JP2008198041A - Device monitoring network system and trap management method of snmp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device monitoring network system and a trap management method of SNMP (simple network management protocol), capable of reducing processing load and network traffics by efficiently performing omission check of TRAP and retransmission processing of TRAP for TRAP which occurs in large quantities. <P>SOLUTION: The trap number is counted for every unit time in a TRAP generation part A of a network element NE (monitoring object device), and when the trap number exceeds a threshold, traps are sorted to trap groups sorted by monitoring function item. Each trap is transmitted from a TRAP transmission part C to a NMS (network management system) while assigning a trap group number assigned to each trap group and a trap sequence number. In the NMS, continuity check of receipt is performed for each trap group, and omission check and retransmission request of traps are performed by trap group units. TRAP for which retransmission is requested is reedited for each trap group and transmitted as one trap to the NMS. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a device monitoring network system using SNMP (Simple Network Management Protocol) and a trap management method for SNMP, and in particular, efficiently processes a large number of trap commands that occur when the status of a monitored device frequently changes. In addition, the present invention relates to a device monitoring network system and an SNMP trap management method capable of reliably and easily retransmitting a trap lost due to a network failure or the like without putting a burden on the network.

  A device monitoring network system using an SNMP network includes a network management device (Network Management System: hereinafter referred to as NMS) having an SNMP manager function and a monitoring target device (Network Element: hereinafter referred to as NE) having an SNMP agent function. Then, the NE notifies the NMS of the status change and event occurrence information such as the occurrence of a failure detected or its recovery, and the occurrence of the event using an SNMP trap command (asynchronous interrupt notification: hereinafter referred to as TRAP).

  However, SNMP commands such as TRAP are transmitted and received using UDP (User Datagram Protocol), which is a connectionless protocol with a light load, and UDP has no guarantee of reliability. Therefore, in order to ensure the reliability of TRAP transmission, a continuous sequence number is assigned to the TRAP issued from the NE and transmitted to the NMS. The NMS detects a drop in the received TRAP based on the TRAP sequence number. A technique for instructing retransmission of the TRAP is proposed by the following Patent Document 1 (“trap missing detection method and detection method in IP network”) and the like.

Further, regarding a technique in which the TRAP transmitted to the NMS is once logged in the NE, the TRAP data is extracted from the logged area at the time of a retransmission request from the NMS, and retransmitted to the NMS, the following Patent Document 2 (“ Network management system that detects and compensates for loss traps ”).
JP 2003-244142 A Japanese Patent Laid-Open No. 2004-221849

  In a network management system using SNMP, when a state change occurs in the NE, one TRAP is transmitted for each state change to the NMS. When the NMS receives the TRAP, the NE transmits the TRAP to the NE that has transmitted the TRAP. The information transmission request is issued by the get request command (hereinafter referred to as “Get request”), and the details of the state change are received by receiving the get response command (hereinafter referred to as “Get response”) from the NE in response to the Get request. Recognize information.

  In addition, when a large number of state changes occur in the NE and a large amount of TRAP is transmitted from the NE to the NMS, depending on the network conditions, a plurality of discontinuous TRAP delivery failures may occur, and TRAP omissions may occur. The burden of the check processing increases, and a number of commands must be exchanged between the NE and the NMS for a series of retransmission processing for the detected dropped TRAP, which causes a lot of load on the NMS. As a result, TRAP disappears and network traffic increases.

  In addition, when a large amount of state change notification TRAP packets are issued from the NE, the TRAP packets of specific monitoring items from the same function group or the same unit occupy the majority, and state changes of other monitoring items that occur occasionally In the NMS detection, a delay occurs due to the processing time lag due to the transmission of a large number of packets, and proper processing is not performed for the state change due to packet discarding or the like. In the worst case, the monitoring target device must be reset. Sometimes it would disappear.

  The present invention solves the above problem, and when a large amount of TRAP for state change or event notification occurs in the NE, a large amount of TRAP issued from the NE can be efficiently processed by the NMS, and a plurality of TRAPs can be dropped. Even if it occurs discontinuously, the TRAP retransmission process can be completed with a small number of packet exchanges, thereby reducing the TRAP processing load in the NMS and reducing the network traffic. A network system and SNMP trap management method are provided.

  In order to solve the above-described problem, the present invention counts the number of traps generated in the monitoring target device per unit time, compares the number of traps per unit time with a preset threshold value, and determines the number of traps. When the threshold is exceeded, the generated traps are sorted by monitoring function item, and the trap group is grouped for each monitoring function item, and the trap group number assigned to the trap group is added in addition to the trap sequence number. The network management device checks the continuity of the trap for each trap group with respect to the received trap and the first configuration for holding the transmitted trap group in the monitored device and the network management device. The trap sequence number and the trap group number that can identify the trap that has been dropped when the trap has been dropped A second configuration for transmitting a given set request command to the monitoring target device, and a trap of a transmitted trap that is internally held by the monitoring target device by analyzing the set request command from the network management device The group number and the TRP sequence number are compared with the trap group number and the trap sequence number given to the set request command, the dropped traps that have not been received by the network management device are determined, and all of the dropped traps are set to 1. The first feature is that a third configuration is provided for re-editing one trap, assigning a new trap sequence number, transmitting the trap to the network management apparatus, and clearing the held transmitted trap. .

  In the second configuration, the reception status of the trap group is monitored by the continuous trap group reception timer, and when the continuous trap group reception timer times out without receiving the final trap of the trap group, A configuration in which a get request command requesting retransmission of all traps is transmitted to the monitoring target device; in the third configuration, the get request command from the network management device is analyzed, and a trap group number requested to be retransmitted A second feature is that a means for re-editing all of the traps into one trap, assigning a new trap sequence number, and transmitting to the network management apparatus is provided.

  In the second configuration, a set request transmission timer that is started each time a set request command is transmitted to the monitoring target device and is stopped when the first trap is received after the set request command is transmitted is provided. A configuration in which when a transmission timer times out, a set request to which the latest trap sequence number and the latest trap group number held in the network management device are assigned is transmitted to the monitoring target device, and the set request transmission timer is restarted. The third feature is that it is provided.

  In the third configuration, when a trap is re-edited by a set request command from the network management apparatus, a new trap sequence number different from the retransmission trap is assigned to a newly generated trap during the retransmission trap editing. When the trap is re-edited by the get request command from the network management device, the trap newly belonging to the same monitoring item generated at the time of the trap re-editing is taken into the re-editing trap being edited. A fourth feature is that a configuration for re-editing and transmitting to the network management apparatus is provided.

  According to the present invention, a large amount of TRAP that occurs when a state change frequently occurs in a monitoring target device is classified by monitoring item, and each is made into a TRAP group, and TRAP continuity check and retransmission control are performed in units of TRAP groups. By doing so, the processing load in the network management apparatus is reduced and the efficiency of the processing can be improved.

  In addition, it is possible to reduce the burden of the TRAP dropout check process by determining whether the TRAP group as a whole is valid or invalid by determining whether or not the final trap of the TRAP group is delivered, and treating the entire TRAP group as invalid. It is possible to transmit a retransmission request as a single command collectively as a TRAP group without transmitting a Set request for a retransmission request in small increments, and to suppress an increase in network traffic.

  In addition, even when there is no TRAP to be notified from the NE to the NMS, the NE confirms the normality of the TRAP reception in the NMS by periodically sending a Set request with the TRAP information in the NMS to the NE. And the difference in the TRAP transmission / reception state between the NE and the NMS can be recognized.

  Further, in the NE, when a Set request or Get request for requesting a TRAP retransmission from the NMS is received, a TRAP that needs to be retransmitted can be generated in units of TRAP groups. Such events can be re-edited together, for example, when repeated occurrences, and TRAP re-editing can be performed efficiently.

  Further, since the re-edited TRAP is notified to the NMS as one new TRAP, the NMS does not need to recheck the TRAP sequence number requested for retransmission without burdening the network. Is reduced, and efficient processing can be performed.

  FIG. 1 shows a configuration example of the NE of the present invention, and FIG. 2 shows a configuration example of the NMS of the present invention. The present invention comprises NE (1) and NMS (2), and NE (1) and NMS (2) are connected via an IP network (3). NE (1) constantly monitors the status of each monitoring item in NE (1) by the status change / event aggregation unit, collects status information, and when a status change is detected, generates TRAP for the status change information. The part (A) is notified, and a new TRAP is generated by the TRAP generation part (A).

  The processing of the TRAP generator (A) will be described with reference to FIGS. When receiving the information on the state change, the TRAP generating unit (A) executes a process of generating a new TRAP (3-1), and when generating the new TRAP, counts the generated TRAP using a TRAP counter (3). -2).

  This count value T_cnt is reset at the timing of receiving the “unit time timeout notification” (e) from the unit time notification timer handler (G), and repeats counting from zero each time. The TRAP generator (A) holds the maximum number of TRAPs that can be processed as the normal operation of NE (1) as the threshold value TH, and always monitors whether the count value T_cnt exceeds the threshold value TH (3-3). .

  If the count value T_cnt (that is, the number of generated TRAPs) is within the threshold TH, the generated TRAP is notified to the TRAP transmitting unit (C) as a “TRAP transmission request” (a) (3-4). If the threshold value TH is exceeded, it is determined that TRAP generation occurs frequently due to frequent state changes, and in order to improve processing efficiency, the TRAP is sent to the TRAP analysis unit (B) “TRAP analysis request” (b) (3-5).

  The unit time and the TRAP counter will be described with reference to FIG. As an example, the threshold TH for the number of TRAP counters is set to 30. In FIG. 4, TRAP counter = 5 in unit time (1) and is within the threshold range, so TRAP is a single process. In the next unit time (2), the TRAP counter exceeds 30 and finally becomes 35. In this case, even if the TRAP counter exceeds the threshold value 30 even during the unit time (2), the TRAP counter is generated. Is subject to analysis.

  In the unit time (3), the TRAP analysis target state from the unit time (2) continues, and the TRAP counter at the time of the unit time (3) time-out is 41, which exceeds the threshold value. The TRAP generated in step 2) is also subject to TRAP analysis. In the unit time (4), the TRAP analysis target state is continuing, and during this period, the TRAP counter is within the threshold range, but remains in the TRAP analysis target state until the unit time (4) times out. Since the TRAP counter is within the threshold range at the time of unit time (4) timeout, the generated TRAP is in a single processing state from the next unit time (5).

  Next, the TRAP analysis unit (B) called from the TRAP generation unit (A) will be described with reference to FIG. 1, FIG. 5, and FIG. The TRAP for which the TRAP analysis request (b) has been made by the TRAP generation unit (A) is the TRAP analysis unit (B), and the monitoring item list shown in FIG. Search based on (5-1). A monitoring item is discriminated by the search, and TRAP is stored in a predetermined area for each monitoring item in the TRAP distribution holding table (5-2).

  At this time, the TRAP group number and the TRAP sequence number are not given. Next, when a TRAP of the same monitoring item is notified, it is stored in a location next to the previously stored TRAP storage location. Each time a TRAP is stored, a serial number in the group (TRAP group detailed number) is assigned to the TRAP.

  Then, at the timing of receiving the “unit time timeout notification” (e) from the unit time notification timer handler (G), the distribution process for each monitoring item is temporarily closed, and a plurality of TRAPs are registered for each monitoring item. In this case, a TRAP group number and a continuous flag for each monitoring item are assigned to each TRAP (5-3). This TRAP group number is not unique for each monitoring item, and is given the latest number at that time.

  After assigning various numbers, each TRAP group is notified to the TRAP transmission unit (C) as a “TRAP transmission request” (c) (5-4). When only one TRAP is registered for each monitoring item, the TRAP group number is not assigned, and the TRAP transmission unit (C) is notified as a single TRAP. After notifying each TRAP to the TRAP transmission unit (C), all TRAP distribution holding tables are cleared (5-5).

  As the monitoring items, as shown in the list of FIG. 6, for example, system failure → monitoring item 1, interface ALM is monitoring item 2, in-route monitoring impossible → monitoring item 3, AIS reception → monitoring item 4, AIS transmission → monitoring Item 5, Light output alarm → Monitoring item 6, Wireless line switching impossible → Monitoring item 7, Forced switching → Monitoring item 8, SV board failure → Monitoring item 9, 150M-IF board failure → Monitoring item 10, 50M-IF board Failure → monitoring item 11... Network abnormality → monitoring item N

FIG. 6 shows a region for each monitoring item in the TRAP distribution holding table of the TRAP analysis unit (B). The monitoring item-specific area shown in FIG.
(* 1) About each monitoring item holding area-Each monitoring item area is fixed for each monitoring item name.
When a “unit time timeout notification” (e) is received from the unit time notification timer handler, a TRAP group number and a group detail number are assigned to each monitoring item area. The sequence number is assigned by the TRAP transmission unit (C).
For each monitoring item area length, a device-specific value is determined by tuning by the user.

(* 2) About the latest continuous TRAP group number-The value of 0x00000001 to 0xFFFFFFFF (4294967295) holds the latest TRAP group number assigned at present as the TRAP group number. This number is used cyclically. However, 0 represents single TRAP, and 0 is not used for the TRAP group number.

(* 3) Continuation flag-0x01 indicating the presence of continuous TRAP is assigned from the first TRAP of the TRAP group to the TRAP immediately before the last TRAP.
Only 0x00 indicating no continued TRAP is given to the last TRAP of the TRAP group.
・ For single TRAP, 0x00 (no continuous TRAP) is given.

(* 4) TRAP group number-The latest continuous TRAP group number described in * 2 above is read, and a value obtained by adding 1 to the read value is assigned to each TRAP as a TRAP group number.
The higher number of the monitoring item is the young TRAP group number, and is assigned to the TRAP of the monitoring item in which two or more TRAPs are stored in one monitoring item.
-For single-shot TRAP with only one TRAP, 0x00 indicating that it is single-shot is assigned.

(* 5) About the TRAP group detailed number-A serial number is assigned to each TRAP in the TRAP group of one monitoring item, starting from 1 on a first-come-first-serve basis. This is used when checking for missing TRAP at the NMS.
・ 1 is also assigned to single TRAP.

(* 6) Sequence number • The sequence number is a serial number assigned to TRAP in the entire system, so it is not assigned by the TRAP analysis unit (B). Assigned immediately before transmission to the NMS (2) by the TRAP transmission unit (C).

  Next, the processing of the TRAP transmission unit (C) will be described with reference to FIGS. First, it is checked whether the TRAP transmission request is a new TRAP transmission request or a retransmission TRAP transmission request (7-1). In the case of a new TRAP transmission request, the TRAP playback state (I) is read (7-2).

  It is checked whether the TRAP playback state (I) is “normal state” or “TRAP playback” (7-3). If the TRAP playback state (I) is “normal state”, the TRAP is notified continuously for each TRAP of the notified TRAP or TRAP group. A TRAP sequence number is assigned (7-4), and TRAP transmission (d) to the NMS is executed (7-5). After the transmission, each TRAP of the currently transmitted TRAP or TRAP group is stored in the transmitted TRAP holding table (H) (7-6).

  When the TRAP playback state is “TRAP playback”, the TRAP requested for transmission is notified to the retransmission TRAP generation unit (F) as a “TRAP loading request” (m) (7-7). The retransmission TRAP generation unit (F) performs a monitoring item check on the TRAP, and if it does not match, it returns it to the TRAP transmission unit (C) as it is as a “retransmission TRAP transmission request” (l). And the TRAP transmission unit (C) transmits the TRAP with the return flag to the NMS as normal TRAP.

  Returning to the determination in step 7-1 described above, when the TRAP transmission request is a retransmission TRAP transmission request, the latest TRAP sequence number is assigned as in the case of the new TRAP (7-8) and transmitted to the NMS (7 -9). However, after that, all TRAP information related to the TRAP stored in the transmitted TRAP holding table (H) is cleared (7-10).

Here, a configuration example of the transmitted TRAP holding table (H) shown in FIG. 8 will be described.
(* 1) About the TRAP storage area • Store in order from the area [0].
-Single-shot TRAP stores only 1 TRAP information in one area.
The TRAP group stores all TRAP information of one TRAP group in one area.
When the TRAP storage area is cleared, the area after the area is moved up and stored.
The device-specific values are determined by tuning by the user for the area length and the number of TRAP storage areas.

(* 2) About the latest TRAP sequence number The latest TRAP sequence number assigned at the present time is stored as a value of 0x00000001 to 0xFFFFFFFF (4294967295). This value is used cyclically.
When the TRAP transmission unit (C) stores TRAP in the transmitted TRAP holding table (H), it stores a value obtained by adding 1 to the latest sequence number of TRAP stored in the area. Further, the sequence number given to TRAP at the time of TRAP transmission (d) is also given this sequence number.

(* 3) Latest continuous TRAP group number-The latest TRAP group number assigned at present is stored as a value of 0x00000001 to 0xFFFFFFFF (4294967295). Used cyclically. However, 0 indicates single TRAP and is not used for the TRAP group number.

  Next, processing on the NMS side that receives the TRAP transmitted from the NE will be described. The TRAP receiver (J), which is a window for receiving TRAP from the NE, will be described with reference to FIG. 2, FIG. 9, and FIG. When the TRAP transmission (d) is received by the TMS receiver (J) of the NMS, the Set request transmission timer (T1 timer) is first stopped (9-1).

  Next, it is checked whether the received TRAP is a single shot or a TRAP of a continuous TRAP group (9-2). In the case of single-shot TRAP, TRAP data is stored in the reception TRAP management table (P) shown in FIG. 10 (9-3), and a “TRAP analysis request” (n) is transmitted to the command analysis unit (K) (9-4). ).

  When the reception TRAP is a TRAP of the continuous TRAP group, the continuous TRAP group reception timer (T2 timer (O)) is first stopped (9-5). The T2 timer monitors the reception state of the continuous TRAP group. Next, the received TRAP data is written in the reception TRAP management table (P) (9-6). Even in the continuous TRAP group, writing is performed every time one TRAP is received.

  Next, it is checked whether the continuous flag of the TRAP is ON or OFF (9-7). If the continuous flag is ON (with continuous TRAP), the T2 timer (O) is started (9-8), and the continuous TRAP is set. Wait for reception. When the continuous flag of the TRAP is OFF (final TRAP in one TRAP group), it is checked whether or not the previous state of the continuous flag is ON (9-9). If the previous state is ON, the command analysis unit ( “TRAP analysis request” (n) is transmitted to K) (9-10). At this time, the timers T1 and T2 are not activated.

Here, a configuration example of the reception TRAP management table (P) illustrated in FIG. 10 will be described.
(* 1) TRAP number storage area • Stored in order from the [0] area.
-Single-shot TRAP stores only one TRAP information in one area.
The continuous TRAP group stores information for all TRAPs in one TRAP group in one area.
When the TRAP storage area is cleared, the area after the area is moved up and stored.
The device-specific values are determined by tuning for the area length and number of TRAP storage areas.

(* 2) Regarding the latest TRAP sequence number-A value of 0x00000001 to 0xFFFFFFFF (4294967295) is cyclically used.
・ The latest sequence number for which reception has been confirmed continuously is stored.

(* 3) Regarding the latest continuous TRAP group number: • 0x00000001 to 0xFFFFFFFF (a value of 4294967295 is used cyclically. However, 0 is used to indicate one-shot TRAP.
Stores the latest TRAP group number for which reception has been confirmed continuously.

(* 4) Continuous flag • 00 indicates that the continuous flag is OFF, that is, the last TRAP of a single or continuous TRAP group.
01 indicates that the continuous flag is ON, that is, reception of continuous TRAP is started or reception is ongoing.

  In the example shown in the figure, since the TRAP continuous flag of sequence number 22 of TRAP group number 02 is OFF (00), TRAP group number 02 indicates that reception has been completed. After reception of all TRAPs with TRAP group number 02 is completed, the TRAP number is checked to recognize that the sequence number 20 is missing. In this case, the TRAP number assigned to the Set request described later is “19”.

  Further, since the TRAP continuous flag of sequence number 25 of TRAP group number 03 is ON, reception of TRAP group number 03 is not completed. For this reason, the TRAP missing check is not performed. When the continuous TRAP group reception timer (T2 timer (O)) times out in this state, a Get request with the TRAP group number 03 is transmitted to the NE, and a retransmission request for the entire TRAP group is made. Details of these retransmission request operations will be described later.

  The command analysis unit (K) called from the TRAP reception unit (J) will be described with reference to FIGS. The command analysis unit (K) is composed of four processing systems. First, processing when a “TRAP analysis request” (n) is received will be described. When the “TRAP analysis request” (n) is received, it is determined whether the TRAP type is a single TRAP or a continuous TRAP group (11-14), and if it is a single TRAP, the flow shown in FIG. The processing of the flow 11-18 is executed from 11-14. Since the single TRAP process is a normal TRAP process, a description thereof will be omitted.

  When the TRAP to be analyzed is a continuous TRAP group, all TRAP sequence numbers of the TRAP group number are read from the reception TRAP management table (P) (11-1). Next, a TRAP missing check (number continuity check) is performed on the read TRAP sequence number (11-2).

  The presence / absence of TRAP omission is determined (11-3), and when there is no TRAP omission, a “command transmission request” (r) is notified to the command transmission / reception processing unit (M). At that time, an identifier indicating that the command is a Set request transmission request, the latest (oldest number) TRAP sequence number in the TRAP group, and the TRAP group number are assigned.

  After the notification of the “Set request transmission request” (r), the TRAP is transferred to the HMI interface processing unit (L) (s) (11-5), and the TRAP information is displayed on the monitor (Q) as an image. Finally, the TRAP data (TRAP sequence number and TRAP group number) in the reception TRAP management table (P) is cleared (11-6). However, the retrial TRAP sequence number for which reception has been confirmed is not cleared.

  If a TRAP omission is detected, the command transmission / reception processing unit (M) is similarly notified of a “Set request transmission request” (r), but at that time, the TRAP group number and the TRAP sequence number that first confirmed the omission. A TRAP sequence number one before (the last reception is confirmed) is assigned (11-7).

  After the notification by the flow 11-7, the TRAP is transferred (s) to the HMI interface processing unit (L) in the same manner as in the case of no TRAP dropout. The TRAP to be transferred first confirms the dropout. Transfers up to TRAP immediately before the sequence number (last reception confirmed). Thereafter, all TRAP data of the TRAP group in the reception TRAP management table (P) is cleared.

  Next, processing of the command analysis unit (K) when the continuous TRAP group reception timer (T2 timer (O)) times out will be described. The fact that the T2 timer has timed out indicates that the last TRAP of the continuous TRAP group is not received after the lapse of the specified time (T2), and the entire TRAP group including the already received TRAP of the continuous TRAP group is invalidated in the NMS. In order to retransmit the entire TRAP group, a “command transmission request” (r) is notified to the command transmission / reception processing unit (M).

  In order to execute the above processing, the current TRAP group number currently being received is read from the reception TRAP number management table (P) (11-8), and the read TRAP group number (invalid TRAP group number) is used as a command. Stored in the transmission / reception processing unit (M), an identifier indicating that the command of “command transmission request” (r) is a transmission request of the Get request is given, and “Get request transmission request” is notified (11-9). ). Thereafter, all TRAP data of the TRAP group number in the reception TRAP number management table (P) is cleared (11-10).

  Next, the process of the command analysis unit (K) when the T1 timer (N) times out will be described. The T1 timer (N) is started when a Set request is transmitted every time a Set request is transmitted from the NMS, and is stopped when a TRAP is received from the NE. Therefore, the time-out of the T1 timer indicates that no TRAP has been received from the NE even after a predetermined time (T1) has elapsed since the time when the Set request for the previous TRAP reception was transmitted to the NE. .

  Even when the T1 timer times out, a “command transmission request” (r) of Set request transmission for notifying the NE of the current TRAP reception status of the NMS is transmitted to the command transmission / reception processing unit (M). Thereby, the NE can grasp the current TRAP reception status of the NMS, and can confirm the TRAP delivery omission and the connection status with the NMS.

  In order to execute the above processing, the latest TRAP sequence number and the latest TRAP group number are read from the reception TRAP management table (P) (11-11), and the read latest TRAP sequence number and the latest TRAP group number are sent to the command transmission / reception processing unit ( M), and “Set request transmission request” is notified (11-12). At the same time, the T1 timer is started from zero (11-13).

  This process is repeated every time the T1 timer times out until the next time TRAP is received from the NE. When the TRAP is received from the NE, the T1 timer is stopped, and is restarted at the timing when the Set request for the TRAP is transmitted.

  Here, the T1 timer and the T2 timer will be described in detail. The T1 timer monitors the time from the transmission timing of the Set request that the NMS transmits to the NE to the TRAP reception timing, and defines the transmission timing of the autonomous Set request that the NMS transmits to the NE. The T1 timer starts when a Set request is transmitted to the NE, and stops when a TRAP is received from the NE. When the T1 timer times out, a Set request to which the latest value of the TRAP sequence number that has been confirmed to be received at the present time in the NMS is transmitted to the NE. At that time, the T1 timer is started again to monitor TRAP reception.

  FIG. 12 shows a sequence of a normal confirmation operation of NE-NMS communication by T1 timer monitoring. As shown in the figure, when the next TRAP (2) is received from the NE within T1 from the transmission timing of the Set request (1) to TRAP (1), the T1 timer is reset and the TRAP (2) A Set request (2) is transmitted.

  The sequence number of TRAP (2) is assigned to the Set request (2), and the NE receives the Set request (2), and the sequence number assigned to the NE and the latest TRAP sequence number managed by the NE. And confirm that there is no missing TRAP.

  Since there is no TRAP notified from the NE after TRAP (2), the NMS times out the T1 timer after sending the Set request (2). When the T1 timer times out, the NMS transmits a Set request (2) to which the latest TRAP sequence number recognized at the present time is added to the NE. The NE receives the Set request (2), compares the TRAP sequence number assigned to it with the TRAP sequence number transmitted by the NE, and confirms that there is no contradiction. This only confirms the current TRAP sequence number. This operation is repeated every time the T1 timer times out.

  FIG. 13 shows a sequence of an abnormality detection operation for NE-NMS communication by T1 timer monitoring. As shown in the figure, the next TRAP (2) is received from the NE within T1 from the transmission timing of the Set request (1) for TRAP (1), the T1 timer is reset, and the Set request for TRAP (2) is received. (2) is transmitted.

  The sequence number of TRAP (2) is assigned to the Set request (2), and the NE receives the Set request (2), and the sequence number assigned to the NE and the latest TRAP sequence number managed by the NE. And confirm that there is no missing TRAP.

  When the T1 timer times out after the transmission of the Set request (2), the Set request (2) with the latest TRAP sequence number recognized by the NMS at this time is transmitted to the NE. The NE receives the Set request (2), compares the TRAP sequence number assigned to it with the TRAP sequence number transmitted by the NE, confirms that there is no contradiction, and confirms the current TRAP sequence number. .

  Next, NE transmits TRAP (3), but TRAP (3) wants to reach NMS. Then, after transmitting the Set request (2), the NMS transmits the Set request (2) with the TRAP (2) sequence number when the T1 timer times out, and the NE receives the Set request (2). Compared with the sequence number 2 assigned to it and the latest TRAP sequence number 3 managed by the NE, it is recognized that the latest sequence number 3> the received sequence number 2 and TRAP (3) has dropped out. Detect that.

  The NE retransmits the missing TRAP (3). The NMS sends the Set request (3) to which the sequence number of the TRAP (3) is assigned, the NE receives the Set request (3), and the NE sends the TRAP sequence number 3 assigned thereto and the NE Compared with the TRAP sequence number 3 thus confirmed, it is confirmed that the retransmission TRAP (3) has been normally received.

  Next, the continuous TRAP group reception timer (T2 timer (O)) will be described. The T2 timer is a timer that monitors the reception state of the continuous TRAP group, and is started when the first packet of the continuous TRAP group (the packet for which the continuous reception flag is first turned ON) is received. While the continuous reception flag of the continuous TRAP group continues to receive TRAP, the T2 timer is stopped when the TRAP is received, and the T2 timer is started from the cello.

  When the continuous reception flag of the continuous TRAP group changes from ON to OFF (that is, when the final TRAP of the continuous TRAP group is received), the T2 timer is stopped, and the subsequent restart is not performed. The NMS process when the NMS receives the final TRAP and stops the T2 timer is as follows.

(1) When there is no omission in the sequence number of the continuous TRAP group, a “Set request” to which the sequence number of the final TRAP of the continuous TRAP group is added is transmitted to the NE.
(2) If a missing sequence number is found in the sequence number of the continuous TRAP group, the sequence number one last smaller than the youngest sequence number of the missing sequence numbers (the last sequence number normally received continuously) is The assigned “Set request” is transmitted to the NE.

  When the T2 timer times out, the NMS process transmits a “Get request” with a continuous TRAP group number. That is, when the T2 timer does not time out, the continuous TRAP group is received until the final TRAP, and even if there is a dropout of TRAP on the way, the continuous TRAP group itself is treated as being effective, A “Set request” is transmitted to the NE in order to perform only the TRAP retransmission request.

  On the other hand, when the T2 timer times out, the last TRAP of the continuous TRAP group is not received. In this case, the entire continuous TRAP group is treated as invalid, and the entire continuous TRAP group is requested to be retransmitted. , “Get request” is transmitted to NE.

  FIG. 14 shows a sequence of normal confirmation operation of continuous TRAP group reception by T2 timer monitoring. As shown in the figure, the NE recognizes TRAPs (10) to (14) with sequence numbers 10 to 14 as TRAP group numbers 01, and assigns serial numbers 01 to 05 within the group numbers to each TRAP of the TRAP group. Give. Then, the last TRAP can be identified by turning on the continuous flag from the start TRAP of the continuous TRAP group to the TRAP immediately before the last TRAP and turning off the continuous flag of the last TRAP.

  In NMS, T2 is started every time TRAP (10) to (13) is received, all of TRAP (10) to (14) are received within the timeout of T2 timer, and final TRAP (14) is received. Make sure. When the final TRAP (14) is received, the T2 timer is not restarted.

  After receiving the final TRAP (14), the NMS checks for missing TRAP, and if it is determined that there is no missing, sends a Set request with the latest TRAP sequence number 14 and the latest TRAP group number 01-05 to the NE. . The NE compares the TRAP sequence number 14 and TRAP group number 01-05 assigned to the Set request with the latest TRAP sequence number and TRAP group number managed by the NE, and recognizes that there is no omission.

  FIG. 15 shows the sequence of the TRAP missing detection operation for continuous TRAP group reception by T2 timer monitoring. As shown in the figure, the NE recognizes TRAPs (21) to (25) of sequence numbers 21 to 25 as TRAP group number 02, and assigns serial numbers 01 to 05 in the group number to each TRAP of the TRAP group. The continuous flag from the start TRAP (21) of the continuous TRAP group to the TRAP (24) immediately before the final TRAP is turned ON, and the continuous flag of the final TRAP (25) is turned OFF and transmitted.

  Here, it is assumed that TRAP (24) has not reached the NMS. In NMS, except for TRAP (24), TRAP of TRAP group number 02 was received until the final TRAP (25) within the timeout of the T2 timer, so the T2 timer is restarted when the final TRAP (25) is received. The TRAP missing check is performed without detecting that the TRAP (24) is missing.

  The NMS continuously transmits the Set request to which the TRAP (23) of the oldest sequence number received normally and the TRAP group number 02-03 is added to the NE. The NE receives the Set request, compares it with the latest TRAP sequence number and TRAP group number managed by the NE, recognizes that the reception after TRAP (24) has not been confirmed by the NMS, and sets the retransmission TRAP. A Get response to be transmitted later is transmitted to the NMS.

  In the NE, retransmission TRAP generation processing is started, TRAP (24) to TRAP (25) are edited and reproduced as 1TRAP. In the meantime, even if a new event occurs, the TRAP of the event is not included in the reproduction TRAP. This is because the final TRAP of the continuous TRAP group has been received on the NMS side and is treated as an effective continuous TRAP group on the NMS side. Then, the latest retransmission number (26 in this case) is assigned as the sequence number of the one retransmission TRAP and transmitted. Since there is one retransmission TRAP, no continuous flag and TRAP group number are assigned.

  FIG. 16 shows a sequence in the case of a final TRAP missing in continuous TRAP group reception by T2 timer monitoring. As shown in the figure, the NE recognizes the TRAPs (31) to (36) with the sequence numbers 31 to 36 as the TRAP group number 03, and assigns the serial numbers 01 to 06 in the group number to each TRAP of the TRAP group. The continuous flag from the start TRAP (31) of the continuous TRAP group to the TRAP (35) immediately before the final TRAP is turned ON, and the continuous flag of the final TRAP (36) is turned OFF and transmitted.

  Here, it is assumed that TRAPs after TRAP (33) have not reached the NMS. The NMS determines that the reception of the continuous TRAP group is not completed because the T2 timer has timed out without receiving the final TRAP (36), treats the continuous TRAP group as invalid, and sends the TRAP group to the NE collectively. A “Get request” requesting retransmission is transmitted. The “Get request” is transmitted with the TRAP group number 03 added.

  Upon receipt of the “Get request”, the NE recognizes that all TRAPs of TRAP group number 03 have not yet been received, and then transmits a Get response to the retransmission TRAP to the NMS. Then, the NE executes a retransmission TRAP generation process, edits all TRAPs of TRAP group number 03, and reproduces them as one TRAP.

  If a new event occurs during this time, the TRAP of the event is included in the playback TRAP and transmitted together. That is, it does not transmit as a new TRAP. This is because the NMS side does not receive the final TRAP of the TRAP group number 03, discards the previously received TRAP of the TRAP group number 03 as an invalid TRAP group that is not completed as the TRAP group, and newly sets the TRAP group number. This is because all TRAPs of 03 are received again, so that adding a new event TRAP has no effect.

  The NE assigns the latest number (37 in this case) as the retransmission TRAP sequence number, and transmits it. Also in this case, since there is one retransmission TRAP, the continuous flag and the TRAP group number are not given. Note that NMS does not perform re-reception confirmation of retransmission TRAP, and all retransmission TRAP is processed in NMS as new TRAP.

  Next, processing when the NE receives a “Set request” or “Get request” command from the NMS will be described. The processing of the NE side command analysis processing unit (E) will be described with reference to FIGS. First, the case where the received command is a “Set request” will be described.

  First, it is determined whether the received command is a “Set request” (17-1). If the received command is a “Set request”, the continuous TRAP group number assigned to the Set request is checked (17-2). When the TRAP group number is 0, it is determined as a request command for single TRAP, the latest TRAP sequence number managed by the NE is read from the transmitted TRAP holding table (H), and is added to the received “Set request”. Compared with the existing TRAP sequence number, the difference is extracted (17-3).

  Whether there is a difference is determined (17-4). If there is no difference, the TRAP information of the TRAP sequence number in the transmitted TRAP holding table (H) is cleared (17-5), and the command transmission / reception processing unit (D) “Command analysis result (OK)” (j) is notified, and a Get response command is transmitted to the NMS (17-7).

  On the other hand, if there is a difference, it is determined that the difference = the number of missing TRAPs, a TRAP sequence number to be retransmitted and a command type (= Set request) are given, and a “retransmission TRAP generation request” (k) is sent to the retransmission TRAP generation unit (F). ), “Command analysis result (NG)” (j) is notified to the command transmission / reception processing unit (D), and a Get response command is transmitted to the NMS (17-6). No particular processing is performed.

  Returning, when the continuous TRAP group number given to the Set request command is other than 0, it is determined as a request command for the continuous TRAP group, and the latest TRAP group managed by the NE from the transmitted TRAP holding table (H). The latest TRAP sequence number of the number is read out, compared with the continuous TRAP group number and TRAP sequence number given to the “Set request”, and the difference is extracted (17-7).

  The presence / absence of the difference is determined (17-8). If there is no difference, all TRAP information of the TRAP group number in the transmitted TRAP holding table (H) is cleared (17-9), and the command transmission / reception processing unit (D ) Is notified of “command analysis result (OK)” (j), and a Get response command is transmitted to the NMS (17-6).

  On the other hand, if there is a difference, the TRAP group number, the TRAP sequence number to be retransmitted, and the command type (= Set request) are assigned, and a “retransmission TRAP generation request” (k) is notified to the retransmission TRAP generation unit (F). . Further, the NE command transmission / reception processing unit (D) is notified of the “command analysis result (NG)” (j), and a Get response command is transmitted to the NMS (17-10). No particular processing is performed.

  Next, a case where the reception command is “Get request” will be described. In this case, it is determined as a retransmission request for all TRAPs in the continuous TRAP group, and a “retransmission TRAP generation request” in which the continuous TRAP group number and command type (= Get request) are unconditionally assigned to the retransmission TRAP generation unit (F). (K) is notified (17-11).

  Finally, the process of the retransmission TRAP generation unit (F) in the NE will be described with reference to FIG. 1 and FIG. First, it is checked whether the command type assigned to the “retransmission TRAP generation request” (k) is a Set request (18-1). When the command type is “Get request”, the TRAP playback state (I) is shifted to “TRAP playback” (18-2). Thereafter, until the “retransmission TRAP transmission request” (l) is notified to the TRAP transmission unit (C), the process is common to the case where the command type is the Get request and the case where the command type is the Set request.

  Returning, after the command type check, the TRAP information of the sequence number or TRAP group number to be retransmitted attached to the “retransmission TRAP generation request” (k) is read from the transmitted TRAP holding table (H) (18− 3). In the case of single TRAP, the read TRAP information is directly notified to the TRAP transmitter (C) as a “retransmission TRAP transmission request” (l) (18-5). At this time, the old TRAP sequence number is not given.

  When there are a plurality of TRAP information read in the flow 18-3, the TRAP information is edited again as one TRAP information (18-4). When a TRAP is generated by the occurrence of a new event in the NE during editing of the retransmission TRAP, if the TRAP playback state (I) is in the “TRAP playback” state, the new generation is performed from the TRAP transmission unit (C). The “TRAP loading request” (m) to which the TRAP information is added is notified.

  At this time, it is checked in the retransmission TRAP generation unit (F) whether the monitoring item to which the TRAP being edited belongs and the monitoring item to which the TRAP notified by the “TRAP loading request” (m) belongs are the same (18 -7) If the monitoring item is the same, the newly generated TRAP is included in the currently edited TRAP information and re-edited (18-8).

  When the monitoring items are different, the TRAP transmission unit (C) is notified again as a “retransmission TRAP transmission request” (l), but in order to distinguish it from a true retransmission TRAP transmission request, a “retransmission TRAP transmission request” (l ) A return flag is given to the notification (18-9). After the re-editing of the retransmission TRAP information is completed, a “retransmission TRAP transmission request” (l) with the reproduced TRAP is notified to the TRAP transmission unit (C) (18-5), and the command type is “Get request”. In this case, the TRAP playback state (I) is changed to the “normal state” (18-6). While in the “normal state”, the “TRAP loading request” (m) is not notified from the TRAP transmission unit (C).

  19 to 21 show an operation sequence between functional blocks in the NE. FIG. 19A shows a sequence of TRAP transmission processing when the number of generated TRAPs is within the TRAP counter threshold. FIG. 19B shows a sequence of TRAP transmission processing when the number of generated TRAPs exceeds the TRAP counter threshold. FIG. 20 shows a TRAP transmission sequence when a TRAP retransmission request is received by a Set request from the NMS. FIG. 21 shows a TRAP transmission sequence when a TRAP retransmission request is received by a Get request from the NMS.

  22 and 23 show an operation sequence between functional blocks in the NMS. FIG. 22 shows a sequence of retransmission request processing when the final TRAP of the TRAP group is received from the NE before the T2 timer times out. FIG. 23 shows the sequence of the retransmission request process when the T2 timer times out without receiving the final TRAP of the TRAP group from the NE.

  FIG. 24 shows an example of a network configuration to which the present invention is preferably applied. In the configuration example shown in the figure, an NMS is installed in a telephone station A (HUB station), a communication device NE in the telephone station A (HUB station), and a telephone station B and a telephone connected to the NMS via an IP network. This can be suitably applied to a device monitoring network system including the communication device NE in the station C. In the figure, ODU is an out door unit such as an antenna.

It is a figure which shows the structural example of NE of this invention. It is a figure which shows the structural example of NMS of this invention. It is a figure which shows the TRAP production | generation process flow by NE side. It is a figure which shows the example of the TRAP counter value for every unit time in TRAP production | generation. It is a figure which shows the processing flow at the time of the TRAP analysis process and unit time timeout by NE side. It is a figure which shows the structural example of a TRAP distribution holding table. It is a figure which shows the TRAP transmission processing flow by NE side. It is a figure which shows the structural example of the transmitted TRAP holding | maintenance table. It is a figure which shows the TRAP reception processing flow by the side of NMS. It is a figure which shows the structural example of a reception TRAP management table. It is a figure which shows the command analysis processing flow by the side of NMS. It is a figure which shows the sequence of the normal confirmation operation | movement of NE-NMS communication by T1 timer monitoring. It is a figure which shows the sequence of the abnormality detection operation | movement of NE-NMS communication by T1 timer monitoring. It is a figure which shows the sequence of the normal confirmation operation | movement of continuous TRAP group reception by T2 timer monitoring. It is a figure which shows the sequence of the TRAP missing detection operation of continuous TRAP group reception by T2 timer monitoring. It is a figure which shows the sequence in case of last TRAP missing | missing of continuous TRAP group reception by T2 timer monitoring. It is a figure which shows the command analysis process flow by NE side. It is a figure which shows the retransmission TRAP production | generation process flow by NE side. (A) It is a figure which shows the TRAP transmission process sequence in case the number of TRAP is within a threshold value, and (b) the TRAP transmission process sequence in case the number of TRAP is over a threshold value. It is a figure which shows the TRAP transmission sequence in the case of the TRAP resending request | requirement by a Set request. It is a figure which shows the TRAP transmission sequence in the case of the TRAP resending request | requirement by a Get request. It is a figure which shows the resending request | requirement processing sequence when the last TRAP of a TRAP group is received. It is a figure which shows the sequence of the resending request | requirement process when the last TRAP of a TRAP group does not reach | attain. It is a figure which shows the example of the network structure to which this invention is applied suitably.

Explanation of symbols

(1) Monitoring target device (NE)
(2) Network management device (NMS)
(3) IP network (A) TRAP generator (B) TRAP analyzer (C) TRAP transmitter (D) Command transmission / reception processor (E) Command analyzer (F) Retransmit TRAP generator (G) Unit time notification (H) Transmitted TRAP holding table (I) TRAP playback state (J) TRAP receiver (K) Command analyzer (L) HMI interface processor (M) Command transmission / reception processor (N) T1 timer (O ) T2 timer (P) Reception TRAP management table (Q) Monitor

Claims (5)

A network management device having an SNMP manager function and a monitoring target device having an SNMP agent function. The monitoring target device adds a trap sequence number to a trap command and transmits the trap command to the network management device. In the device monitoring network system for receiving the trap and notifying the monitoring target device of the trap sequence number assigned to the received trap,
Generated when the number of traps generated in the monitored device is counted per unit time, the number of traps per unit time is compared with a preset threshold, and the number of traps exceeds the threshold The traps are sorted by monitoring function items, and trap groups are grouped for each monitoring function item. The trap group number assigned to the trap group is added in addition to the trap sequence number and transmitted to the network management device and transmitted. A first means for holding the trap group in the monitored device;
The network management device checks the continuity of traps for each trap group with respect to the received trap, and when there is a trap drop, the trap sequence number and the trap group can be identified. A second means for transmitting a set request command with a number to the monitoring target device;
The monitoring target device analyzes the set request command from the network management device, and holds the trap group number and TRP sequence number of the transmitted trap held internally, and the trap group number assigned to the set request command And the trap sequence number, the missing traps that are not received by the network management device are determined, all the dropped traps are re-edited into one trap, and a new trap sequence number is assigned to the network management. A device monitoring network system comprising: a third means for transmitting to the device and clearing the held transmitted trap. In the second means, the reception status of the trap group is monitored by the continuous trap group reception timer, and when the continuous trap group reception timer times out without receiving the final trap of the trap group, all traps of the trap group are Means for transmitting a get request command to request retransmission of the device to the monitoring target device,
In the third means, the get request command from the network management device is analyzed, all traps of the trap group number requested for retransmission are re-edited into one trap, and a new trap sequence number is assigned. The apparatus monitoring network system according to claim 1, further comprising means for transmitting to the network management apparatus. In the second means, provided with a set request transmission timer that is started every time a set request command is transmitted to the monitoring target device, and is stopped upon reception of the first trap after the transmission of the set request command.
When the set request transmission timer times out, a set request with the latest trap sequence number and the latest trap group number held in the network management device is transmitted to the monitored device, and the set request transmission timer is restarted. The apparatus monitoring network system according to claim 1, further comprising:   In the third means, when a trap is re-edited by a set request command from the network management device, a new trap sequence number different from the retransmission trap is assigned to a newly generated trap during retransmission trap editing. When re-editing traps sent to the network management device and using the get request command from the network management device, traps belonging to the same monitoring item newly generated during trap re-editing are imported into the re-editing trap being edited and re-executed. The apparatus monitoring network system according to claim 2, further comprising means for editing and transmitting to the network management apparatus. Between the network management apparatus having the SNMP manager function and the monitoring target apparatus having the SNMP agent function, the trap target number is assigned to the trap command from the monitoring target apparatus and transmitted to the network management apparatus. In the SNMP trap management method for notifying the monitoring target device of the trap sequence number assigned to the received trap,
Generated when the number of traps generated in the monitored device is counted per unit time, the number of traps per unit time is compared with a preset threshold, and the number of traps exceeds the threshold The traps are sorted by monitoring function items, and trap groups are grouped for each monitoring function item. The trap group number assigned to the trap group is added in addition to the trap sequence number and transmitted to the network management device and transmitted. A first process of holding the trap group in the monitored device,
The network management device checks trap continuity for each trap group with respect to the received trap, and when there is a trap drop, trap information including a trap group number that can identify the dropped trap A second process of transmitting the command to which the command is given to the monitoring target device;
The monitoring target device analyzes the command from the network management device, trap information including the trap group number of the transmitted trap held internally, and trap information including the trap group number assigned to the command Are compared, and the missing traps that are not received by the network management device are determined, all of the dropped traps are re-edited into one trap, and a new trap sequence number is assigned and transmitted to the network management device. And a third step of clearing the held transmitted traps. A method for managing SNMP traps.

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