CN100452683C - Intelligent wavelength routing optical network node structure supporting link management protocol - Google Patents

Abstract

The present invention relates to an intelligent wavelength routing optical network node structure supporting a link management protocol. A transferring and coupling exchange structure is added on the existing single optical exchanger; an input part in the transferring and coupling exchange structure is composed of a plurality of 1*2 path splitters, optical door switches with the same quantity, a star coupler and a receiver; an output part is composed of a transmitter, a plurality of 1*2 optical switches, an optical door switch and a plurality of 2*1 couplers. A universal multi-mark exchange control plane software module controls and sends message formats according to data packet formats and processing mechanisms defined by the link management protocol LMP; the transferring and coupling exchange structure ensures that data emitted by the control plane software module can be transferred to other nodes by any output optical fiber on nodes. The present invention can support the automatic verification of adjacent nodes, detect the optical fiber connection relation of two adjacent nodes, and realize the automatic detection of the corresponding relation of all ports of the nodes by a channel associated signaling technology and the transferring coupling structure.

Description

Intelligent wavelength routing optical network node device supporting link management protocol

technical field

The invention relates to an intelligent wavelength routing optical network node device supporting a link management protocol, which is an intelligent optical network node device composed of an optical transceiver, an optical coupler, an optical switch, an optical switching module, and node control software. The invention belongs to the field of photonic systems in the optical communication technology.

Background technique

With the development of society and the advancement of technology, the demand for emerging broadband data services such as broadband video, multimedia services, bandwidth on-demand distribution, and optical path automatic supply continues to grow. Using wavelength division multiplexing (WDM) technology can simultaneously transmit multiple high-speed signals on one optical fiber, which greatly improves the transmission capacity of the optical fiber. The all-optical network solution based on wavelength division multiplexing technology has good transparency, wavelength routing characteristics, compatibility and scalability, and can adapt to the bandwidth requirements of high-speed broadband services for a long time, becoming the next generation of high-speed or even ultra-high-speed The first choice for broadband network.

The International Telecommunication Union (ITU-T) and the International Engineering Task Force (IETF) and other organizations are working on automatic optical path provisioning and fast protection and recovery protocols for WDM optical networks. At present, ITU-T has accepted the Generalized Multiprotocol Label Switching Protocol (GMPLS) proposed by IETF as the automatic switching optical network (ASON) control plane standard implementation protocol, and realizes the release of routing information and provides the ability of automatic supply of optical paths in the control plane. Realizing the automatic supply of optical paths can reduce the operator's expenditure on configuration, deployment, maintenance, and training of intelligent optical networks, and make full use of the existing optical transmission network resources.

After installing the intelligent optical network node equipment, the installer must configure the corresponding relationship between the fiber ports of adjacent nodes in accordance with the provisions of the Link Management Protocol (LMP) to ensure that the correct connection relationship table is established at the local node, which can be configured manually or automatically accomplish. Due to the good transparency of the all-optical network, pure optical switching nodes will not modify or check the data signals transmitted in the optical channel, making it very difficult to automatically discover the corresponding relationship between ports, which can only be manually configured by installation and commissioning personnel . Due to the variety of actual conditions at the installation site, manual configuration not only increases the operator's equipment training, maintenance, and operating expenses, but also is prone to configuration errors, resulting in wrong configurations when the control plane establishes optical paths. The automatic configuration of the relationship has a very realistic demand, and the existing pure optical switching equipment cannot support the automatic discovery function of the corresponding relationship between the optical fiber ports between nodes.

Contents of the invention

The purpose of the present invention is to address the deficiencies in the prior art, to propose an intelligent wavelength routing optical network node device that supports the link management protocol, supports adjacent nodes to automatically verify and detect the optical fiber connection relationship between two adjacent nodes, and through the channel-associated signaling The technology and the transmission and coupling structure realize the automatic detection of the corresponding relationship of all ports of the node, which has the advantages of low cost and convenient application.

In order to achieve such purpose, the intelligent wavelength routing optical network node device supporting the link management protocol proposed by the present invention adds a delivery-and-coupling switch on the existing pure optical exchange matrix (PXC), and The link management protocol LMP is implemented on the all-optical switching node to automatically verify the port correspondence between adjacent nodes.

In the technical solution of the present invention, the transmission coupling switch is divided into two parts, the input part and the output part. The input part is composed of several 1×2 splitters, the same number of optical gate switches, a star coupler and receiver; the output part is composed of a 1510nm transmitter, several 1×2 optical switches, and an optical gate Switches and several 2×1 couplers. In the input part, each input fiber of the node is first divided into two paths through an optical splitter, one path is connected to the input port of the pure optical switch matrix, and the other path is connected to one end of an optical gate switch through an optical fiber. The other ends of all optical gate switches are connected to the input port of the same star coupler through optical fiber, and the output end of the star coupler passes through a 1510nm receiver and finally exchanges with the general multi-label control plane software module (abbreviated as the control plane software module ) connection; the output of the control plane software module is connected to the output part of the transmission coupling switch, connected to the input port of the 1×2 optical switch group through the transmitter, and one output port of each 1×2 optical switch in the 1×2 optical switch group And the output port of the pure optical switch matrix is connected with a 2×1 coupler through an optical fiber, and the other output port is connected with the input port of the next 1×2 optical switch, and the last 1×2 optical switch passes through an optical gate switch and a coupler connected. The output ports of different 2×1 couplers are all connected to different node output fibers.

Each optical fiber entering the node splits 10% of the optical signal through the optical splitter on the respective channel, and enters a star coupler through the optical gate switch to collect the optical signals from all incoming optical fibers. The optical door switch has a pair of input and output ports, which can control whether the optical signal input to the optical door switch is output from the output port, and can make the optical door switch in two states of on-circuit or off-circuit. Under normal working conditions, only one of these optical gate switches is in the on-circuit state, and the others are in the off-circuit state. The control plane software can control the input part of the transmission coupling switch to collect only any signal. The output port of the star coupler is connected with a 1510nm receiver to convert the optical signal into an electrical signal, and the data carried by it enters the control plane software module for processing. This working mechanism ensures that there is one and only one input fiber data to be processed.

The control plane software converts the data to be sent through the 1510nm transmitter into an optical signal, and enters the output part of the transmission coupling switch. The output part of the transmission coupling switch is composed of several groups of 1×2 optical switches and optical gate switches, among which the 1×2 optical switch has one input port and two output ports, which can switch the input optical signal to the two output ports as required anyone. In the transmission coupling switch, all 1×2 optical switches are connected to each other, that is, the input port of the first 1×2 optical switch is connected to the output port of the 1510nm transmitter, and one of its output ports is connected to the output port of the next 1×2 optical switch. The input port is connected, and the other output port is connected to the 2×1 coupler through optical fiber, and so on. Assuming that the node has n output fibers, corresponding to the first n-1 fibers, there is a 1×2 optical switch connected to it, and the other port of the n-1th optical switch is connected to the coupler through an optical gate switch . Therefore, there are n output optical fibers in this node device, the number of 1×2 optical switches is n-1, and there are n+1 optical gate switches, of which n are connected to the input optical fiber, and only one is connected to the output optical fiber. . The 1×2 optical switch has two working states: straight-through and crossover. If the optical switch is in the straight-through state, it can transmit the input optical signal to the input port of the next adjacent 1×2 optical switch in the transmission coupling switch; If it is a cross state, the input optical signal will reach the optical gate switch corresponding to this optical switch. The purpose of the design of the transmission coupling switch is to ensure that the data sent by the control plane software module can be transmitted to other nodes by selecting any output fiber on the node.

The control plane software module and the sent message format follow the data packet format and processing mechanism defined by the Link Management Protocol (LMP) formulated by the IETF organization. When there is no need to use the transmission coupling switch, all the optical gate switches can be set to the off state, and all the 1×2 optical switches can be set to the through state.

The intelligent wavelength routing optical network node device supporting the link management protocol of the present invention can support the adjacent nodes to automatically verify and detect the optical fiber connection relationship between two adjacent nodes, and realize the correspondence of all ports of the nodes through the channel-associated signaling technology and the transmission and coupling structure Automatic detection of relationships. The invention has a simple structure, and all related functions can be realized by using cheap optical devices, which effectively reduces the cost of realizing the function of automatically discovering the corresponding relationship between ports, and has high working stability and reliability. It can be applied to larger-scale nodes only by increasing the number of 1×2 optical switches and optical gate switches and the number of cascaded star couplers, and the structure has good scalability.

Description of drawings

FIG. 1 is a schematic structural diagram of an intelligent wavelength routing optical network node device supporting a link management protocol of the present invention.

As shown in Figure 1, the node device of the present invention adds a transmission coupling switch on the basis of the PXC pure optical switching matrix as the processing core, which is used to select the optical fiber port for receiving or sending, and realizes automatic testing and verification of port correspondence.

FIG. 2 is an example of realizing the automatic discovery and verification of port correspondence between two adjacent switching nodes A and B in the present invention.

As shown in Fig. 2, the present invention coordinates nodes A and B to select a port pair to be detected by configuring the transmission coupling switches of the receiver and the sender, and performs automatic verification and testing.

Detailed ways

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

The structure of the intelligent wavelength routing optical network node device supporting the link management protocol of the present invention is shown in FIG. 1 .

The node device shown in Figure 1 is composed of two parts: a pure optical switching matrix and a transmission coupling switch. The optical fiber signal entering the node will be divided into two paths, one into the pure optical switching matrix, the other into the transmission coupling switch; the optical signal output by the transmission coupling switch and the output signal of the pure optical switching matrix enter the output fiber of the node through the coupler, as the node output signal. The transmission coupling switch is divided into two parts, input and output. The input part is composed of several 1×2 splitters, the same number of optical gate switches, a star coupler and receiver; the output part is composed of a 1510nm transmitter, several 1×2 optical switches, and an optical gate Switches and several 2×1 couplers. In the input part, each input optical fiber of the node is first divided into two paths through an optical splitter, one path is connected to the input port of a pure optical switch, and the other path is connected to one end of an optical gate switch through an optical fiber. The other ends of all optical gate switches are connected to the input port of the same star coupler through optical fiber, and the output end of the star coupler passes through a 1510nm receiver and finally exchanges with the general multi-label control plane software module (abbreviated as the control plane software module ) connection; the other part is that the transmitter is connected to the input port of the 1×2 optical switch group, and an output port of each 1×2 optical switch in the 1×2 optical switch group is connected to an output port of the pure optical switch matrix with a 2 The ×1 coupler is connected through an optical fiber, and its other output port is connected to the input port of the next 1×2 optical switch, and the last 1×2 optical switch is connected to a coupler through an optical gate switch. The output ports of different 2×1 couplers are all connected to different node output fibers.

Each input fiber of the node in Figure 1 passes through a 10/90 splitter to split 10% of the optical signal as the input signal of the transmission coupling switch, and they enter the star coupler through their respective optical gate switches. When the state of the optical gate switch on one input fiber is in the on state, the state of the light gate switch on the other fibers must be set to the off state, which ensures that only one input fiber signal can enter the star coupler at a certain time . The control plane software module can arbitrarily select one signal from all the signals from the input optical fiber, and after the 1510nm receiver converts it into an electrical signal, the information it carries is sent to the control plane software module for processing. The message sent by the software module of the control plane is sent to the output part of the transmission coupling switch, converted into a 1510nm optical signal by the transmitter, configured with cascaded 1×2 optical switch group and optical gate switch, and then transmitted through the coupler into the output optical fiber. The optical signal output from the transmitter can be switched to any output fiber. Whether the output part of the transmission coupling switch can work normally depends on the mutual cooperation of the 1×2 optical switch group, that is, at most one optical switch in the optical switch group in the transmission coupling switch can be in the cross state, so that the optical transmitter output The signal is switched to any output fiber of the node. When all 1×2 optical switches are in the through mode, the optical gate switch in the output part of the transmission coupling switch must be set to the through state. When there is no need to use the transmission coupling switch, all the optical gate switches can be set to the off state, and all the 1×2 optical switches can be set to the through state.

Fig. 2 is an implementation example of the present invention applied to an actual intelligent optical network.

In Figure 2, nodes A and B are adjacent nodes, and the output optical fiber of node A is connected to the input optical fiber of node B one by one. The automatic verification and verification of the corresponding relationship between the ports of node A and node B can be realized through the transmission coupling switch shown in Figure 1. test. Before installing and configuring the GMPLS control plane, it is necessary to determine the fiber connection mode between A and B. The <port p, port q> two-tuple can describe the port connection relationship between A and B. All ports connecting A and B The tuples form the port connection relationship table on A and B. The detailed working process of nodes A and B using the present invention is shown in FIG. 2 . The curve across nodes A and B in the figure shows how to route the signaling message used to verify link connectivity in the LMP protocol. Here, the optical signal on the link AB is transmitted from A to B, that is, to detect and verify the corresponding relationship between the outgoing fiber port on node A and the incoming fiber port on B. The control plane software module of node A configures a group of 1×2 optical switches and optical gate switches on its transmission coupling switch to the crossover and channel states respectively, and the optical signals reach node B through their corresponding output fibers, and the control plane of node B The software module will sequentially select one of the input fibers of all unverified port correspondences on the node. If a certain input fiber is selected, the control module software receives a signaling message from node A, which means that the port q where the input fiber is located corresponds to the port p selected by node A, and the binary group of the corresponding port <p , q> is saved in the port correspondence table of nodes A and B. When the GMPLS control module transmits signaling messages, it needs to control the transmitter on node A, the corresponding 1×2 optical switch and optical gate switch, and select the specified output fiber coupling to transmit signaling messages; node B controls the optical gate switch and receiver Module, select the input fiber that needs to be specified. After traversing all the output fibers on node A in this way, all port connection correspondences will be found. When all output fibers connected to node B on node A have been detected and verified, LMP will provide a complete port correspondence table for other operations on the control plane.

Claims (3)

1. An intelligent wavelength routing optical network node device supporting a link management protocol, characterized in that a transmission coupling switch is added to the existing pure optical switching matrix, and the automatic verification phase of the link management protocol is realized on the all-optical switching node The port correspondence between adjacent nodes, the transmission coupling switch is divided into two parts: input and output, in which the input part is composed of several 1×2 splitters, the same number of optical gate switches, a star coupler and receivers, and the output The part is composed of a 1510nm transmitter, several 1×2 optical switches, an optical gate switch and several 2×1 couplers. In the input part, each input fiber of the node is divided into two paths through an optical splitter. , one path is connected to the input port of the pure optical switch matrix, the other path is connected to one end of an optical gate switch through optical fiber, and the other ends of all optical gate switches are connected to the input port of the same star coupler through optical fiber, star coupling The output end of the device is connected to the general multi-label switching control plane software module through the 1510nm receiver; the output of the control plane software module is connected to the output part of the transmission coupling switch, and is connected to the input port of the 1×2 optical switch group through the transmitter, 1×2 One output port of each 1×2 optical switch in the optical switch group and the output port of the pure optical switch matrix are connected to a 2×1 coupler through an optical fiber, and the other output port is connected to the input of the next 1×2 optical switch port, the last 1×2 optical switch is connected to a coupler through an optical gate switch, the output ports of different 2×1 couplers are connected to different node output fibers, and each fiber entering the node passes through its own channel The optical splitter divides 10% of the optical signal, and enters a star coupler through the optical gate switch, and the control plane software controls the transmission coupling switch input part to collect only any signal, and transmits the data to be sent through 1510nm The machine converts the electrical signal into an optical signal, and outputs it through the output part of the transmission coupling switch. 2. The intelligent wavelength routing optical network node device supporting the link management protocol according to claim 1, characterized in that the message format controlled and sent by the general multi-label switching control plane software module is in accordance with the link management protocol LMP defined Packet format and processing mechanism. 3. The intelligent wavelength routing optical network node device supporting the link management protocol according to claim 1, characterized in that when the transmission coupling switch is not needed, all the optical gate switches in the transmission coupling switch are set to the disconnected state, and all 1×2 The optical switch is set to a straight-through state.

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