Abstract:
An ADM device which is capable of performing LCAS functions, configures a first communication network, and is connected to another ADM device which is connected to a second communication network, comprising an SDH interface for connecting to the other ADM device by SDH connection, an H4 byte monitoring means for monitoring the H4 byte of POH in the SDH interface, an LCAS control information acquisition means for acquiring LCAS control information from the H4 byte monitored by the H4 byte monitoring means, and an LCAS control information transmission means for transmitting LCAS control information acquired by the LCAS control information acquisition means to the other ADM devices, thereby providing an ADM device and signal transmission method which comprises a function for efficiently handling sharp variations in traffic, promotes work efficiency of transmission capacity increase/decrease speed within ADM systems, and actualizes the facilitation of management.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to an ADM (Add Drop Multiplexing) system wherein ADM devices are connected by multistage connections with SONET (Synchronous Optical NETwork), SDH (Synchronous Digital Hierarchy) or Ethernet (registered trademark).  
         [0003]     2. Description of the Related Art  
         [0004]     Conventional ADM systems implementing SONET/SDH are relayed in multi-stages when hierarching storage stations or providing long-haul trunks. However, management operations are generated for every trunk segment when increasing or reducing path speed. In recent years, with the diffusion of corporate L2 services (service providing layer 2 connection between points) and ADSL, systems which transmit Ethernet (registered trademark) traffic using ADM systems are being constructed. Furthermore, with the future diffusion of FTTH (Fiber to the Home), the reception of Ethernet (registered trademark) traffic to ADM systems is expected to increase-drastically.  
         [0005]     ADM systems are generally constructed by implementing SONET or SDH. Although SDH is described in order to simplify explanation, the same also applies to SONET.  
         [0006]     Link capacity adjustment scheme (LCAS) function is a function which increases or reduces path speed. ADM systems which increase and reduce the speed of trunk path bands in conjunction with an opposing device using this LCAS function are also disclosed.  
         [0007]      FIG. 1  is a diagram explaining the operating conditions of the LCAS function in conventional ADM systems.  
         [0008]     In  FIG. 1 , Pattern  1  shows opposing Ethernet (registered trademark) signals when enclosed within a single segment; Pattern  2  shows a case wherein trunk a connection is made by Ethernet (registered trademark); and Pattern  3  shows a case wherein a trunk connection is made by SDH.  
         [0009]     Of these three patterns, LCAS function operation within the ADM system is possible only in Pattern  1 . In Pattern  1 , the transmission of LCAS control information is performed within the ADM segment by transmitting/receiving control codes within an H4 byte area in the POH (Path Over Head).  
         [0010]     In addition, in actual systems, many are constructed such that ADM systems are relayed in multi-stages as in Pattern  2  and Pattern  3  to transmit signals.  
         [0011]     Furthermore, technologies which transmit working traffic using working channels and protection channels by the LCAS function if the ring network is normal and circumvents interference generation area in conjunction with the protection function if interference exists are disclosed (for example, refer to Japanese Patent Publication; Japanese Patent Laid-open Publication No. 2002-359627).  
         [0012]     However, in the above Pattern  2 , because POH is terminated within the ring in the Ethernet (registered trademark) interface which is connected by trunk connection, the H4 byte transmitted and received in the ADM segment cannot be relayed in the Ethernet (registered trademark) trunk connection segment (* 1  in  FIG. 1 ), and therefore, the LCAS function cannot be operated end-to-end simultaneously between plural ADM systems.  
         [0013]     Furthermore, in Pattern  3 , although an H4 byte is relayed in an SDH interface used in trunk connection, the LCAS function cannot be operated end-to-end because there is no system for monitoring and controlling the H4 byte.  
         [0014]     The factors which make the LCAS function inoperable in Pattern  2  and Pattern  3  are as follows:  
         [0015]     (1) H4 byte transmitted and received in ADM segments cannot be relayed to the trunk connection segments in the trunk-connected Ethernet (registered trademark) interface, and therefore, the LCAS function cannot be operated simultaneously between plural ADM systems.  
         [0016]     (2) Although an H4 byte is relayed in an SDH interface, the LCAS function cannot be operated because there is no system for monitoring and controlling the H4 byte.  
         [0017]     Therefore, when increasing and reducing the speed of the trunk path bands in Pattern  2  and Pattern  3 , the operator must set paths by manual operation for each device and each segment, thereby exacerbating operation efficiency. This was also the cause of increase in operation costs.  
       SUMMARY OF THE INVENTION  
       [0018]     An object of the present invention, which has been made with the foregoing circumstances in consideration, is to provide an ADM device and a signal transmission method which comprises a function for efficiently handling sharp variations in traffic, promotes work efficiency of transmission capacity increase/decrease speed within ADM systems, and actualizes the facilitation of management.  
         [0019]     In order to resolve the foregoing issues, the present invention implements a structure such as the following:  
         [0020]     In other words, according to one embodiment of the present invention, the ADM device of the present invention is an ADM device which is capable of performing LCAS functions, configures a first communication network, and is connected to another ADM device which is connected to a second communication network, comprising: a SONET or SDH interface for connecting to the aforementioned other ADM device by SONET or SDH connection; an H4 byte monitoring means for monitoring the H4 byte of POH in this SONET or SDH interface; a LCAS control information acquisition means for acquiring LCAS control information from the H4 byte monitored by the H4 byte monitoring means; and a LCAS control information transmission means for transmitting LCAS control information acquired by the LCAS control information acquisition means to the other ADM devices.  
         [0021]     In addition, according to one embodiment of the present invention, the ADM device of the present invention is an ADM device which is capable of performing LCAS functions, configures a first communication network, and is connected to the aforementioned other ADM device which is connected to a second communication network, comprising: an Ethernet (registered trademark) interface for connecting to the other ADM device by Ethernet (registered trademark) connection; and a LCAS control information transfer means for transferring the LCAS control information to the other ADM device after LCAS control information within the H4 byte transmitted from the other ADM device is terminated in the Ethernet (registered trademark) interface.  
         [0022]     Furthermore, in the ADM device of the present invention, it is preferable that the aforementioned LCAS control information includes starting point device ID for identifying the ADM device which is the starting point and ending point device ID for identifying the ADM device which is the ending point, out of the aforementioned ADM device and the other ADM devices which comprise the first network and the second network.  
         [0023]     Still further, according to one embodiment of the present invention, the signal transmission method of the present invention is a signal transmission method implemented by an ADM device which is capable of performing LCAS functions, configures a first communication network, and is connected to the aforementioned other ADM device which is connected to a second communication network, for monitoring the H4 POH byte, acquiring LCAS control information from this monitored H4 byte, and transmitting the acquired LCAS control information to the aforementioned other ADM devices in a SDH interface for connecting to the other ADM device by SDH connection.  
         [0024]     Still further, according to the present invention, the signal transmission-method of the present invention is a signal transmission method implemented by an ADM device which is capable of performing LCAS functions, configures a first communication network, and is connected to the aforementioned other ADM device which is connected to a second communication network, for transferring the aforementioned LCAS control information to the aforementioned other ADM device after the LCAS control information within the H4 byte transmitted from the other ADM device is terminated in the Ethernet (registered trademark) interface for connecting to the other ADM device by Ethernet (registered trademark) connection. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0025]      FIG. 1  is a diagram explaining the operating conditions of the LCAS function in a conventional ADM system;  
         [0026]      FIG. 2A  is a diagram showing the configuration of an ADM system in a first embodiment of the present invention;  
         [0027]      FIG. 2B  is a diagram showing the configuration of an ADM system in a second embodiment of the present invention;  
         [0028]      FIG. 3  is a diagram showing a signal transmission processing sequence in the first embodiment and the second embodiment of the present invention;  
         [0029]      FIG. 4  is a diagram showing the structure of an H4 byte;  
         [0030]      FIG. 5  is a diagram showing the construction of an ADM device of the present invention;  
         [0031]      FIG. 6  is a diagram explaining the loading of a signal transmission program to a computer in the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0032]     Although application examples for a system implementing SDH are shown within the following explanation, SDH can be replaced with SONET, and the present invention can be applied in the same way.  
         [0033]     One characteristic of the present invention is, in a multi-stage-connected ADM system which is constructed by connecting a first ADM device which configures a first communication network and a second ADM device which configures a second communication network to enable mutual communication, LCAS function is operated end-to-end during relay by SONET, SDH, or Ethernet (registered trademark) which connects these two networks.  
         [0034]     In order to actualize this, the SDH (or SONET) interface of the ADM device which is capable of performing LCAS functions, configures a first communication network, and is connected to the aforementioned other ADM device which is connected to a second communication network, must have a function for monitoring H4 POH byte and acquiring LCAS control information. Through this, LCAS control information can be acquired in the SDH (or SONET) interface and the LCAS function can be performedwhen Ethernet (registered trademark)(as a first communication network) and SDH (as a second communication network) are opposing, or SDH (as a first communication network) and SDH (or SONET) (as a second communication network) are opposing. In this case, by comprising an ON/OFF function for the LCAS function in the SDH (or SONET) interface, it is possible to not operate the LCAS function when opposing conventional SDH (or SONET) interface.  
         [0035]     In addition, by comprising a function for transmitting LCAS control information within the H4 byte, received from the other ADM device during multi-stage connection, to the Ethernet (registered trademark) multi-stage trunk-side after termination in the Ethernet (registered trademark) interface of the ADM device which is capable of performing LCAS functions, configures a first communication network, and is connected to the aforementioned other ADM device which is connected to a second communication network, LCAS function can be operated end-to-end during multi-stage relay by Ethernet (registered trademark).  
         [0036]     Furthermore, by comprising a function for attaching the device IDs of the ADM devices of the starting point and the ending point within the LCAS control information and transmitting, each ADM device configuring the communication network can verify the starting point ADM device and the ending point ADM device during multi-stage connection, and the LCAS function can be operated end-to-end, including the ADM device to be trunked.  
         [0037]     Hereinafter, embodiments according to the present invention are described based on the drawings.  
         [0038]      FIG. 2A  is a diagram showing the configuration of an ADM system in a first embodiment of the present invention.  
         [0039]     In  FIG. 2A , an ADM device  100  comprises: a SDH signal processing part  110  comprising an STM processing part  111  and a VC path processing part  112 ; a cross connecting part  120 ; an Ethernet (registered trademark) signal processing part  130  comprising a trunk path (VCAT: Virtual Concatenation) control part  131  and an Ethernet (registered trademark) signal reception part  132 ; an LCAS processing part  140  comprising a first control information transceiving part  141 , a first control information analysis part  142 , an LCAS control part  143 , a second control information transceiving part  144 , and a second control information analysis part  145 ; and a monitor control part  150 . Additionally, this ADM device  100  configures a communication network through connection with other ADM devices, and configures a multistage connection ADM system through connection with other communication networks by Ethernet (registered trademark) connection.  
         [0040]     The first control information transceiving part  141  is provided with a function for receiving POH comprising H4 byte, which has been sent from the aforementioned other ADM device and transferred from the VC path processing part  112 , and transferring this to the first control information analysis part  142  and a function for transferring POH comprising an H4 byte to the VC path processing part  112  according to instructions from the LCAS control part  143 .  
         [0041]     The first control information analysis part  140  is provided with a function for performing analysis to determine whether the device itself (ADM device  100 ) is the ending point ADM device or is an ADM which performs relay within the aforementioned ADM system, verify the modification speed of VCAT, and determine control content (path condition check (IDLE), path addition (ADD)) based on the LCAS control information within the H4 byte received from the aforementioned first control information transceiving part  141 , and a function for transferring analyzed results to the LCAS control part  143 .  
         [0042]     The LCAS control part  143  is provided with a function for sending instructions to the cross connecting part  120  for controlling the path setting, to the trunk path (VCAT) control part  131  for controlling the path setting for, to the first control information transceiving part  141  for transmitting POH comprising H4 byte, and to the second control information transceiving part  144  for transmitting the LCAS control information, in adherence to the analysis results transferred from the first control information analysis part  140 .  
         [0043]     In addition, the LCAS control part  143  performs analysis of the starting point ADM device and the ending point ADM device and analysis of the changing communication speed according to control from network system management system  300 , and at the same time, instructs the second control information transceiving part  144  to transmit LCAS control information based on the analyzed results.  
         [0044]     The second control information transceiving part  144  is provided with a function for receiving LCAS control information received and transferred from the Ethernet (registered trademark)-side and transferring the information to the second control information analysis part  145  and a function for Ethernet (registered trademark) packetizing LCAS control information according to instructions from the LCAS control part  143  and transferring this to the Ethernet (registered trademark) signal transceiving part  132 .  
         [0045]     The second control information analysis part  145  is provided with a function for performing analysis to determine whether the device itself (ADM device  100 ) is the ending point ADM device or is an ADM which performs relay, verify the modification speed of VCAT, and determine control content (path condition check (IDLE), path addition (ADD)) based on the LCAS control information within the H4 byte received from the second control information transceiving part  144 , and a function for transferring analyzed results to the LCAS control part  143 .  
         [0046]      FIG. 2B  is a diagram showing the configuration of an ADM system in a second embodiment of the present invention.  
         [0047]     In  FIG. 2B , the ADM device  200  comprises: an SDH signal processing part  210  comprising an STM processing part  211  and a VC path processing part  212 ; a cross connecting part  220 ; an SDH signal processing part  230  comprising a VC path processing part  231  and an STM processing part  232 ; an LCAS processing part  240  comprising a first control information transceiving part  241 , a first control information analysis part  242 , an LCAS control part  243 , a second control information transceiving part  244 , and a second control information analysis part  245 ; and a monitor control part  150 . Additionally, this ADM device  200  configures a communication network through connection with other ADM devices, and configures a multistage connection ADM system through connection with other communication networks by SDH connection.  
         [0048]     The first control information transceiving part  241  is provided with a function for receiving a POH comprising an H4 byte, which has been sent from the aforementioned other ADM device and transferred from the VC path processing part  212 , and transferring this to the first control information analysis part  242  and a function for transferring a POH comprising an H4 byte to the VC path processing part  212  according to instructions from the LCAS control part  243 .  
         [0049]     The first control information analysis part  240  is provided with a function for performing analysis to determine whether the device itself (ADM device  200 ) is the ending point ADM device or is an ADM which performs relay within the aforementioned ADM system, verify the modification speed of VCAT, and determine control content (path condition check (IDLE), path addition (ADD)) based on the LCAS control information within the H4 byte received from the aforementioned first control information transceiving part  241 , and a function for transferring analyzed results to the LCAS control part  243 .  
         [0050]     The LCAS control part  243  is provided with a function for sending instructions to the cross connecting part  220  for controlling the path-setting, to the first control information transceiving part  241  for transmitting a POH comprising an H4 byte, and to the second control information transceiving part  244  for transmitting a POH comprising an H4 byte, in adherence to the analysis results transferred from the first control information analysis part  240 .  
         [0051]     In addition, the LCAS control part  243  performs analysis of the starting point ADM device and the ending point ADM device and analysis of the changing communication speed according to control from network system management system  300 , and at the same time, instructs the second control information transceiving part  244  to transmit LCAS control information based on the analyzed results.  
         [0052]     The second control information transceiving part  244  is provided with a function for receiving a POH comprising an H4 byte received from the SDH-side and transferred from the VC path processing part  231  and transferring this to the second control information analysis part  245  and a function for transferring POH comprising an H4 byte to the VC path processing part  231  in adherence to instructions from the LCAS control part  243 .  
         [0053]     The second control information analysis part  245  is provided with a function for performing analysis to determine whether the device itself (ADM device  200 ) is the ending point ADM device or is an ADM which performs relay, verify the modification speed of VCAT, and determine control content (path condition check (IDLE), path addition (ADD)) based on the LCAS control information within the H4 byte received from the second control information transceiving part  244 , and a function for transferring analyzed results to the LCAS control part  243 .  
         [0054]     Next, a signal transmission processing in an ADM system constructed by an ADM device  100  or ADM device  200 , configured as described above, and the same ADM device is explained.  
         [0055]      FIG. 3  is a diagram showing a signal transmission processing sequence in the first embodiment and the second embodiment of the present invention.  
         [0056]     The ADM system described herein is constructed by ADM device  100  or ADM device  200  and the same ADM device as nodes  401 ,  402 ,  403 , and  404 . A first communication network formed by nodes  401  and  402  and a second network formed by nodes  403  and  404  are connected by Ethernet (registered trademark) connection or SDH connection, node  401  is the starting point ADM device and node  404  is the ending point ADM device.  
         [0057]     First, through operation of the network management system (NMS)  300  by an operator, the speed change of node  401  is controlled in step S 301 . Information on the starting point and ending point of the path of which the speed will be changed and the communication speed to be changed is placed in this control information. Here, control information are starting point ID for identifying the starting point node  401 =1, ending point ID for identifying the ending point node  404 =4, and speed change: VC4-3V→VC4-7V.  
         [0058]     Then, in step S 302 , node  401  which received control from the network management system (NMS)  300  analyzes the control content in LCAS control part  143  or  243 .  
         [0059]     Subsequently, in step S 303 , node  401  transmits the results of the analysis in step S 302  to node  402 , which forms the first network which node  401  by ADM connection, by inserting path verification information in an H4 byte. Starting point ID=1, ending point ID=4, speed change: VC4-3V→VC4-7V, which are information on the starting point and the ending point of the path of which the speed will be changed and the speed to be changed, are inserted in the path verification information. In addition, in step  304 , the second control information transceiving part  144  of node  402  verifies path conditions (available space, existence of malfunction) to the cross connecting part  120  and trunk path (VCAT) control part  121 .  
         [0060]     Node  402 , which has received an H4 byte from node  401 , extracts path verification information (available space, existence of malfunction) in the first control information analysis part  142  or  242 , analyzes the contents, and transmits the analysis results to LCAS  143  or  243 , in step S 305 . Here, analysis results are verification instruction of path conditions, that it (node  402 ) is a trunk node, and that communication speed is changed from VC4-3V to VC4-7V. Then, in the LCAS control part  143  or  243  of node  402 , path verification information to node  403  is relayed to the second control information transceiving part  144  or  244 , according to the foregoing analysis results. In the LCAS control part  143  of node  402 , according to the analysis results, instructions are given to packetize and transfer the information, and in the LCAS control part  243 , instructions are given to transfer as an H4 byte. Furthermore, in the second control information transceiving part  144  or  244  of node  402 , the transfer of path verification information (available space, existence of malfunction) to node  403  is performed.  
         [0061]     Then, in step S 306 , the second control information transceiving part  144  of node  402  verifies the path conditions (available space, existence of malfunction) to the cross connecting part  120  and the trunk path (VCAT) control part  121 .  
         [0062]     Node  403 , which has received an H4 byte from node  402  extracts path verification information (available space, existence of malfunction) in the second control information analysis part  145  or  245 , analyzes the contents, and transmits the analysis results to LCAS  143  or  243 , in step S 307 . Here, analysis results are verification instruction of path conditions, that it (node  403 ) is a trunk node, and that communication speed is changed from VC4-3V to VC4-7V. Then, in the LCAS control part  143  or  243  of node  403 , path verification information to node  404  is relayed to the first control information transceiving part  141  or  241 , according to the foregoing analysis results. In the LCAS control part  243 , instructions are given to transfer as an H4 byte. Furthermore, in the first control information transceiving part  141  or  241  of node  403 , the transfer of path verification information (available space, existence of malfunction) to node  404  is performed.  
         [0063]     Then in step S 308 , the second control information transceiving part  144  of node  403  verifies the path conditions (available space, existence of malfunction) to the cross connecting part  120  and the trunk path (VCAT) control part  121 .  
         [0064]     Node  404 , which has received an H4 byte from node  403  extracts path verification information (available space, existence of malfunction) in the second control information analysis part  145  or  245 , analyzes the contents, and transmits the analysis results to LCAS  143  or  243 , in step S 309 . Here, analysis results are verification instruction of path conditions, that it (node  404 ) is a trunk node, and that communication speed is changed from VC4-3V to VC4-7V. Then, in the LCAS control part  143  or  243  of node  404 , path verification information to node  403  is relayed to the first control information transceiving part  141  or  241 , according to the foregoing analysis results. In addition, the LCAS control part  143  or  243  of node  404  instructs the first control information transceiving part  141  or  241  to transmit the verified path condition results. In the LCAS control part  243 , instructions are given to transfer as an H4 byte.  
         [0065]     Then in step S 310 , the second control information transceiving part  144  of node  404  verifies the path conditions (available space, existence of malfunction) to the cross connecting part  120  and the trunk path (VCAT) control part  121 .  
         [0066]     Next, in step S 311 , verification results of the path conditions are transferred to node  403  in the first control information transceiving part  141  or  241  of node  403 .  
         [0067]     Node  403 , which has received an H4 byte from node  404 , adds the verification results of its own (node  403 ) path condition to the received verification results and transfers this to node  403 . In the LCAS control part  143  of node  404 , according to the verification results, instructions are given to packetize and transfer the information, and in the LCAS control part  243 , instructions are given to transfer as an H4 byte.  
         [0068]     Node  402 , which has received H4 byte or the packet from node  403  adds the verification results of its own (node  402 ) path condition to the received verification results and transfers this to node  401 .  
         [0069]     Node  401 , which has received an H4 byte from node  402 , extracts path verification information in the first control information transceiving part  141  or  241 , transfers this to the first control information analysis part  142  or  242 . The first control information analysis part  142  or  242  verifies the path conditions of each node (nodes  402 ,  403 , and  404 ) and determines whether these are normal or not, in step S 314 .  
         [0070]     Then, if the determination result from the first control information analysis part  142  or  242  of node  401  is “normal”, in step S 315 , the LCAS control part  143  or  243  of node  401  instructs the first control information transceiving part  141  or  242  to place path setting information in an H4 byte and transmit this to node  402 . Starting point ID=1, ending point ID=4, speed change: VC4-3V→VC4-7V, which are information on the starting point and the ending point of the path of which the speed will be changed and the speed to be changed, are inserted in the path verification information.  
         [0071]     Node  402 , which has received an H4 byte from node  401 , extracts path setting information in the first control information analysis part  142  or  242 , analyzes the contents, and transmits the analysis results to LCAS  143  or  243 , in step S 317 . Here, analysis results disclose setting instruction of path conditions, that it (node  402 ) is a trunk node, and that communication speed is changed from VC4-3V to VC4-7V. Then, in the LCAS control part  143  or  243  of node  402 , path setting information to node  403  is relayed to the second control information transceiving part  144  or  244 , according to the foregoing analysis results. In the LCAS control part  143  of node  402 , according to the analysis results, instructions are given, for example, to packetize and transfer the information, and in the LCAS control part  243 , instructions are given to transfer as H4 byte. Furthermore, in the second control information transceiving part  144  or  244  of node  402 , the transfer of path setting information to node  403  is performed.  
         [0072]     Then, in set S 318 , the LCAS control part  143  or  243  of node  402  changes the communication speed from VC4-3V to VC4-7V.  
         [0073]     Node  403 , which has received H4 byte from node  402 , extracts path setting information in the second control information analysis part  145  or  245 , analyzes the contents, and transmits the analysis results to LCAS  143  or  243 , in step S 319 . Here, analysis results disclose setting instruction of path conditions, that it (node  403 ) is a trunk node, and that communication speed is changed from VC4-3V to VC4-7V. Then, in the LCAS control part  143  or  243  of node  403 , path setting information to node  403  is inserted, and subsequently relayed to the first control information transceiving part  141  or  241 .  
         [0074]     Then, in step S 320 , the LCAS control part  143  or  243  of node  403  changes the communication speed from VC4-3V to VC4-7V.  
         [0075]     Next, in step S 321 , node  404  which has received H4 byte from node  403  extracts path setting information in the first control information analysis part  142  or  242 , analyzes the contents. The analysis results are transmitted to LCAS  143  or  243 . Here, analysis results disclose setting instruction of path conditions, that it (node  404 ) is a trunk node, and that communication speed is changed from VC4-3V to VC4-7V. In addition, instructions are given to instruct path setting to the cross connecting part  120  and the trunk path (VCAT) control part  131  according to the analysis results.  
         [0076]     Then, in step S 322 , the LCAS control part  143  or  243  of node  404  changes the communication speed from VC4-3V to VC4-7V.  
         [0077]     Furthermore, after completing path setting, the LCS control part  143  or  243  of node  404  instructs the transmission of the results to the first control information transceiving part  141  or  241 , and in step S 323 , the first control information transceiving part  141  or  241  inserts the results of path setting completion to an H4 byte and transfers this to node  403 .  
         [0078]     Node  403 , which has received an H4 byte from node  404 , adds the results of its own (node  403 ) path setting completion to the received H4 byte and transfers this to node  402 . The LCAS control part  143  or  243  of node  403 , for example, packetizes this information and transfers, and the LCAS control part  243  it is transferred as an H4 byte.  
         [0079]     Node  402 , which has received an H4 byte or packet from node  403  adds the results of its own (node  402 ) path setting completion to the received H4 byte and transfers this to node  401 , in step S 325 .  
         [0080]     Then, in step S 326 , node  401  which has received an H4 byte from node  402 , extracts path setting completion results in the first control information transceiving part  141  or  241 , transfers this to the first control information analysis part  142  or  242 . The first control information analysis part  142  or  242  verifies the path setting results from each node (nodes  402 ,  403 , and  404 ) and determines whether or not it has been completed normally.  
         [0081]     Lastly, in step S 327 , after the LCAS control part of node  401  notifies the monitor control part  250  of the determination results from the first control information analysis part  142  or  242 , the monitor control part  250  of node  401  notifies the network management system (NMS)  300  of the path change results.  
         [0082]      FIG. 4  is a diagram showing the structure of an H4 byte.  
         [0083]     As shown in  FIG. 4 , the H4 byte explained herein in the first embodiment and the second embodiment has a Reserve bit. Information indicating the device ID for identifying ADM device  100 ,  200  or nodes  401 ,  402 ,  403 , and  404  in the first embodiment and the second embodiment, information for differentiating trunk nodes, and information for differentiating ending point node are transferred using this Reserve bit.  
         [0084]     Although the embodiments of the present invention have been explained above, with reference to the drawings, the ADM device to which the present invention is applied is not limited to the foregoing embodiments if its functions are being performed. It goes without saying that this can be a single device, a system or an integrated device formed by a plurality of devices, or a system wherein processing is performed via networks such as LAN and WAN.  
         [0085]     In addition, as shown in  FIG. 5 , this can be realized in a system comprising; a CPU  501  connected to bus  509 ; ROM or RAM memory  501 ; input device  503 ; output device  504 ; external recording device  505 ; media driver device  506 ; mobile recording medium  510 ; and network connection device  507 . In other words, it goes without saying that this can be achieved by providing a ROM or RAM memory  502  to which a software program code for realizing the system of the foregoing embodiments is recorded, external recording device  505 , and a mobile recording medium  510  to the ADM device, and the computer of this ADM device reading and executing the program code.  
         [0086]     In this case, the program code read from the mobile recording medium  510  or the like per se actualizes the new functions of the present invention, and the mobile recording medium  510  to which the program code is recorded achieves the present invention.  
         [0087]     As mobile recording medium  510  for providing the program code, flexible disks, hard disks, optical disks, magnet-optical disks, CD-ROM, CD-R, DVD-ROM, DVD-RAM, magnetic tape, nonvolatile memory card, and various recording media recorded via a network connection device  507  (in other words, communication circuit) such as E-mail and online communication can be used.  
         [0088]     In addition, as shown in  FIG. 6 , when a computer (information processing device)  600  executes the program code read to memory  601 , not only are the functions of the foregoing embodiments actualized, but based on the instructions of this program code, the OS running on the computer  600  performs a part of or the entire actual processing, and the functions of the foregoing embodiments are actualized through this processing as well.  
         [0089]     Furthermore, after the program (data)  620  provided by the program code read from a mobile recording medium  610  or the program (data) provider is written to memory  602  provided in the function enhancement board inserted into computer  600  or the function enhancement connected to the computer  600 , based on the instructions of this program code, the CPU provided in this function enhancement board or function enhancement unit performs a part of or the entire processing, and the functions of the foregoing embodiments are actualized through this processing as well.  
         [0090]     According to the present invention, even if the construction of the ADM system becomes complex, end-to-end path management can be facilitated.  
         [0091]     In addition, according to the present invention, because increasing and decreasing speed of trunk path bands spanning a plurality of systems can be performed with one operation, operation efficiency can be improved significantly.  
         [0092]     Furthermore, according to the present invention, because the LCAS function is possible even during multistage connection by SONET or SDH, segments which conventionally had been connected in multi-stages by Ethernet (registered trademark) can be SONET or SDH-compliant, thereby reducing delays and enhancing reliability.