0093]     Another method may be alternatively carried out. That is, as to a packet communication apparatus and a terminal to which roles are not defined by the GUI in the second embodiment, the role may be defined by executing the role definition process operation using the role definition information  537  explained in the first embodiment.  
         [0094]     It should be further understood by those skilled in the art that although the foregoing description has been made on embodiments of the invention, the invention is not limited thereto and various changes and modifications may be made without departing from the spirit of the invention and the scope of the appended claims.