TW515169B - Automatically distributed network topology discovery method - Google Patents

Abstract

The invention relates to an automatically distributed network topology discovery method using tree structure to distribute detection message and determine required network topology based on the calculation of response message. The method includes that creates an initialization phase to create a leader node as root of tree message transmission structure, uses the tree message transmission structure to build up a data collect phase, making the leader node of the tree message transmission structure to obtain the response message of all other nodes, and determines a network topology in accordance with all response messages.

Description

rfii Xiu jl Buwu No. 90104820 Rev. V. Description of the invention (1) Background of the invention The present invention relates to a method for network topology discovery (netw rk topology discovery), and in particular to a decentralized network The topology is an automatically distributed network topology discovery method, which calculates a distributed response message to automatically detect a network topology. In the telecommunication network, the network is one of the important information for managing the telecommunications network. Taking a synchronous digital hierarchy network (Synchronous Digital Hierarchy: SDH) as an example, the

The SDH circuit has become the world standard for current long-range optical fiber communication, and it is also the backbone of the broadband ISDN. The SDH transmission network consists of a digital crossconnect device, an add / drop muitiplexer, and a high-capacity fiber-optic transmission device. Facing this complex transmission network, network management is very important. "Bajiu

Lujia Telecom's network needs are different from the environment. The SDH transmission wheel network is "tree connection ion" and "ring connectlon" in the figure, where the tree; ί: t; ΐ The point-to-point connection (dot _ect 10n) in Fig. 1b and the star connection in Fig. 1b. When an SDH network failure is completed, the network administrator must configure the network to enable a "network eleinent". Project j based on the system architecture (network topology), for each network

515169

Make. With the increase of the network hierarchy or the increase of new network components in the system, network setting and management will become more and more difficult. Therefore, an automatic detection network topology (automatic t0p0gy, discovery) method for simplifying the setting of fish management has been proposed. The currently proposed automatic detection network topology (aut〇matic topology diSC〇very) method is based on Transmission Control Protocol / internet _

Protocol: TCP / IP) network, or use Asynchronous Transfer Mode network to obtain ATM network topology information by using internal specific transmission channels. Both must concentrate all information on a specific node (specific ode) for calculation in order to obtain network topology information. 'This method will waste a great amount of network bandwidth. In view of this ,, An object of the present invention is to provide a distributed network topology automatic detection method, which determines the overall topology of the network by performing a small amount of calculation on each network node dispersed in the network. In this way, network resources (bandwidth) caused by centralized computing can be saved. The present invention is a decentralized network topology automatic detection method, which is decentralized: The design of the distributed computing can avoid the bandwidth waste caused by traditional centralized computing. The method includes the following steps: establishing an initial phase to generate a tree-like message passing structure with a leading node (16 to ^ node) as the root; using the tree-like message passing structure to Establish a data collection phase, so that the leading nodes of the tree-like messaging architecture (eader node) can obtain

515169 M: 203, ′: Case No. 90104820 V. Description of the invention (3) and the response information of all other nodes is determined according to all the response information Network topology. The detailed description of the better implementation example: Because an SDH network covers a large range, when managing an SD {I network, the entire SDH network is generally planned into several sub-networks (Suj-ndW0rk) for management settings. work. Subnet

The Sub-network Management System will fetch !! " Zi Zhoulu's network management information through the Gateway Network Element (GNE). The gateway network component provides a network management communication interface, which is a bridge for information communication between the subnet management system and the subnet. Refer to Figure 3, which is a system architecture diagram of the present invention. In Figure 3, there are two—ring subnetworks R1, R2, and three tree subnetworks TI, T2. As shown in Fig. 3, the subnet ruler 1 is composed of nodes ADM1, ADM2, ADM3, and 4 'and the subnet R2 is composed of nodes (nocje) ADM3, ADM5, ADM6, and ADRF. The subnetworks R1 and R2 are interconnected by the node ADM3. The subnet ^ is composed of nodes ADM5, 丨 and, where the subnet η is

= ^ DM5 is interconnected with the subnet ^. The subnet 2 is composed of nodes DM7 and T Μ 3, which is taken by Ganshan. The subnet T2 is interconnected by the node ADM7 and the subnet R2. The method of the present invention can be clearly described. The network in Figure 3 is shown in a topological form. In Figure 4, each circle represents: fixed network nodes (each ADM and each TM), each node is linked to form a network

Road Top. "As usual" --- As shown in the figure, the node where a network gateway network element is located, we call it a collar (here, node 0) and P / (Leader Node), the angle of the leader node information pool ρ The initiator and example of the dynamic network topology detection are detailed in the role of ^. The method of automatic detection of the network topology of the present invention will be based on this [conceptual description] We assume that the network in the network: the ancient (Bi-dirert · 1.) Some links are two-way to pass through this One to make ί = means that two nodes at both ends of a link can have one link then = :: Interest transfer: If the two nodes are > and Ichiro points are neighbors to each other (neighbor). There will be three variables on the node: pointer, type, and graph 0p: 2. Right: For the entire network, we will use the leading node, such as 4 =, point 0 'for s (Root) to build a tree form. Each node The Pointer variable value in it will point to the parent node adjacent to it, and the type variable value is used to indicate that the node belongs to the connection. That is, in a round point 'if the value of type is Tree, the node is located in a tree (Tree), if the value of type is Ring, it means that the node is located on a certain ring (Ringj. Also, the topology variable is a data structure that records the network of the sub-tree with the node as the root. Lu Tuopu. Later, we will further introduce the data structure representation of topology variables If each node can determine its type value by itself, the message can be greatly aggregated into a simple message, which can greatly reduce the transmission of the message. The feature of the present invention is that each node has its own value of typ ^ The method of the present invention includes the following steps: establishing an Initialization Phase and establishing a Data Collection Phase.

Collect Phase), as follows: Establish the initial phase: The initial phase is initiated by the leader node. First, the leader node sends a message to all its neighbors (such as the node in Figure 4) *. When a node receives the INIT message from the leader node, the node will set its own pomter to The parent node (parent node) then sends the INIT message from the leader node to the child nodes connected to it. That is, the 领导] ^ message from the leader node is passed in order (except that it has been sent out). INIT message outside the node) to the end. Here, we assume that each node will only send a j N 丨 τ message to the same link. When a node receives the IN 丨 T from the same node for the second time When the message is transmitted, the INIT message will be discarded. In this way, the path formed by the 丨 N 丨 τ message transmission can be expressed as a tree-like distribution with the root node as the root. RET two kinds of messages to determine the topology of the network system. The decision logic (decision algorithm) is described as follows: (1) When a node has only one neighbor and receives j N 丨 τ messages, it means when this condition is established A node is located at the leaf end of a tree (Leaf Node), then the node sets its value of pointe; r, and sets the value of type to Tree. Its variable topology records the root with: = dagger node Sub-tree structure (currently this sub-tree contains only one node). ^ Finally, this node sends a RET message to the parent # point pointed to by the pointer, which contains the type and topology values. Section

515169 r -------.

Oi has been on the record for many years 竑 90104820_ ar τ π ζ ·. · ------- ^-1 Correction-Explain that MD! An INIT message indicates that the node is in a ring (R ing). At this time, the node treats the IN 丨 T message sent from node j as a RET message ', and the values of the variable type and topology carried in the RET message are Ring and node j, respectively. When the node receives the RET message from all the neighbors (except the first node that sent IN 丨 T message), it first makes the following two judgments and processes: (a) The value of type in all RET messages is The number of Ring messages is even 'then the node sets its type to Tree and updates its value of t〇p〇l〇gy according to the topology information received in RET, so the topology records the subtree Topology. (b) In all RET messages, the type is Ring and the number of messages is an odd number. Then the node sets its tyPe to Ring and updates its t〇p〇1 according to the received topology information in RET. The value of gy, so t〇p〇l〇gy records the topology of the subtree. Finally, this node sends a RET message to the node pointed to by pointa, which contains the values of t y p e and topology. (3) If the conditions of Tian (1) and (2) are not satisfied, and the node receives the RET message from all neighbors (except the node that sent the INIT message), the node makes the following two judgments and Processing: U) In all RET messages, the type is Ring and the number of messages is even. Then the node sets its type to Tree and updates its t〇p〇1 according to the received topology information in RET. 〇gy, so topology records the topology of the subtree.

515169 The day of Xiuqiao East: <, No. 90104820, said to amend 1 ^ ^ I Έ. ≫ ^ 3ΜΜ ^ Τ ^ (b) in all RET messages, the number of Ring values is odd, then the node sets it The value of type is Ring and its value is updated according to the topology information received in RET, so the topology records the topology of the subtree. Finally, this node sends a RET message to the section indicated by pointe: r, which contains the values of type and top〇gy. Finally, after the leader node also completes the above steps, the leader node topology contains the topology of all networks. The decentralized network topology automatic detection method of the present invention will be expressed using the above message-driven algorithm. The detailed description is as follows: rn Μ ΓVariable): There are three variables on each node: (1) pointer: this one variable The J value of 扣 is deducted to the parent node adjacent to it. (2) type: The possible value of this variable is the Tree formula ρ ·. The value indicates that the node is located on a tree or a ring. g (3) topology: a data structure, a network topology of a widely rooted sub-tree. σ and the message point (Message): (1) I N I T: Scatter from the tree root to the leaf nodes of the tree. (2) RET: From the leaf nodes of the tree to the root of the tree. The message carries the type of the sender and t0p0gyy β T (3) message conversion: when the A node goes to the β node% + value. After the message, if Α also receives INI from B and sends out an ΙΝΤ message from ΙΝΤ B, it considers a heart ’, then Α will point 515169

The values of the type and t〇p〇1〇gy that RET Xunxin brings are called j1] (Decision Algorithm). We describe our algorithm in a message-driven manner. Except for the leading node, which is automatically executed in the initial stage, other nodes will execute the corresponding program fragments when they receive any message. When the leader node starts to detect the network topology, it will perform the following procedure. Program:

Initiate: B

The leader node i

For each neighbor j 〇f n〇de i, send INIT to j.} When any node receives a message, it will execute the following processing procedures.

When node i receives a message: if node i receives INIT from node j {pointer: = j; if node i has only one neighbor j {type: = Tree; update topology according to the values of

Page 11 515169 Case No. 90104820 Revised — V. Description of Invention (9) topologies in RETs; send RET (type, topology) to node j.} Else

For each neighbor k (k 1 j) of node i, send INIT to node k.} Else if node i receives INIT from node k, but it has received INIT from node j {node i translates INIT from node k as RETCRing, k ). if node i does not send INIT to node k node i sends INIT to node k.} if node i receives all RET (type, topology) from all neighbors j (j 1 pointer) if number of RET messages containing type equal to Ring is even type: = Tree else type Ring update topology; send RET (type, topology) to pointer.

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Modification [Embodiment] Referring to Fig. 5, it is an embodiment for executing the method of the present invention by using the above program. This embodiment is an initial stage established based on the network topology of FIG. 'As shown in Figure 5, node 0 is the leader node. In the initial stage, node 0 sends iNIT messages to its two neighbor nodes i and 2. After receiving the I N IT message, node 1 sends an I n IT message to node 3. After receiving the I N IT message, node 2 also sends an I n IT message to node 3. Assume that the I N IT message from node 1 arrives at node 3 first, then node 3 sends I N IT messages to nodes 2, 4, and 5. In this way, nodes 2 and 3 will receive I N ITT messages sent from each other, and they will convert this I N I T message into a ring representative symbol RET (Ring, α) (where α is the node that sent the INIT message). After receiving the I Ν Τ message, node 4 sends an I Ν Τ message to nodes 6, 7, and 8. Node 5 sends an I N ITT message to nodes 6 and 9 after receiving the I N ITT message. Assume that the I N ITT message of node 4 arrives at node 6 first, and then node 6 also sends the I NIT message to node 5. In this way, nodes 5 and 6 will receive the I Ν Τ message from each other, and they will also convert this ΙΝΤ message into the symbol RET (Ring, α) (α represents the node that sends the ΙΝ Τ message). Referring to Fig. 6, it is a data collection stage in Fig. 4. As shown in Figure 6, at this stage, nodes 2 and 6 send RET messages to their parent nodes, where the value of the variable type is Ring. Nodes 7, 8 and 9 are leaf nodes (child nodes). They will first send RET messages to their parent nodes, where the value of the variable type is Tree. After node 4 receives the RET messages from nodes 6, 7, and 8, the number of rings is odd because the RET message carried by the value of variable type is odd

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90104820 V. HWfFTH) — year, month, and day ___, so node 4 sets its variable type to Ring and continues to send RET message to node 3. After receiving the RET message from node 9, node 5 finds that the RET message with variable type Ring is also an odd number (note that the INIT message sent by node 6 is converted into a RET message with variable type Ring), so node 5 also converts it Set the type to Ring and send a RET message to node 3. Node 3 collects the information of nodes 2, 4 and 5 and sets its type to Ring (note that the INIT message sent by node 2 is converted to a RET message with ...) and sends a ret message to node 1. . After receiving the ret, node 1 also sets its type to Ring and sends a RET message to node 0. Finally, the section

Click 0 to receive an even number of RET messages of type Ring and thus obtain a complete network topology.

Referring to FIG. 7 to explain how the method of the present invention saves message transmission. In Figure 7, a branch from tree root (leaf node) to leaf node (node 0-node!-Node 3-node 4-node 8) is shown in Figures 5 and 6. As an example. As shown in Fig. 7, the amount of information transmitted by the method of the present invention in this branch is compared with the amount of information transmitted by the traditional centralized control calculation method. As a traditional centralized party, it is a shi (r001 centralized control and calculation, each node must be; its; = the message (the message shown by the dashed line in the figure below), so the closer to the "" point: Needed: The more messages you send. When we consider: The traditional way of intersections will be caused by the amount of information that is closer to the root node of the tree :: Too complicated to cause the root node of the tree to make a judgment error. Ϊ́ n Since: This issue: The use of decentralized computing can make each node only i [topological data structure representation] ¥ cause the problem of wrong judgment.

Year, month, day, day, day, day, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month, month This method uses a simple string to expand the network of two, two, and three paths, without the need to use any complex; = to construct a node and other methods. 2: 8, 8c and ⑺ graphs, Department of Topological Data-Structure #-^; (t: e :; irr: CrW 5 1 copy, then use R {x ,: if the _ node in the network is a ring To represent the section ... the child node is a Γ: × (Ί C ..) As shown in the graph of 8a, the ring can use R {cw ^. Therefore 'as shown, the tree can use T {r (x (a, h), 夂^ Mainly expressed. As shown in Figure 8b-a ring is hung on a tree, '7)} to represent. As shown in Figure 8c, T {r (R1 (z), down =., Can be the following way Representing: Also, as shown in FIG. 8d, ^ 'R3Ux, a, b, c}. The formula is expressed as follows: When the fruit tree is hung under the ring, the following R {r, T1 can be expressed. Although the present invention Tlib (x , Y)} · Used to limit the present invention, you: The Jiao Jia embodiment is disclosed as above, but it is not within the spirit and scope of the month, and the person with the dagger technique is deemed to be within the scope of this hair care The attached application II ^ ^ action and run Jin, so the definition of the Baoqiao patent of the present invention shall prevail. Page 15 515169 9Ϊ! .J il Right _ No. 90104j20 Modified diagram briefly explained A tree connection Figure lb shows a point-to-point connection (dot connection) Figure lc shows a star connection Figure 2 shows a ring connection Figure 3 shows a system architecture diagram of the present invention Figure 4 shows the system topology diagram of Figure 3 Figure 5 The figure is based on the initial stage of Figure 4. Figure 6 is based on the data collection stage of Figure 4. Figure 7 is a message comparison. Figure 8a is a data structure representation of a tree. Figure 8b is a circle of data Structure Representation Figure 8c is a tree and ring mixed data structure representation Figure 8d is another tree and ring mixed data structure representation. Explanation of the main component symbols:

Node TM, ADM Link STM-N, STM-N1, STM-N2, STM-N3, STM-N4 STM-N5, STM-N6, STM-N7, STM-N8 ring subnet R1, R2 Tree Subnet T1, T 2 Nodes ADM1, ADM2, ADM3, ADM4 ADM3, ADM5, ADM6, ADM7 Nodes 1, 2, 3, 4, 5, 6, 7, 8 1 N 1 T Tree root towards the leaves of the tree Nodes intersperse the leaf nodes of the RET tree toward the root of the tree

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Claims (1)

51-51-69 -———— ^, rpf, *: .- 他 .-, 91.U Shoulder '—r Case No. QmiUS9 (l _year month ______ 6. Application scope 1 · A decentralized network The Lutuopu automatic detection method includes the following steps: Establishing a first stage to generate a tree-like message transmission structure with a leader node as a root (! ^ 0〇1 :); using the tree-like message The transfer structure is used to establish a second stage, so that the leading node (1 eader η) of the tree-like message transfer structure obtains the response messages of all other nodes; and determines a network topology based on all the response messages. 2. The automatic detection method according to item 1 of the scope of patent application, wherein the leading node is a node where a gateway (g a t e w a y) network element is located. 3. The automatic detection method according to item 1 of the scope of patent application, wherein the network topology includes a tree type and a ring type. 4. The automatic detection method according to item 3 of the patent application scope, wherein the tree-like pattern further includes a point-to-point connection pattern and a star-shaped pattern. 5 · According to the automatic detection method of the first patent application scope, further determining a plurality of sub-trees in the generated tree-like message transmission structure, each tree having a plurality of nodes including one (rOOt) node, Each node has a pointer variable, a type variable, and a topology variable to control the transmission and response of the message. 6. Automatic test as described in item 5 of the scope of patent application. The value of the index (P0 = er) variable points to the adjacent variable; the upper node of the index indicates the location of the node where the message is transmitted. P7. If the automatic detection method of item 5 of the patent application scope, the node above it is the parent node of the node where the indicator variable is located. , The point the Page 17 Early Scope of Liuqin 8. Acknowledgement Youth Special — An automatic detection method of type = 5 in the type variable, among which the road is topological. The value indicating that the network topology variable that includes the node where the type variable is located is an automatic detection method around item 5, where the subtree (subtree) is based on the node where the topology variable is located. 1 '001 ^ 1. · If you apply for a wide-broadcast structure. Establishing the automatic detection method for the members of the second stage, in which recording and recording the network button of a subtree includes the following steps: determining and recording the embedded value to transmit and include; > The index variable U, as indicated, includes the recorded response message to the corresponding parent node. Decide and record the automatic detection method of the 10th item in the H range, in which 疋 亚 圮 records the network extension of the subtree: if the number of type changes received by the root node is an even number, then The surface dry spoon is not mounted ^ 11 ^) is tree-like; and if received by the root node; net; The table does not include the sub-tree network of this node. If you apply for the automatic detection method of item 10, = The step of recording the network topology of the sub-tree is to record the Park variable.