Method, system and device for realizing flow load sharing among multiple MST domains

Abstract

The invention provides a method, system and device for realizing flow load sharing among a plurality of MST domains, and the method comprises the steps: configuring the same VLAN (Virtual Local Area Network) division scheme for all switching equipment of the plurality of MST domains in an MSTP (Multiple Spanning Tree Protocol) network; the mapping relation information between the same global VLAN and the global Instance is configured; switching equipment between different MST domains is distinguished; and independently calculating a spanning tree for each global Instance without distinguishing whether the switching equipment is in the same MST domain. According to the scheme, the VLAN is divided into the global VLAN and the common VLAN, and the mapping relation between the global VLAN and the global Instance is established, so that a GSTI topology is independently calculated for each global Instance; when a plurality of links exist between MST domains, different data transmission topologies are generated for different global Instances by adjusting the global Instance bridge priority and port path overhead of each device, so that the load sharing of traffic between different MST domains is effectively realized.

Description

Technical Field

[0001] This invention relates to the field of traffic load sharing technology among MST domains, and in particular to a method, system and apparatus for achieving traffic load sharing among multiple MST domains. Background Technology

[0002] In a typical Layer 2 network, MSTP (Multiple Spanning Tree Protocol) is usually deployed to block certain ports on redundant links, forming multiple loop-free trees. This resolves the loop broadcast storm problem without affecting hardware link and device redundancy. MSTP can map one or more VLANs to different instances, and then calculate and maintain the spanning tree based on that instance. The spanning tree based on the instance is called MSTI (Multiple Spanning Tree Instance). Because the topology calculations for each instance are independent, different instances can obtain different topologies by blocking different ports.

[0003] MSTP can also divide a large switching network into multiple Spanning Tree Regions (MSTs). An MST can contain one or more switches. Switches belonging to different MSTs are distinguished by configuring different domain names, revision levels, or VLAN-Instance mappings. Switches belonging to the same MST must be configured with the same domain name, revision level, and VLAN-Instance mapping. Through MST region division, MSTP effectively reduces the complexity and difficulty of configuring and managing large switching networks, reduces the spanning tree size, simplifies calculations, and accelerates topology convergence.

[0004] In existing MSTP, only one Common Spanning Tree (CST) is calculated between each MST domain. This treats each MST domain as a node, and then uses STP (Spanning Tree Protocol) or RSTP (Rapid Spanning Tree Protocol) to calculate a single spanning tree. The CST calculation means that at most one link can be reserved for data transmission between adjacent MST domains, and the protocol blocks ports on other links to prevent loops. This means that even if multiple links exist between MST domains, they cannot be used simultaneously for load balancing. When data traffic between MST domains is high (e.g., in the same MSTP network, there are multiple multicast sources and receivers, and the multicast sources and receivers are not in the same MST domain), the links between MST domains become the bottleneck for the transmission performance of the entire Layer 2 switching network. Figure 1 The diagram shows a network topology with multiple MST regions (MST Region0-2). After calculating the CST, the blocked region edge ports cannot be used by any VLAN data traffic.

[0005] To address the aforementioned issues, patent application CN102497324B, entitled "A Method and Device for Data Transmission Between Different MST Domains," discloses a method where: a virtual proxy device is elected within each MST domain; two mapping relationships are configured on all devices: VLAN to private instances and VLAN to public instances; forwarding is performed within each MST based on the private instance topology; and forwarding is performed at the domain edge ports based on the public instance topology calculated by the virtual proxy device. While this can solve some traffic load balancing issues, it requires additional device attribute configuration, maintenance of additional information such as domain edge port mapping tables, modification and extension of existing BPDU message formats, and cumbersome operations such as additional protocol message interactions. Summary of the Invention

[0006] The purpose of this invention is to provide a method, system, and apparatus for traffic load sharing among multiple MST domains, so as to solve at least one of the above-mentioned technical problems existing in the prior art.

[0007] In a first aspect, to solve the above-mentioned technical problems, the present invention provides a method for implementing traffic load balancing among multiple MST domains, comprising the following steps: Step 1: In an MSTP (Multiple Spanning Tree Protocol) network, configure the same VLAN (Virtual Local Area Network) partitioning scheme for all switching devices in multiple MST domains to divide VLANs into global VLANs and ordinary VLANs; and configure the same mapping relationship information between global VLANs and global instances. Step 2: Based on the distinguishing condition information, distinguish the switching devices between different MST domains; Step 3: In an MSTP network, regardless of whether the switching devices are in the same MST domain, a separate spanning tree, namely GSTI (Global Spanning Tree Instance), is calculated for each global instance to transmit global VLAN data traffic between MST domains. In this way, since the calculation of GSTI is independent of CST, the data traffic of global VLANs can be transmitted between MST domains and the traffic load can be shared based on different CST topologies; while the data traffic of ordinary VLANs is consistent with the existing MSTP, that is, it is transmitted based on different MSTI (Multiple Spanning Tree Instance) within each MST domain, and CST is used for transmission between MST domains.

[0008] In one feasible implementation, the distinguishing condition information includes any one of the following: domain name; MSTP revision level; Mapping relationship between ordinary VLANs and MSTI; In this way, devices in different MST domains can be effectively distinguished by different domain names, different MSTP revision levels, or different mapping relationships between ordinary VLANs and MSTI.

[0009] In one feasible implementation, the mapping relationship information and the distinguishing condition information are transmitted through the fields of the domain configuration information in the MST BPDU (Multiple Spanning Tree Bridge Protocol Data Unit) message, thereby eliminating the need for additional field expansion.

[0010] Secondly, based on the same inventive concept, this application also provides a system for traffic load sharing among multiple MST domains, including a data receiving module, a data processing module and a result generation module; The data receiving module is used to receive information about all switching devices in multiple MST domains of the MSTP network; The data processing module includes a configuration unit, a differentiation unit, and a GSTI unit; The configuration unit is used to configure the same VLAN partitioning scheme for all switching devices in multiple MST domains throughout the entire MSTP network, which is used to divide VLANs into global VLANs and ordinary VLANs; and to configure the same mapping relationship information between global VLANs and global instances. The differentiation unit is used to differentiate switching devices between different MST domains based on differentiation condition information; The GSTI unit is used to calculate a separate spanning tree for each global instance in the entire MSTP network, regardless of whether the switching devices are in the same MST domain, for global VLAN data traffic transmission between MST domains. The result generation module is used to send out the VLAN partitioning scheme, the mapping relationship information, and the spanning tree.

[0011] Thirdly, based on the same inventive concept, this application also provides an apparatus for implementing traffic load sharing among multiple MST domains, including a processor, a memory, and a bus. The memory stores instructions and data that can be read by the processor. The processor is used to call the instructions and data in the memory to execute the method for implementing traffic load sharing among multiple MST domains as described above. The bus connects the functional components for transmitting information.

[0012] By adopting the above technical solution, the present invention has the following beneficial effects: This invention provides a method, system, and apparatus for traffic load balancing across multiple MST domains. In an MSTP network containing multiple MST domains, VLANs are divided into global VLANs and ordinary VLANs, and a mapping relationship is established between the global VLANs and global instances. Thus, a separate GSTI topology is calculated for each global instance in the entire MSTP network. When there are multiple links between MST domains, different data transmission topologies are generated for different global instances by adjusting the bridge priority and port path cost of each device's global instance, thereby effectively achieving traffic load balancing between different MST domains. This solution requires no additional device attribute configuration, no maintenance of domain edge port mapping tables or other additional information, no modification or extension of the existing BPDU message format, and no additional protocol message interaction. It can reuse and be compatible with the existing MSTP protocol process to the greatest extent. This solution has good compatibility and strong scalability. When all VLANs are divided into ordinary VLANs, it can be networked with other devices in the existing MSTP network. Attached Figure Description

[0013] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram illustrating the message processing flow between multiple MST fields in the background technology. Figure 2 This is a flowchart of BPDU message processing provided in an embodiment of the present invention; Figure 3 The following are topology examples of CIST and GSTI provided in the embodiments of the present invention; wherein, a is the topology example of CIST with instance ID 0, b is the topology example of GSTI with instance ID 48, and c is the topology example of GSTI with instance ID 49. Figure 4 This is an example diagram of the transmission topology of ordinary VLAN data traffic in an MSTP network provided in an embodiment of the present invention; Figure 5 This is a system diagram for implementing traffic load sharing among multiple MST domains, provided as an embodiment of the present invention. Detailed Implementation

[0015] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0017] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0018] The present invention will be further explained below with reference to specific embodiments.

[0019] It should also be noted that the specific embodiments or implementation methods described below are a series of optimized settings listed by the present invention to further explain the specific content of the invention, and these settings can be combined or used in conjunction with each other.

[0020] Example 1: This embodiment provides a method for implementing traffic load balancing among multiple MST domains, including the following steps: Step 1: In the entire MSTP (Multiple Spanning Tree Protocol) network, configure the same VLAN (Virtual Local Area Network) partitioning scheme for all switching devices in multiple MST domains to divide VLANs into global VLANs and ordinary VLANs; and configure the same mapping relationship information between global VLANs and global instances. Step 2: Based on the distinguishing condition information, distinguish the switching devices between different MST domains; Step 3: In the entire MSTP network, regardless of whether the switching devices are in the same MST domain, calculate a separate spanning tree for each global instance, namely GSTI (Global Spanning Tree Instance), which is used for global VLAN data traffic transmission between MST domains; In this way, since the calculation of GSTI is independent of CST, the data traffic of global VLANs can be transmitted between MST domains and the traffic load can be shared based on different CST topologies; while the data traffic of ordinary VLANs is consistent with the existing MSTP, that is, it is transmitted based on different MSTI (Multiple Spanning Tree Instance) within each MST domain, and CST is used for transmission between MST domains.

[0021] Furthermore, the distinguishing condition information includes any one of the following: domain name; MSTP revision level; Mapping relationship between ordinary VLANs and MSTI; In this way, by using different domain names, different MSTP revision levels, or different mapping relationships between ordinary VLANs and MSTI, switching devices in different MST domains can be effectively distinguished.

[0022] Furthermore, the mapping relationship information and the distinguishing condition information are transmitted through the fields of the domain configuration information in the MST BPDU (Multiple Spanning Tree Bridge Protocol DataUnit) message, thus eliminating the need for additional field expansion.

[0023] Furthermore, the specific VLAN division can be shown in Table 1:

[0024] Each global VLAN should have at least one corresponding global instance. Generally, the first configured global instance is used as the default global instance, and all unassigned global VLANs will be mapped to the default global instance.

[0025] It is important to note that a global instance that is mapped to a global VLAN cannot be mapped to a regular VLAN. That is, a global VLAN can only be mapped to a global instance, and a regular VLAN can only be mapped to a regular instance. Neither a global VLAN nor a regular VLAN can be mapped to a single instance, but multiple global VLANs can be mapped to the same global instance. The mapping relationship between regular VLANs and regular instances remains consistent with the existing MSTP implementation and will not be elaborated further.

[0026] Furthermore, the mapping relationship between VLANs and instances is shown in Table 2;

[0027] After completing the VLAN segmentation and VLAN-Instance mapping configuration, proceed to configure the bridge priority (the high 2 bytes of the bridge ID, used for root bridge election) corresponding to the global instance on the designated switching device, and configure the port path cost (one of the port attributes, used for root path cost calculation) corresponding to different global instances on the switching device ports. This configuration process is consistent with the current MSTP. At this time, each global instance will calculate its own GSTI through BPDU interaction throughout the entire MSTP network. The calculation of the GSTI corresponding to each global instance is independent of each other and does not affect each other.

[0028] It should be noted that the BPDU message format in the MSTP network after the above configuration is consistent with the existing MSTP implementation. The data fields related to GSTI follow the MSTI data format and are also part of the MST extension content in the BPDU message. That is, the BPDU message does not distinguish between MSTI and GSTI.

[0029] Furthermore, the specific methods for distinguishing between the processing of GSTI data in BPDU messages by the switching equipment and the processing of MSTI data by the current MSTP implementation include: Step a1: If the Instance ID (instance number) of a certain MSTI-related field (multiple fields may exist) in the MST extended data of the received BPDU message has a mapping relationship with the global VLAN configured on the current device, then it is determined to be GSTI data; Step a2: Whether the GSTI data is received from the Region Boundary Port or the Internal Port, GSTI calculation is performed. The specific method for GSTI calculation is the same as the algorithm for CIST (Common and Internal Spanning Tree, which is a single spanning tree that connects all switching devices in a switching network and is calculated by the STP or RSTP protocol) in the existing MSTP implementation, and will not be described in detail here. Step a3: Through interactive BPDU messages, for each global instance, a unique root bridge is elected in the entire MSTP network. The election method is consistent with the election of the overall root (the root bridge of CIST). Step a4: After completing the election of each GSTI root bridge, a root port is elected on all non-root bridge switching devices in the entire MSTP network, and a designated port is elected for each network segment. The election method is consistent with the election of root port and designated port in CIST. Step a5: After each GSTI completes the above election, it blocks other ports. The port status of other ports (the type of port status is defined in the MSTP protocol) is the same as that of the non-designated ports in CIST. The other ports refer to the remaining ports on each switching device other than the root port and the designated port. It should be noted that for domain edge ports, the port roles in each global instance will be displayed in GSTI, not in CST. That is, the port roles in GSTI will not have Master and Alternate roles. Step a6, GSTI calculation (i.e., the election process in steps a3-a5, obtaining the corresponding port status based on port role), obtains the port status of the switching devices under each global instance, and sends it to the hardware for execution along with the results of CIST and MSTI calculations. When a switching device port receives data traffic within the global VLAN, it determines whether to forward the traffic based on the port status of the corresponding global instance: if the port status of the root port and the designated port is forwarding, the data traffic of that global VLAN is forwarded; if the port status of other ports is discarding, the data traffic of that global VLAN is discarded. The above distinction process is as follows: Figure 2 The left half of the figure is shown, while the right half of the figure shows the processing method for ordinary MSTI data, which is consistent with the existing MSTP protocol and will not be repeated here.

[0030] In this way, based on the processing of the GSTI-related data mentioned above, the calculation of the GSTI topology in the entire MSTP network will be completely independent of the calculation of the CIST topology, and will not affect the calculation of the MSTI topology within each MST domain. Thus, when there are multiple paths between MST domains, the data traffic of the GSTI-corresponding VLAN can use a different path than CIST, thereby achieving traffic load sharing among multiple MST domains.

[0031] by Figure 1 Taking the MSTP network shown as an example, using the VLAN division shown in Table 1 and the mapping relationship between VLANs and Instances shown in Table 2, by adjusting the Instance priority and port path cost of each switching device, the following can be obtained: Figure 3 The CIST and each GSTI topology are shown; where, Figure a is an example of the CIST topology with instance ID 0, Figure b is an example of the GSTI topology with instance ID 48, and Figure c is an example of the GSTI topology with instance ID 49.

[0032] For data traffic within a global VLAN, it will be transmitted along the corresponding GSTI throughout the entire MSTP network; for data traffic within a regular VLAN, it will be transmitted along the CST between multiple MST domains; within an MST domain, data traffic of a regular VLAN will be transmitted along the corresponding MSTI.

[0033] Taking VLAN ID=10 as an example, in an MSTP network, all switching devices classify it as a regular VLAN. Therefore, traffic within VLAN 10 is transmitted along the CST between multiple MST domains. An example of the MSTI topology in MST Region 1 / 2, and the topology of how VLAN 10 data traffic is transmitted throughout the entire MSTP network, is shown below. Figure 4 As shown: In MST Region0, VLAN10 is mapped to Instance0, i.e., it is propagated along the IST (Internal Spanning Tree); in MST Region1 / 2, VLAN10 is mapped to Instance1 (i.e., ... Figure 4 (The left / right image in the lower middle section), that is, along the corresponding MSTI.

[0034] Example 2: like Figure 5 As shown, this embodiment provides a system for traffic load balancing among multiple MST domains, including a data receiving module, a data processing module, and a result generation module; The data receiving module is used to receive information about all switching devices in multiple MST domains of the MSTP network; The data processing module includes a configuration unit, a differentiation unit, and a GSTI unit; The configuration unit is used to configure the same VLAN partitioning scheme for all switching devices in multiple MST domains throughout the entire MSTP network, which is used to divide VLANs into global VLANs and ordinary VLANs; and to configure the same mapping relationship information between global VLANs and global instances. The differentiation unit is used to differentiate switching devices between different MST domains based on differentiation condition information; The GSTI unit is used to calculate a separate spanning tree for each global instance in the entire MSTP network, regardless of whether the switching devices are in the same MST domain, for global VLAN data traffic transmission between MST domains. The result generation module is used to send out the VLAN partitioning scheme, the mapping relationship information, and the spanning tree.

[0035] Example 3: This embodiment provides an apparatus for implementing traffic load balancing among multiple MST domains, including a processor, a memory, and a bus. The memory stores instructions and data that can be read by the processor. The processor is used to call the instructions and data in the memory to execute the method for implementing traffic load balancing among multiple MST domains as described above. The bus connects the functional components for transmitting information.

[0036] In another implementation, this solution can be achieved through an integrated device, which may include corresponding modules that perform one or more steps in the various embodiments described above. A module may be one or more hardware modules specifically configured to perform the corresponding step, or implemented by a processor configured to perform the corresponding step, or stored in a computer-readable medium for implementation by a processor, or implemented through some combination thereof.

[0037] The processor executes the various methods and processes described above. For example, the method implementations in this scheme can be implemented as software programs tangibly contained in a machine-readable medium, such as memory. In some implementations, part or all of the software program can be loaded and / or installed via memory and / or a communication interface. When the software program is loaded into memory and executed by the processor, one or more steps of the methods described above can be performed. Alternatively, in other implementations, the processor can be configured to execute one of the methods described above by any other suitable means (e.g., by means of firmware).

[0038] This device can be implemented using a bus architecture. A bus architecture can include any number of interconnect buses and bridges, depending on the specific application of the hardware and overall design constraints. The bus connects various circuits, including one or more processors, memory, and / or hardware modules. The bus can also connect various other circuits such as peripherals, voltage regulators, power management circuitry, external antennas, etc.

[0039] Buses can be Industry Standard Architecture (ISA) buses, Peripheral Component Interconnect (PCI) buses, or Extended Industry Standard Component (EISA) buses, etc. Buses can be divided into address buses, data buses, control buses, etc.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for implementing traffic load balancing across multiple MST domains, characterized in that, include: Step 1: In an MSTP network, configure the same VLAN partitioning scheme for all switching devices in multiple MST domains to divide VLANs into global VLANs and ordinary VLANs; and configure the same mapping relationship information between global VLANs and global instances. Step 2: Based on the distinguishing condition information, distinguish the switching devices between different MST domains; Step 3: In an MSTP network, regardless of whether the switching devices are in the same MST domain, calculate a separate spanning tree (GSTI) for each global instance to transmit global VLAN data traffic between MST domains.

2. The method according to claim 1, characterized in that, The distinguishing criteria information includes any one of the following: domain name; MSTP revision level; The mapping relationship between ordinary VLANs and MSTI.

3. The method according to claim 1, characterized in that, The mapping relationship information and the distinguishing condition information are transmitted through the fields of the domain configuration information in the MST BPDU message.

4. The method according to claim 1, characterized in that, A global VLAN can only be mapped to a global instance, and a regular VLAN can only be mapped to a regular instance. Both global VLANs and regular VLANs can only be mapped to one instance, but multiple global VLANs can be mapped to the same global instance.

5. The method according to claim 3, characterized in that, The MST BPDU message does not distinguish between MSTI and GSTI.

6. The method according to claim 5, characterized in that, The specific methods for distinguishing between the processing of GSTI data in BPDU messages by switching equipment and the processing of MSTI data by the current MSTP implementation include: Step a1: If the Instance ID of a certain MSTI-related field in the MST extended data of the received BPDU message has a mapping relationship with the global VLAN configured in the current device, then it is determined to be GSTI data. Step a2: GSTI calculation is performed on both the GSTI data received by the domain edge port and the GSTI data received by the domain internal port. Step a3: Through interactive BPDU messages, a unique root bridge is elected in the entire MSTP network for each global instance. The election method is the same as the root bridge election in CIST. Step a4: After completing the election of each GSTI root bridge, a root port is elected on all non-root bridge switching devices in the entire MSTP network, and a designated port is elected for each network segment. The election method is the same as the election of root port and designated port in CIST. Step a5: After each GSTI completes the above election, it blocks other ports. The port status of other ports is the same as that of the non-designated ports in CIST. The other ports refer to the remaining ports on each switching device other than the root port and the designated port. Step a6: GSTI calculates the port status of the switching devices under each global instance and sends it to the hardware for execution along with the results calculated by CIST and MSTI. When a switching device port receives data traffic from within the global VLAN, the port status of the switching device is calculated based on the corresponding global instance to determine whether to forward the data.

7. The method according to claim 6, characterized in that, For domain edge ports, they are displayed as port roles in each global instance in GSTI, but not as port roles in CST.

8. The method according to claim 6, characterized in that, In step a2, the GSTI calculation method is the CIST algorithm in the MSTP implementation.

9. A system for implementing traffic load balancing across multiple MST domains, characterized in that, It includes a data receiving module, a data processing module, and a result generation module; The data receiving module is used to receive information about all switching devices in multiple MST domains of the MSTP network; The data processing module includes a configuration unit, a differentiation unit, and a GSTI unit; The configuration unit is used to configure the same VLAN partitioning scheme for all switching devices in multiple MST domains throughout the entire MSTP network, which is used to divide VLANs into global VLANs and ordinary VLANs; and to configure the same mapping relationship information between global VLANs and global instances. The differentiation unit is used to differentiate switching devices between different MST domains based on differentiation condition information; The GSTI unit is used to calculate a separate spanning tree for each global instance in the entire MSTP network, regardless of whether the switching devices are in the same MST domain, for global VLAN data traffic transmission between MST domains. The result generation module is used to send out the VLAN partitioning scheme, the mapping relationship information, and the spanning tree.

10. An apparatus for implementing traffic load balancing across multiple MST domains, characterized in that, It includes a processor, a memory, and a bus. The memory stores instructions and data read by the processor. The processor is used to call the instructions and data in the memory to execute the method as described in any one of claims 1-8. The bus connects the functional components for transmitting information.

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