JP2015211247A - Network device and network system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To notify a network device of an alarm indicating mismatch, when the relationship of PHY setting and Sync-E setting do not match.SOLUTION: A network device 10 includes a physical layer device 13 connected with a synchronous network system 1 operating in synchronism with a predetermined clock, and performing master/slave setting of Sync-E and master/slave setting of PHY, and an alarm detector 15 for monitoring the master/slave setting of Sync-E and master/slave setting of PHY, and detecting whether or not the setting matches. The alarm detector 15 notifies the network device 10 of an alarm, when detecting mismatch of setting.

Description

  The present invention relates to a network device and a network system, and more particularly to a device and system for notifying an alarm to a network device when a setting abnormality is detected.

  Currently, transmission network used in a carrier network is a line-based network network mainly for providing fixed telephones and dedicated line services, and IP (Internet Protocol) such as the Internet and Ethernet (registered trademark) dedicated lines. There are packet-based networks for providing system services.

  These two networks are independent of each other, and need to be individually maintained and managed. Therefore, it is desired to efficiently accommodate the two networks on the same network in order to improve equipment efficiency.

  In order to meet such a demand, in recent years, a technique called packet transport has emerged that accommodates a line-based network in a packet-based network with low cost and high accommodation efficiency.

  For example, an SDH (Synchronous Digital Hierarchy) network, which is a typical line-based network, is premised on network synchronization when performing communication. On the other hand, the Ethernet network, which is a typical packet-based network, does not require network synchronization when performing communication. Therefore, in order to accommodate the SDH network in the Ethernet network, a mechanism for synchronizing the network is also required in the Ethernet network. That is, in order to realize the above-described packet transport, a network synchronization function is required.

  Therefore, “Sync-E (Synchronous-Ethernet)”, which is a technique for performing synchronization in the Ethernet network, is an ITU-T (International Telecommunication Union-Telecommunication Standardization Sector) recommendation G. 8261, standardized.

  Sync-E is a method of performing synchronization by sharing a clock used in the network. In this method, a clock is supplied from a master port of a reference network device to a slave port of another network device connected via Ethernet. Then, the network device that has received the clock supplies the clock to another network device. In this way, a plurality of network devices connected to each other can be connected in a daisy chain to synchronize the network.

  By the way, for example, a standard of a physical layer device (hereinafter referred to as “PHY (PHYsical layer)”) called “1000BASE-T” exists in the Ethernet interface, and IEEE (Institute of Electrical and Electronic Engineers) 802.3ab. It is stipulated in. This standard refers to the operation of auto-negotiation that appropriately determines the link speed and half duplex / full duplex in communication between 1000BASE-T PHYs. In addition to the items described above, the master / slave relationship at the data transmission / reception timing between PHYs is determined.

  In 1000BASE-T, it is defined that data is transmitted and received on the same signal line, and it is necessary to separate transmitted and received signals. Therefore, a parent-child relationship (master / slave) is set between the interfaces, and the transmission / reception signal is separated by synchronizing the data transmission / reception timing of the slave PHY with the data transmission / reception timing of the master PHY.

  In a general PHY, this master / slave setting is performed by a setting called Advertise mode, and any one of four types of Auto (Repeater), Auto (DTE), Manual (Master), and Manual (Slave) is set. use.

  For example, when two PHYs are used as a pair of Auto (Repeater) and Auto (DTE), the Auto (Repeater) side uniquely becomes the PHY master. On the other hand, when two PHYs are used as a pair of Auto (Repeater) and Auto (Repeater), or a pair of Auto (DTE) and Auto (DTE), one of them becomes a master by auto-negotiation and uniquely The master of PHY cannot be decided. When Manual (Master) and Manual (Slave) are used, the setting is fixed as set.

  Usually, when a network device having a PHY of 1000BASE-T uses a network synchronization function such as Sync-E, the relationship between the PHY master / slave in each port and the master / slave in Sync-E The relationship needs to be matched.

  In an existing network device, a method is generally used in which a master / slave setting of Sync-E is set by a user operation, and a master / slave setting of PHY is linked to the setting of Sync-E. That is, when the Sync-E setting is the master, PHY is set to Auto (Repeater), and when the Sync-E setting is the slave, PHY is set to Auto (DTE). Thereby, the parent-child relationship of Sync-E and PHY is made to correspond.

  By the way, if ports with Sync-E set as slaves are connected due to misconfiguration, etc., PHY gives priority to connectivity, so the auto-negotiation setting ignores the match state, and one becomes the master. The other is automatically set as a slave. As a result, in one of the connected ports, a mismatch state occurs in which the PHY setting is the master and the Sync-E setting is the slave, and the synchronization function does not operate normally.

  In such a case, in the synchronous network system using the conventional Sync-E, the relationship between the PHY master / slave and the master / slave in the Sync-E due to the incorrect setting or incorrect connection of the Sync-E in the network device. There is a problem that it is not possible to quickly detect a discrepancy with the relationship.

  This is because, as described above, the Ethernet network does not require network synchronization, so it appears that the devices in which the two are inconsistent do not lose Ethernet frames and can communicate normally. Because it ends up.

  Therefore, when the SDH network is accommodated in the Ethernet network by the packet transport, the network operator recognizes the failure for the first time due to the loss of the SDH signal. However, even if the network operator can recognize the failure by the loss of the SDH signal, it is difficult to determine which device connected to the Ethernet network has the problem.

  Therefore, a method for preventing such a mismatch between the PHY master / slave relationship and the master / slave relationship in Sync-E has been proposed. For example, Patent Document 1 discloses a relationship between PHY and Sync-E by fixing the auto-negotiation setting to a slave for a port PHY whose Sync-E setting of the network device is a slave. Describes a technique for preventing the occurrence of a mismatch.

JP 2012-222524 A

  However, in the method described in Patent Document 1, in a device in which the setting of Sync-E is a slave, since the setting of PHY is always a slave, a mismatch does not occur between Sync-E and PHY. For example, when ports whose Sync-E settings are set to slaves are connected, there is a problem in that normal communication cannot be performed between connected devices.

  In such a case, it is possible to detect that an abnormality has occurred in the device because the connection cannot be established. However, since the connection is disconnected, the network administrator is informed of the abnormality. An alarm cannot be notified.

  In addition, a method of notifying an alarm to a network device having a port in which a mismatch has occurred between Sync-E and PHY can be considered. However, if the Sync-E setting is incorrect in the network device in which a mismatch has occurred. For example, there is a possibility that a mismatch occurs due to an incorrect setting of Sync-E in the network device of the connection destination. For this reason, it is necessary to notify the alarm not only to the device in which the mismatch between Sync-E and PHY occurs, but also to the network device to which the Sync-E is connected.

  Therefore, the present invention has been made in view of the above-described problems in the prior art, and there is a discrepancy between the PHY master / slave relationship and the Sync-E master / slave relationship. An object of the present invention is to provide a network device and a network system that detect the mismatch and notify an alarm indicating the mismatch to the network device.

  In order to achieve the above object, the present invention is a network device connected to a synchronous network system that operates in synchronization with a predetermined clock, and performs Sync-E master / slave setting and PHY master / slave setting. A physical layer device; and an alarm detection unit that monitors the Sync-E master / slave setting and the PHY master / slave setting, and detects whether the settings match, and the alarm detection unit includes: An alarm is notified to the network device when a setting mismatch is detected.

  Further, the present invention is a synchronous network system in which a plurality of network devices that operate in synchronization with a predetermined clock and are connected in series, wherein the network device includes a Sync-E master / slave setting and a PHY A physical layer device that performs master / slave setting, and an alarm detection unit that monitors the Sync-E master / slave setting and the PHY master / slave setting, and detects whether the settings match, The alarm detection unit notifies the network device of an alarm when the mismatch of the settings is detected.

  As described above, according to the present invention, when a mismatch occurs between the PHY master / slave relationship and the Sync-E master / slave relationship, the mismatch is detected and connected. An alarm indicating a mismatch can be notified to the previous network device.

1 is a block diagram showing an embodiment of a network system according to the present invention. It is a block diagram which shows one Embodiment of the network device which concerns on this invention. It is a block diagram for demonstrating the case where the setting of Sync-E and the setting of PHY are abnormal. It is a block diagram for demonstrating the method to judge the state of the relationship of the setting of Sync-E, and the relationship of the setting of PHY.

  Next, an embodiment for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an embodiment of a network system according to the present invention. In this network system 1, a plurality of network devices 10A, 10B,... Are provided on a PSN (Packet Switched Network) 20 and adjacent to each other. The network devices 10 are configured to be connected in series with each other. In this example, the network device 10A serves as a master for generating a reference clock, and a clock is supplied from the network device 10A to the network device 10 (slave) after the network device 10B.

  As shown in FIG. 2, the network device 10 includes a clock source 11, a PLL (Phase Locked Loop) circuit 12, physical layer devices (hereinafter referred to as “PHY”) 13_1 and 13_2, connection interfaces (hereinafter referred to as “connection I / F”). 14_1 and 14_2, and an alarm detector 15. In the following description, when it is not necessary to distinguish between PHYs 13_1 and 13_2, they are simply referred to as PHY13. Similarly, the connection I / Fs 14_1 and 14_2 are referred to as connection I / Fs 14 and described.

  The network device 10 synchronizes with a master that supplies a reference clock for synchronizing each network device 10 to another network device 10 and a clock supplied from the other network device 10 by a network operator. Is set in advance to one of the slaves that operate.

  The clock source 11 generates a clock serving as a reference clock when the device itself is set as a master, and outputs the generated clock to a PLL circuit 12 described later. The clock source 11 does not generate a clock when its own device is set as a slave.

  The PLL circuit 12 supplies the clock supplied from the clock source 11 to each device provided in the network apparatus 10. The PLL circuit 12 outputs the clock supplied from the clock source 11 to the PHY 13 when the own device is set as the master. On the other hand, the PLL circuit 12 outputs a clock to the PHY 13_2 or 13_1 in synchronization with the clock supplied from the PHY 13_1 or 13_2 when the own device is set as a slave.

  The PHY 13 outputs the clock supplied from the PLL circuit 12 to the connection I / F 14 and outputs the clock supplied from the connection I / F 14 to the PLL circuit 12.

  In PHY 13, Sync-E setting and PHY setting are performed, and Sync-E setting (master / slave) is performed in accordance with a setting state (master / slave) of connection I / F 14 described later. At the same time, Advertise settings (Auto (Repeater) / Auto (DTE)) are performed in accordance with the Sync-E settings. Then, PHY settings (master / slave) are performed by auto-negotiation based on the relationship with the Advertise settings in other connected network devices 10.

  Specifically, when the connection I / F 14 is set as a master, Sync-E is set as a master, Advertise is set as Auto (Repeater), and the connection I / F 14 is set as a slave. In this case, Sync-E is set as a slave and Advertise is set as Auto (DTE).

  Then, PHY is set based on the setting of Advertise in the own device and the setting of Advertise in the other connected network device 10. As described in the background art section, the PHY setting in this case is such that when used as a pair of Auto (Repeater) and Auto (DTE), the Auto (Repeater) side becomes the PHY master. In addition, when used as a pair of Auto (Repeater) or a pair of Auto (DTE), one of them becomes a master and the other becomes a slave by auto-negotiation.

  The connection I / F 14 has two Ethernet ports, a master port and a slave port. The connection I / F 14 is connected to a connection I / F 14 provided in another adjacent network device 10 to perform bidirectional data communication and master to slave. Give and receive clocks. When the connection I / F 14 is set as a master, the connection I / F 14 outputs the clock supplied from the PHY 13 to the other connected network devices 10 using the master port. On the other hand, when the connection I / F 14 is set as a slave, the connection I / F 14 outputs a clock supplied from another connected network device 10 using the slave port to the PHY 13.

  When the network device 10 is set to either the master or the slave, the connection I / F 14 is set to either the master or the slave by the network operator corresponding to the setting. Specifically, when the network device 10 is set as the master, the connection I / F 14 is set as the master, the master port is used, and when the network device 10 is set as the slave, the connection I / F is set. F14 is set as a slave and the slave port is used.

  The alarm detection unit 15 monitors the Sync-E setting and the PHY setting in the PHY 13, determines the relationship between them, and generates alarm information when it detects a mismatch, Output to the alarm detection unit 15 of the connected network device 10.

  For example, the alarm information may be output at a predetermined interval while a mismatch is detected. Further, for example, when the network device 10 has a function of holding an alarm, it may be output when the state changes.

  In addition, when the alarm detection unit 15 stops detecting a mismatch between the Sync-E setting and the PHY setting, the alarm detection unit 15 cancels the alarm notification and disconnects the two network devices 10 connected to each other. Also cancel the alarm notification.

  This means that the recovery notification from the mismatch is not performed to the alarm detection unit 15 of the network device 10 connected from the alarm detection unit 15, and the release from the alarm is autonomously performed in each network device 10. Shall be.

  Here, for example, an alarm notification frame can be used as the alarm information for the network device 10 connected to the own device. This alarm notification frame is an Ethernet frame, and UDP (User Datagram Protocol) is used for the transport layer.

  It should be noted that the data area of the alarm notification frame can be distinguished from frames other than this frame, and it can be recognized that an alarm indicating inconsistency has occurred in the connected network device 10.

  Next, the operation of the network system 1 having the above configuration will be described.

  First, in the network system 1 including a plurality of connected network devices 10, a case where the Sync-E setting and the PHY setting in the two network devices 10A and 10B are normal will be described with reference to FIG. To do. The example illustrated in FIG. 1 illustrates a case where the network device 10A is set as a master and the network device 10B is set as a slave. In this example, in order to prevent the explanation from becoming complicated, the illustration of the portions that are not necessary for the explanation of the operation is omitted.

  In the network device 10A, the network operator sets the device and the connection I / F 14A_1 as a master. When the connection I / F 14A_1 is set as the master, the PHY 13A_1 sets Sync-E as the master and sets Advertise to Auto (Repeater).

  On the other hand, in the network device 10B, the network operator sets the device and the connection I / F 14B_2 as a slave, and sets the connection I / F 14B_1 as a master. When the connection I / F 14B_2 is set as a slave, the PHY 13B_2 sets Sync-E as a slave and sets Advertise to Auto (DTE). Further, when the connection I / F 14B_1 is set as the master, the PHY 13B_1 sets Sync-E as the master and sets Advertise to Auto (Repeater).

  When the two network devices 10A and 10B set in this way are connected via the connection I / Fs 14A_1 and 14B_2, the PHYs 13A_1 and 13B_2 mutually confirm the setting of the Advertise in the connection destination PHY 13. In this case, since the Advertise setting is a pair of Auto (Repeater) and Auto (DTE), the PHY 13A_1 sets the PHY to the master by auto-negotiation. The PHY 13B_2 sets the PHY as a slave by auto-negotiation.

  Next, in the network device 10A set as the master, the clock source 11A generates a reference clock and supplies it to the PLL circuit 12A. The PLL circuit 12A supplies the clock supplied from the clock source 11A to each device in the network apparatus 10A and also supplies it to the PHY 13A_1. The PHY 13A_1 outputs the clock supplied from the PLL circuit 12A to the network device 10B via the connection I / F 14A_1.

  In the network device 10B, the clock source 11B does not generate a clock because the network device 10B is set as a slave. The PHY 13B_2 receives a clock from the network device 10A via the connection I / F 14B_2 and supplies the clock to the PLL circuit 12B. The PLL circuit 12B supplies the clock supplied from the PHY 13B_2 to each device in the network device 10B and also supplies it to the PHY 13B_1. The PHY 13B_1 outputs the clock supplied from the PLL circuit 12B to the next network device 10 connected via the connection I / F 14B_1.

  Hereinafter, the clock generated in this way by the clock source 11A of the network device 10A is sequentially supplied to the next network device 10 connected in a daisy chain. Thereby, the network device 10 connected in a daisy chain can be synchronized with the network device 10A.

  In this case, since the relationship between the Sync-E settings in the network devices 10A and 10B matches the relationship between the PHY settings, the alarm detection units 15A and 15B (not shown) send an alarm notification. Not performed.

  Next, in the network system 1 including a plurality of connected network devices 10, the case where the Sync-E setting and the PHY setting in the two network devices 10A and 10B are abnormal is described with reference to FIG. explain. The example shown in FIG. 3 shows a case where the network device 10A is set as a master and the network device 10B is scheduled to be set as a slave, and the network device 10A is set as a slave due to misconfiguration by the network operator. In this example, as in the description of FIG. 1, in order to prevent the description from becoming complicated, illustration of portions that are not necessary for the description of the operation is omitted.

  In the network device 10A, the network operator sets the device and the connection I / F 14A_1 as slaves. When the connection I / F 14A_1 is set as a slave, the PHY 13A_1 sets Sync-E as a slave and sets Advertise to Auto (DTE).

  On the other hand, in the network device 10B, the network operator sets the device and the connection I / F 14B_2 as a slave, and sets the connection I / F 14B_1 as a master. When the connection I / F 14B_2 is set as a slave, the PHY 13B_2 sets Sync-E as a slave and sets Advertise to Auto (DTE). Further, when the connection I / F 14B_1 is set as the master, the PHY 13B_1 sets Sync-E as the master and sets Advertise to Auto (Repeater).

  When the two network devices 10A and 10B set in this way are connected via the connection I / Fs 14A_1 and 14B_2, the PHYs 13A_1 and 13B_2 mutually confirm the setting of the Advertise in the connection destination PHY 13. In this case, since the setting of Advertise is a pair of Auto (DTE), PHYs 13A_1 and 13B_2 set one PHY as a master and the other PHY as a slave by auto-negotiation.

  At this time, which PHY is set as the master is determined by, for example, a seed value that is a unique value of each PHY 13A_1 and 13B_2, and the PHY 13 with the higher (or lower) seed value is set as the master. Is set. In this example, it is assumed that PHY13B_2 is set as a master and PHY13A_1 is set as a slave by auto-negotiation.

  In this case, the network device 10A set as a slave does not generate a clock by the clock source 11A. The PHY 13A_1 receives a clock from the network device 10B via the connection I / F 14A_1 and supplies the clock to the PLL circuit 12A. The PLL circuit 12A supplies the clock supplied from the PHY 13A_1 to each device in the network device 10A. That is, the network device 10A operates in synchronization with the network device 10B because the clock is supplied from the network device 10B.

  On the other hand, in the network device 10B, the PHY 13B_2 supplies a clock to the PLL circuit 12B because the network device 10B is set as a slave. The PLL circuit 12B supplies the clock supplied from the PHY 13B_2 to each device in the network device 10B and also supplies it to the PHY 13B_1. The PHY 13B_1 outputs the clock supplied from the PLL circuit 12B to the next network device 10 connected via the connection I / F 14B_1.

  At this time, since the PHY 13B_2 is not supplied with any clock, the network device 10B does not synchronize with any network device 10 and enters a free-run state.

  Therefore, when the network device 10A is set incorrectly and the Sync-E setting and the PHY setting are abnormal, all the network devices 10 in the system are synchronized with the network device 10B. However, since the network device 10B does not operate based on the clock from the clock source 11B that generates a highly accurate clock, the entire network operates at a clock timing with low accuracy, and the network system does not operate normally.

  Therefore, in this embodiment, in such a case, the state of the relationship between the Sync-E setting and the relationship with the PHY setting in the network devices 10A and 10B is indicated by the alarm detection units 15A and / or 15B (not valid). (Not shown), it is detected that these relationships are inconsistent, and an alarm is notified.

  Next, an operation for determining the state between the Sync-E setting relationship and the PHY setting relationship will be described with reference to FIG. In the example shown in FIG. 4, as in FIG. 3, the network device 10A is set as the master, and the network device 10B is set as the slave, and the network device 10A is set as the slave due to the network operator's misconfiguration. Show the case. In this example, in order to prevent the explanation from becoming complicated, the illustration of the portions that are not necessary for the explanation of the operation is omitted.

  First, the alarm detection unit 15A provided in the network device 10A monitors the Sync-E setting and the PHY setting in the PHY 13A_1, and determines the relationship between them. In this example, since the Sync-E setting in the PHY 13A_1 is a slave and the PHY setting is a slave, the relationships are matched, so that the setting is determined to be normal and no alarm notification is performed.

  On the other hand, the alarm detection unit 15B provided in the network device 10B monitors the Sync-E setting and the PHY setting in the PHY 13B_2, and determines the relationship between them. In this example, since the setting of Sync-E in PHY 13B_2 is a slave and the setting of PHY is a master, the relationships do not match. Therefore, the alarm detection unit 15B determines that the setting is abnormal, generates alarm information, and notifies the own device of the alarm.

  By the way, between the network devices 10A and 10B connected to each other, the setting abnormality does not always occur in the network device 10B that is the own device, but may also occur in the connected network device 10A. . This is because the settings of the network devices 10A and 10B are determined in relation to the connected network device 10A.

  For example, in the example shown in FIG. 3, the alarm detection unit 15A determines that the setting in the network device 10A is normal, but actually, the setting of the network device 10A is erroneously set. In such a case, even if an alarm is notified only to the network device 10B, the network operator cannot find an abnormality.

  Therefore, in the present embodiment, the alarm is notified not only to the network device 10 that has detected the abnormality, but also to the network device 10 connected to the network device 10 that has detected the abnormality. Thereby, it is possible to notify the network operator that the network device 10 that has detected the abnormality or the network device 10 connected to the network device 10 has an incorrect setting, and quickly find the abnormal part. be able to.

  That is, when the alarm detection unit 15B determines that the relationship between the Sync-E setting and the PHY setting does not match, the alarm detection unit 15B notifies the network device 10B of an alarm and also notifies the network device 10A. Notify the alarm.

  The alarm notified from the alarm detection unit 15B to the network device 10A is detected by the alarm detection unit 15A, and the alarm detection unit 15A notifies the network device 10A of the alarm so that the network operator can recognize it. The alarm at this time can be distinguished from the alarm notified by the network device 10B so that it can be understood that an abnormality has been detected by the network device 10B.

  As described above, according to the present embodiment, when it is determined that the relationship between the Sync-E setting and the PHY setting is inconsistent, an alarm is notified to the own apparatus and the connection is established. An alarm is also notified to other network devices. As a result, an alarm can be notified without disconnecting the network layer replacement, and the network operator can easily recognize that the setting of the device is incorrect, and cope with the erroneous setting. can do.

  In addition, since alarms for the own device and connected devices can be distinguished, it is possible to easily determine in which device an erroneous setting has occurred based on the notified alarm, and to quickly deal with the erroneous setting. be able to.

1 Network system 10 (10A, 10B) Network device 11 (11A, 11B) Clock source 12 (12A, 12B) PLL circuit 13 (13_1, 13_2, 13A_1, 13B_1, 13B_2) Physical layer device 14 (14_1, 14_2, 14A_1) 14B_1, 14B_2) Connection interface 15 (15A, 15B) Alarm detector 20 PSN

Claims (4)

A network device connected to a synchronous network system that operates in synchronization with a predetermined clock,
A physical layer device for performing Sync-E master / slave setting and PHY master / slave setting;
An alarm detection unit that monitors the master-slave setting of the Sync-E and the master / slave setting of the PHY, and detects whether the settings match,
The network device according to claim 1, wherein the alarm detection unit notifies the network device of an alarm when the setting mismatch is detected.   The network device according to claim 1, wherein the alarm detection unit notifies an alarm to another network device connected to the network device when the setting mismatch is detected.   The network device according to claim 2, wherein the alarm detection unit notifies an alarm for the network device and an alarm for the other network device in a distinguishable manner. A synchronous network system in which a plurality of network devices operating in synchronization with a predetermined clock are connected in series,
The network device is:
A physical layer device for performing Sync-E master / slave setting and PHY master / slave setting;
An alarm detection unit that monitors the master-slave setting of the Sync-E and the master / slave setting of the PHY, and detects whether the settings match,
The network system according to claim 1, wherein the alarm detection unit notifies the network device of an alarm when the setting mismatch is detected.

Images