JP4588652B2 - Connectivity confirmation method - Google Patents

Description

  The present invention relates to a network connectivity confirmation method using a test frame, and more particularly to a connectivity confirmation method in a network composed of bridges that transmit and receive Ethernet (registered trademark) frames based on the IEEE 802 standard.

As a method for confirming connectivity of a network provided by a bridge that transmits and receives an Ethernet frame based on the IEEE 802 standard, the Ethernet OAM Continuity Check described in Non-Patent Document 1 is known. In Non-Patent Document 1, failure detection is realized by periodically transmitting a test frame and confirming its conduction state.
IEEE Draft P802.1ag / D5.2, “Connectivity Fault Management”, Nov 2005

  However, in the method described in Non-Patent Document 1, that is, in the normality confirmation of the route by Ethernet OAM Continuity Check, a test frame is transmitted in units of VLAN (Virtual LAN), so the information on the VLAN ID in the frame is selected. One test frame passes through all the physical lines for the redundant configuration used in the configuration, but as shown in FIG. 11, physical line selection is performed based on information other than the VLAN ID, such as LAG (Link Aggregation). For the redundant configuration, the test frame passes only through one of the physical lines.

  Therefore, when a failure occurs in a physical line through which the test frame does not pass, there is a possibility that the failure is not detected. For this reason, there is a problem that it is determined to be normal although a partial failure has occurred.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a connectivity confirmation method capable of correctly confirming network connectivity and detecting a failure. is there.

  In order to achieve the above object, the present invention is a connectivity confirmation method in a network composed of a bridge having a port for transmitting and receiving a network frame based on a series of IEEE 802 standards, which communicates from a single bridge in the network. Generating a set of test frames that pass through all physical lines leading to another bridge or bridges, wherein the bridges transmit the test frames and the bridge or bridges receive the test frames In the connectivity confirmation method for confirming connectivity between bridges, the set of test frames includes a bridge that transmits test frames or an external device that manages the network, and whether or not there is a redundant configuration in the network. Input frame information in a redundant configuration. Is generated from network configuration information including physical line selection logic information, which is all or part of the correspondence between the input value and the output value of the function with the input value as the input value and the physical line selected as the output value. A frame, a destination MAC address, a plurality of frames that are partly or completely different from the source MAC address, or a frame that encapsulates an IP packet, the destination MAC address, the source MAC address, the destination IP address, the source A plurality of frames in which some or all of the IP addresses are different, or a frame obtained by further encapsulating an IP packet encapsulating a TCP / UDP packet, wherein the destination MAC address, the source MAC address, the destination IP address, and the source IP Address, destination TCP / UDP port Frame, a plurality of frames having different or part of the source TCP / UDP port number, or a frame encapsulating an IPv6 packet, which has a destination MAC address, a source MAC address, a destination IPv6 address, and a source IPv6 address. A plurality of frames that are partially or completely different, or a frame that further encapsulates an IPv6 packet that encapsulates a TCP / UDP packet, that is, a destination MAC address, a source MAC address, a destination IPv6 address, a source IPv6 address, a destination The TCP / UDP port number and the source TCP / UDP port number are partly or entirely composed of a plurality of different frames.

  The network configuration information is preferably set in advance in a bridge or an external device that generates a set of test frames.

  The network configuration information is preferably obtained from a bridge in the network by a bridge or an external device that generates a set of test frames.

  Further, when a VLAN is set in the network, it is preferable to generate the test frame set and transmit / receive the test frame in units of VLANs.

  According to the present invention, it is possible to correctly check connectivity by using a set of test frames that pass through all physical lines, and to detect a failure when a failure occurs in the network. Become.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a network configuration that provides the function of the connectivity confirmation method of the present invention. The network is composed of bridges A, B, C, D, E, and F and physical lines 101 to 108 connecting them. There is also an external device that manages this network.

  The redundant configuration 1001 includes a physical line 101 and a physical line 102, and a frame transferred from the bridge A is transferred by selecting the physical line 101 or the physical line 102 using information in the frame. The redundant configuration 1002 includes a physical line 103 and a physical line 104, and a frame transferred from the bridge B to the bridge D is transferred by selecting the physical line 103 or the physical line 104 using information in the frame. . The frame transferred from the bridge D to the bridge B is transferred by selecting the physical line 103 or the physical line 104 using the information in the frame. The redundant configuration 1003 includes a physical line 105 and a physical line 106, and a frame transferred from the bridge C to the bridge E is transferred by selecting the physical line 105 or the physical line 106 using information in the frame. . The frame transferred from the bridge E to the bridge C is transferred by selecting the physical line 105 or the physical line 106 using information in the frame. The redundant configuration 1004 includes a physical line 107 and a physical line 108, and a frame transferred from the bridge F is transferred by selecting the physical line 107 or the physical line 108 using information in the frame.

  The bridges A and F are set to use the VLAN ID for physical line selection, the bridges B and D are set to use the destination IP (Internet Protocol) address for physical line selection, and the bridges C and E are The transmission source TCP port number is set to be used.

  The physical line selection in each bridge is set as shown in FIG. That is, when the low-order bit of the field value used for physical line selection is 0, a physical line with a large port number is selected, and when it is 1, a physical line with a small port number is selected. A VLAN is set for this network, and the set VLAN IDs are 1001, 1002, 1003, and 1004.

  In this embodiment, a case where the connectivity between the bridges A and F is confirmed will be described. The external device grasps the configuration of the network, and calculates a delivery route for each VLAN as shown in FIG. 2 from the network configuration information set in advance.

  In the case of VLAN = 1001, there are two paths from the bridge A to the bridge F, and the first path of the bridge A-physical line 101-bridge B-physical line 103-bridge D-physical line 107-bridge F; The second route is bridge A-physical line 101-bridge B-physical line 104-bridge D-physical line 107-bridge F.

  The external apparatus generates a frame encapsulating an IP packet having VLAN ID = 1001 and destination IP address = 192.168.0.1 as a test frame for selecting the first path, and the second path As a test frame for selecting, a frame encapsulating an IP packet having VLAN ID = 1001 and destination IP address = 192.168.0.2 is generated. FIG. 9 is a diagram illustrating an example of a frame format of a test frame for selecting a first route, and FIG. 10 is a diagram illustrating an example of a frame format of a test frame for selecting a second route.

  Here, there is a redundant configuration in the VLAN = 1001 network, and as the physical line selection logic information of the redundant configuration, input frame information (here, the destination IP address) is used as an input value, and the physical line to be selected is Since the input value of the function to be the output value and the information on all the correspondence relations of the output value are known, this is a frame encapsulating the IP packet, and the destination IP address covering two routes is arbitrarily selected and different If a test frame is composed of two frames, but no redundant configuration exists in the network, the test frame set is composed of one frame. If a redundant configuration exists, input frame information in the redundant configuration is input. All or part of the correspondence between the input value and the output value of the function whose output value is the selected physical line It must be generated from the network configuration information including the physical line selection logic information which is information.

  Therefore, a set of test frames is a single frame, or a destination MAC address, a plurality of frames that are partly or completely different from the source MAC address, or a frame that encapsulates an IP packet. Multiple frames with different original MAC address, destination IP address, or source IP address or frames that further encapsulate TCP (Transmission Control Protocol) / UDP (User Datagram Protocol) packets Destination MAC address, source MAC address, destination IP address, source IP address, destination TCP / UDP port number, source TCP / UDP port number A plurality of frames that are partly or completely different from each other, or a frame in which an IPv6 (Internet Protocol Version 6) packet is encapsulated, and a destination MAC address, a source MAC address, a destination IPv6 address, a part of a source IPv6 address or A plurality of frames different from each other or a frame obtained by further encapsulating an IPv6 packet encapsulating a TCP / UDP packet, which is a destination MAC address, a source MAC address, a destination IPv6 address, a source IPv6 address, and a destination TCP / UDP There are cases where a part or all of the port number and the source TCP / UDP port number are composed of a plurality of different frames.

  In the case of VLAN = 1002, 1003, 1004, a test frame set is generated in the same manner, and the generated test frame set is set in the transmission test frame table of bridge A as shown in FIG.

  Similarly, in the case of the route from the bridge F to the bridge A, a route is calculated for each VLAN, a set of test frames passing through all physical lines is generated, and the set of generated test frames is a bridge as shown in FIG. Set to F transmission test frame table.

  In the above-described embodiment, the external device that manages the network generates a set of test frames from the network configuration information. However, the network configuration information is set in advance in the bridge that transmits the frame, and the frame May generate a set of test frames from the configuration information of the network.

  The bridge A periodically transmits a test frame based on the set transmission test frame table. Similarly, the bridge F periodically transmits test frames based on the set transmission test frame table.

  When the bridge F receives the test frame from the bridge A, as shown in FIG. 6, the transmission source bridge, VLAN ID, destination IP address, transmission source TCP port number, and last reception time of the frame are stored in the reception test frame table. Remember. Similarly, when the test frame from the bridge F is received, the bridge A stores the test frame in the reception test frame table as shown in FIG.

  When the bridge F has received all the test frames from the bridge A within the preset time from the last reception time as in the reception test frame table shown in FIG. It can be confirmed that the entire route is normal. As shown in the reception test frame table shown in FIG. 5, when the bridge A receives all the test frames from the bridge F within a preset time from the last reception time, It can be confirmed that the entire route toward A is normal. The connectivity between the bridge A and the bridge F can be confirmed by combining the two.

  On the other hand, when the physical line 103 fails and the line is disconnected, among the test frames transmitted from the bridge A, an IP packet having VLAN ID = 1001, 1003 and destination IP address = 192.168.0.1 is selected. The encapsulated test frame does not reach the bridge F. As shown in the table of FIG. 8, the bridge F receives the test frame within a preset time from the last reception time of the test frame with VLAN ID = 1001, 1003 and destination IP address = 192.168.0.1. Therefore, it is determined that a failure has occurred. In this case, since a part of the test frame transmitted from the bridge A does not arrive, it is determined that a failure has occurred in the delivery path from the bridge A to the bridge F.

  Similarly, among the test frames transmitted from the bridge F, a test frame encapsulating an IP packet having VLAN ID = 1001, 1003 and destination IP address = 192.168.0.1 does not reach the bridge A. As shown in the table of FIG. 7, the bridge A receives the test frame within a preset time from the last reception time of the test frame with VLAN ID = 1001, 1003 and destination IP address = 192.168.0.1. Therefore, it is determined that a failure has occurred.

  In the present embodiment, a case has been described in which the external device grasps the network configuration in advance. However, the external device may acquire configuration information from a bridge MIB (Management Information Base) in the network. The external device may log in to the bridge using a protocol such as TELNET and obtain configuration information from the command line, or the external device does not exist and the test frame transmission bridge preliminarily stores the network configuration information. Alternatively, the test frame transmission bridge may acquire the network configuration information from the MIB of the bridge in the network.

  In this embodiment, the test frame is a unicast frame. However, the test frame may be a unicast frame in which the destination bridge is designated, or a multicast frame or a broadcast frame in which no destination bridge is designated. A unicast frame whose destination has not been learned may be used.

It is a figure which shows the network structure which provides the function of the network connectivity confirmation method of this invention. It is a figure which shows the example of calculation of the delivery path | route of VLAN unit. FIG. 4 is a diagram illustrating an example of a transmission test frame table for bridge A. 6 is a diagram illustrating an example of a transmission test frame table of a bridge F. FIG. It is a figure which shows an example of the transmission test frame table of the bridge A when a delivery path | route is normal. It is a figure which shows an example of the transmission test frame table of the bridge F when a delivery path | route is normal. It is a figure which shows an example of the transmission test frame table of the bridge A when a delivery path | route has failed. It is a figure which shows an example of the transmission test frame table of the bridge F when a delivery path | route has failed. It is a figure which shows an example of the frame format of the test frame which selects a 1st path | route. It is a figure which shows an example of the frame format of the test frame which selects a 2nd path | route. It is a figure explaining the normality confirmation of the path | route by Continuity Check of Ethernet OAM.

Explanation of symbols

101-107 Physical line 1001-1004 Redundant configuration

Claims (4)

A method for confirming connectivity in a network composed of bridges having ports for transmitting and receiving network frames based on a series of IEEE 802 standards, from a single bridge of the network to another single or multiple bridges communicating Generate a set of test frames that pass through all physical lines, the single bridge transmits the test frame, and the bridge or bridges receive the test frame to confirm connectivity between the bridges In the connectivity check method,
The set of test frames is selected by using the input frame information in the redundant configuration as the input value when the bridge transmitting the test frame or the external device managing the network has a redundant configuration in the network and the redundant configuration exists. Generated from network configuration information including physical line selection logic information, which is all or part of the correspondence between input values and output values of functions whose output values are physical lines
A single frame,
Or a plurality of frames in which some or all of the destination MAC address and source MAC address are different,
Or a frame that encapsulates an IP packet, and a plurality of frames in which a destination MAC address, a source MAC address, a destination IP address, a part or all of the source IP address are different,
Alternatively, a frame obtained by further encapsulating an IP packet encapsulating a TCP / UDP packet, which is a destination MAC address, a source MAC address, a destination IP address, a source IP address, a destination TCP / UDP port number, a source TCP / Multiple frames with different or part of the UDP port number,
Or a frame in which an IPv6 packet is encapsulated, and a plurality of frames in which a destination MAC address, a source MAC address, a destination IPv6 address, a part of or all of the source IPv6 addresses are different,
Alternatively, it is a frame obtained by further encapsulating an IPv6 packet encapsulating a TCP / UDP packet, which is a destination MAC address, a source MAC address, a destination IPv6 address, a source IPv6 address, a destination TCP / UDP port number, a source TCP / Multiple frames with different or part of the UDP port number,
A method for confirming connectivity, comprising:   The connectivity confirmation method according to claim 1, wherein the network configuration information is preset in a bridge or an external device that generates a set of test frames.   The connectivity confirmation method according to claim 1, wherein the network configuration information is acquired from a bridge in the network by a bridge or an external device that generates a set of test frames.   The connectivity check according to any one of claims 1 to 3, wherein when a VLAN is set in the network, the test frame set is generated and the test frame is transmitted and received in VLAN units. Method.

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