WO2018014274A1 - Method for establishing path, and node - Google Patents

Abstract

Disclosed are a method for establishing a path, and a node. The method comprises: a first node determining that a first LSP to be established comprises an FA link, an FA LSP corresponding to the FA link being a second LSP; the first node sending a path update message to at least one node on the second LSP, the path update message being used for indicating to adjust an attenuation value of a spectrum occupied by the first LSP in the FA link; and the first node sending a path establishment message to at least one node on the first LSP, the path establishment message being used for establishing the first LSP. The method for establishing a path and the node in the embodiments of the present invention can improve the utilization of spectrum resources.

Description

Method and node for establishing a path Technical field

The present invention relates to the field of communications and, more particularly, to a method and node for establishing a path.

Background technique

With the development of data plane technology, the Wavelength Division Multiplexing (WDM) transport network can only allocate/occupy fixed-spectrum resources in the early days. For example, it is fixed at 50 GHz or 100 GHz, and it can be allocated to the present. The sized spectrum resource, for example, can be allocated an integer multiple of the spectrum size of 12.5 GHz, such as 25 GHz, 200 GHz. The latter is known as the Flexible Grid WDM network.

The Generalized Multi-Protocol Label Switching (GMPLS) protocol family can also be used to implement intelligent control of flexible grid networks. Regardless of whether it is a fixed or flexible spectrum resource, adjacent spectrums will affect each other when transmitting services. Therefore, it is necessary to properly plan spectrum resources to ensure the impact of adjacent spectrum resources is minimized.

At present, the path establishment method of the flexi-grid network is implemented by using the Resource ReserVation Protocol-Traffic Engineering (RSVP-TE), which is: after the first node receives a single service request and calculates a path for it. The path establishment message is sent hop by hop to the last node; when the first node receives the reply message, the path establishment is completed, thereby being used for delivering the service data. The specific method of establishing such a path is to establish a path from the source node to the destination node through a single RSVP-TE process. In order to ensure that the impact between the paths is small, a part of the spectrum resources must be taken out as a protection band when the path is established, that is, the service data is not transmitted, and the spectrum resource utilization rate is not high.

Summary of the invention

The embodiments of the present invention provide a method and a node for establishing a path, which can improve spectrum resource utilization.

In a first aspect, a method of establishing a path is provided, including:

The first node determines that the first label switching path LSP to be established includes forwarding a neighboring FA link, and the FA LSP corresponding to the FA link is a second LSP;

The first node sends a path update message to at least one node on the second LSP, the path The update message is used to indicate that the attenuation value of the spectrum occupied by the first LSP in the FA link is adjusted;

The first node sends a path setup message to the at least one node on the first LSP, where the path setup message is used to establish the first LSP.

The method for establishing a path in the embodiment of the present invention uses the FA link to establish a path for a service request, so that when the service data is transmitted in the FA link, a small guard band may not be needed or set, thereby improving spectrum resource utilization.

In some possible implementations, a piece of spectrum resource may be represented in a manner of (n, m), where n represents the center frequency of the spectrum and m represents the width of the spectrum.

In some possible implementations, the first node receives a service request, where the service request is used to request to establish the first LSP;

The first node acquires the first LSP according to the service request.

In some possible implementation manners, after receiving the service request, the first node may calculate a path that can carry the service according to the service request, and obtain the first LSP.

In some possible implementation manners, after receiving the service request, the first node may also request other devices to calculate a path. For example, the other device may be a path calculation unit.

In some possible implementations, the first node receives a path setup message sent by the fourth node, where the fourth node is a previous hop node of the first node on the first LSP, and the path setup message is used by the first node. Establishing the first LSP, where the second path setup message carries the spectrum information occupied by the first LSP;

The first node acquires the first LSP according to the path setup message.

In some possible implementation manners, the first node determines that the first label switching path LSP to be established includes a forwarding neighbor FA link, including:

Determining, on the first LSP, that the link between the first node and the second node is the FA link, where the second node is the first node on the first LSP One hop node.

In some possible implementation manners, the first node determines that the first label switching path LSP to be established includes a forwarding neighbor FA link, and further includes:

The first node determines that the route of the first LSP includes the FA link, and the spectrum occupied by the first LSP is within the spectrum range of the FA link.

In some possible implementations, the first node sends a path update message to the at least one node on the second LSP, including:

The first node sends the path update message to the third node, where the third node is the first A node is a next hop node on the second LSP, and the path update message carries spectrum information occupied by the first LSP.

In some possible implementations, the first node sends a path update message to the at least one node on the second LSP, including:

The first node sends the path update message to each node except the first node on the second LSP, where the path update message carries the spectrum information occupied by the first LSP.

In some possible implementations, the first node sends a path setup message to the at least one node on the first LSP, including:

The first node sends the path setup message to the second node, where the first path setup message carries the spectrum information occupied by the first LSP.

In some possible implementations, the method further includes:

The first node receives a path update reply message in response to the path update message;

The first node receives a path setup reply message in response to the path setup message;

The first node determines, according to the path update reply message and the first path setup reply message, that the first LSP is established.

In some possible implementations, the method further includes:

The first node acquires the routing information of the first LSP and the occupied spectrum information according to the received service request or the path establishment message used to establish the first LSP.

In some possible implementations, the first node sends a path update message and a send path setup message, either in parallel or serially.

In some possible implementations, the method further includes:

When the link between the first node and the second node is not the FA link, the first node sends a path setup message to the second node, where the path setup message is used to establish the first LSP, the path The setup message carries the spectrum information occupied by the first LSP.

In a second aspect, a method of establishing a path is provided, including:

The first node receives the path update message sent by the second node, where the path update message is used to indicate that the attenuation value of the spectrum occupied by the first label switched path LSP in the forwarding neighbor FA link is adjusted, and the first LSP includes the FA a link, the first node is a node on the second LSP, and the second LSP is a FA LSP corresponding to the FA link;

The first node adjusts the attenuation value of the spectrum occupied by the first LSP in the FA link according to the path update message.

In some possible implementations, the path update message carries information about a spectrum occupied by the first LSP, and the spectrum occupied by the first LSP is within a spectrum range of the FA link.

The first node adjusts the attenuation value of the spectrum occupied by the first LSP in the FA link according to the path update message, including:

The first node selects the spectrum occupied by the first LSP from the spectrum of the FA link, and adjusts the attenuation value of the spectrum occupied by the first LSP.

In some possible implementations, the first node adjusts the attenuation value of the spectrum occupied by the first LSP in the FA link according to the path update message, including:

The first node adjusts the attenuation value of the spectrum occupied by the first LSP from a maximum attenuation value to a nominal value.

In some possible implementations, the method further includes:

The first node sends a path update reply message in response to the path update message to the second node.

In a third aspect, a node is provided, comprising any of the possible implementations of the first aspect or the first aspect, or the modules of the second aspect or any of the possible implementations of the second aspect.

In a fourth aspect, a node is provided. The node includes a processor, a memory, and a communication interface. The processor is coupled to the memory and communication interface. The memory is for storing instructions for the processor to execute, and the communication interface is for communicating with other devices under the control of the processor. When the processor executes the instructions stored by the memory, the execution causes the processor to perform the first aspect or any possible implementation of the first aspect, or the method of any of the second aspect or any possible implementation of the second aspect .

A fifth aspect, a computer readable medium for storing a computer program, the computer program comprising any of the possible implementations of the first aspect or the first aspect, or the second or second aspect The instructions of the method in any of the possible implementations.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without paying any creative work.

1a and 1b are schematic diagrams of a network in accordance with one embodiment of the present invention.

2a and 2b are schematic diagrams of a network in accordance with another embodiment of the present invention.

FIG. 3 is a schematic flowchart of a method for establishing a path according to an embodiment of the present invention.

4 is a schematic diagram of a frequency spectrum of an embodiment of the present invention.

FIG. 5 is a schematic diagram of a path message according to an embodiment of the present invention.

FIG. 6 is a schematic flowchart of a method for establishing a path according to another embodiment of the present invention.

7a and 7b are schematic diagrams of a network in accordance with yet another embodiment of the present invention.

FIG. 8 is a schematic flowchart of a method for establishing a path according to still another embodiment of the present invention.

FIG. 9 is a schematic flowchart of a method for establishing a path according to still another embodiment of the present invention.

Figure 10 is a schematic block diagram of a node in accordance with one embodiment of the present invention.

Figure 11 is a schematic block diagram of a node in accordance with another embodiment of the present invention.

FIG. 12 is a schematic structural diagram of a node according to still another embodiment of the present invention.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of the present invention.

The technical solutions of the embodiments of the present invention can be applied to various transmission networks.

The function of the transport network is to deliver traffic to users. The transport network can employ a variety of transport technologies, such as (Synchronous Digital Hierarchy, SDH), Optical Transport Network (OTN), WDM, and the like. Traditional transport networks only contain management planes and data planes. The control plane is introduced in the traditional transport network, and the optical network including the control plane is called Automatically Switched Optical Network (ASON).

FIG. 1a shows a schematic diagram of a network to which the technical solution of the embodiment of the present invention can be applied. As shown in Figure 1a, the network may include a plurality of nodes 101-109 and links between the various nodes.

In the embodiment of the present invention, the node may be a network device in the network, for example, a router or a switch, but the present invention is not limited thereto.

It should be understood that FIG. 1a is only a simplified schematic diagram of an example, and more nodes or other network devices may be included in the network, which are not shown in FIG. 1a.

In the case of no forwarding Adjacency (FA) link, the various sections in Figure 1a The topology obtained by the point is shown in Figure 1b. That is to say, when there is no FA link, the topology obtained by each node in FIG. 1a is the topology formed by each node and physical link of the network. For example, in Figure 1b, the node is abstracted into a square and the physical link is abstracted into a solid line.

The FA is essentially a path. When the path is regarded as a link and is advertised to a network, the advertised link is called the FA link, and the Label Switched Path (LSP) corresponding to the link. It is called FA LSP.

For example, as shown in FIG. 2a, if an LSP has been established in the network, the path is node 101-node 102-node 103-node 104, and has been published as an FA link, then the topology obtained by each node in FIG. 2a is as shown in FIG. 2b is shown. That is to say, after an LSP is issued as an FA link, it will be regarded as a point-to-point link in the network, that is, the above LSP is regarded as a link of the node 101-node 104.

The technical solution of the embodiment of the present invention uses the FA link to establish a path for a service request, thereby improving spectrum resource utilization.

It should be understood that in the various embodiments of the present invention, "first", "second", "third", "fourth", "fifth", etc. are only intended to distinguish different referents in the same embodiment. , no other restrictions.

For example, "first node", "second node", "third node", etc. are merely referring to different nodes in the same embodiment. In addition, the "first node", the "second node", the "third node", and the like in different embodiments are not necessarily the same. For example, in one embodiment, the first node may be the node 101, and the other implementation In an example, the first node can be node 102.

FIG. 3 shows a schematic flow chart of a method of establishing a path according to an embodiment of the present invention. Each node in FIG. 3 may be a node in the above-described nodes 101-109.

301. The first node determines that the first LSP to be established includes an FA link, and the FA LSP corresponding to the FA link is a second LSP.

In the embodiment of the present invention, the first LSP represents an LSP to be established, that is, an LSP that is requested to be established by a service request. For the different scenarios, the first node may obtain the first LSP according to the service request from the client device or the path setup message sent by the upstream node, so as to obtain the routing information of the first LSP, the occupied spectrum information, and the like.

Optionally, in an embodiment of the invention,

The first node receives a service request, where the service request is used to request to establish the first LSP;

The first node acquires the first LSP according to the service request.

Specifically, in this embodiment, the first node is a node that receives a service request, for example, The first node can be node 101. A client device, such as a data center or other device, sends a service request to the first node. The service request can carry the spectrum bandwidth required by the service. In addition, the service request may also include other service related information, such as information of the source device and the target device of the service.

Optionally, after receiving the service request, the first node may calculate a path that can carry the service according to the service request, and obtain the first LSP. The path calculation method can adopt an existing path calculation algorithm.

Optionally, after receiving the service request, the first node may also request other devices to calculate the path. For example, the other device may be a path computing device such as a Path Computation Element (PCE) or a centralized controller. The other device calculates the first LSP and sends it to the first node. Similarly, the path calculation method can adopt an existing path calculation algorithm.

The first node can obtain the first LSP, that is, the routing information of the first LSP and the occupied spectrum information. In this case, the first node is the first node of the first LSP.

In the embodiment of the present invention, the spectrum information occupied by the first LSP indicates which spectrum resource is occupied by the first LSP.

In the embodiment of the present invention, optionally, a piece of spectrum resource is represented by (n, m), where n represents the center frequency of the spectrum, and m represents the width of the spectrum.

For example, as shown in FIG. 4, if the spectrum resource of the fiber link starts to divide the center frequency from 193.1 THz and steps on both sides in units of 6.25 GHz, the center frequency can be expressed as the following equation (1):

f _n =193.1+(n×6.25/1000)(THz) (1)

Where n is an integer, for example, when n=0, the center frequency f ₀ is 193.1 THz; when n=7, the center frequency f ₇ is 193.14375 THz; when n=-8, the center frequency f _-8 is 193.05 THz. m*12.5GHz is the actual spectrum width. Of course, the unit spectrum width of 6.25 GHz can be changed here, that is, the step unit can be set according to the actual capacity of the data plane node. For the idle spectrum resource shown in Figure 4, n = 2, m = 6, which can be expressed as (2, 6).

Optionally, in another embodiment of the present invention,

The first node receives a path setup message sent by the fourth node, where the fourth node is a previous hop node of the first node on the first LSP, and the path setup message is used to establish the first LSP, where The second path setup message carries the spectrum information occupied by the first LSP;

The first node acquires the first LSP according to the path setup message.

Specifically, in this embodiment, the first node is not the first node of the first LSP, and the like In the case that the first node obtains the first LSP according to the fourth node, that is, the path setup message sent by the previous hop node of the first node on the first LSP, thereby acquiring the first LSP. Routing information and occupied spectrum information, etc.

After determining the LSP to be established, that is, the first LSP, the first node determines whether the FA link is included in the first LSP.

Optionally, in an embodiment of the present invention, the first node determines whether the link between the first node and the next hop node, represented as the second node, is an FA link on the first LSP.

After an LSP is advertised as an FA link, the calculated LSP to be established may include the FA link. For example, in the scenario shown in FIGS. 2a and 2b, the LSP between the node 101 and the node 104 calculated by the node 101 may be the node 101-node 104, that is, the next hop of the node 101 is the node 104, the node 101 and the node The link between 104 is an FA link.

The node that is the starting point of the FA link needs to maintain the relationship between the FA link and the FA LSP. Therefore, the node can determine whether the link is an FA link by searching whether a link has a corresponding FA LSP. Optionally, the first node of the FA link may also synchronize the relationship between the FA link and the FA LSP to other devices, such as a PCE, and the PCE determines whether the corresponding link is an FA link and notifies the corresponding first node.

Optionally, in an embodiment of the present invention, in 301, the first node determines that the link between the first node and the second node is an FA link on the first LSP.

Optionally, in an embodiment of the present invention, in 301, the first node determines that the route of the first LSP includes the FA link, and the spectrum occupied by the first LSP is within the spectrum range of the FA link.

It should be understood that, in 301, the first node may also determine that the FA link is included in the first LSP by other means, which is not limited by the present invention.

302. The first node sends a path update message to the at least one node on the second LSP, where the path update message is used to indicate that the attenuation value of the spectrum occupied by the first LSP in the FA link is adjusted.

Specifically, when the FA link is included in the first LSP, the first node starts the FA LSP corresponding to the FA link, that is, the update of the second LSP. The first node sends a path update message corresponding to the FA link to the at least one node on the second LSP, and the node on the second LSP adjusts the attenuation value of the spectrum occupied by the first LSP according to the path update message.

Optionally, in an embodiment of the present invention, the path update message carries information about a spectrum occupied by the first LSP, and the spectrum occupied by the first LSP is within a spectrum range of the FA link.

Optionally, in an embodiment of the present invention, the first node sends the path update message to the third node, where the third node is a next hop node of the first node on the second LSP, The path update message carries the spectrum information occupied by the first LSP.

Specifically, when the link between the first node and the second node is an FA link, the first node starts an LSP corresponding to the FA link, that is, an update of the second LSP. The first node sends a path update message to the third node, that is, the next hop node of the first node, and the third node adjusts the spectrum occupied by the first LSP according to the path update message. Attenuation value.

For example, in the scenario shown in FIG. 2a and FIG. 2b, if the first LSP is the node 101-node 104, the link between the node 101 and the node 104 is an FA link, and the second LSP corresponding to the FA link is a node. 101-Node 102 - Node 103 - Node 104, node 101 is to send a Path Update message to the next hop on the second LSP, node 102, to send a Path Setup message to the next hop on the first LSP, node 104.

Optionally, in an embodiment of the present invention, the first node sends the path update message to each node except the first node on the second LSP, where the path update message carries the spectrum occupied by the first LSP. information.

Specifically, when sending the path update message, the first node may send a path update message to its next hop node on the second LSP, and then send the path update message to the next hop node by the next hop node; The first node may also directly send a path update message to each node on the second LSP except the first node.

303. The first node sends a path setup message to the at least one node on the first LSP, where the path setup message is used to establish the first LSP.

Specifically, when the FA link is included in the first LSP, the first node sends the FA LSP corresponding to the FA link, that is, the update of the second LSP, to the node on the first LSP. A path establishment message corresponding to an LSP. The node on the first LSP establishes the first LSP according to the path setup message.

Optionally, in an embodiment of the present invention, the first node sends the path setup message to the second node, where the first path setup message carries spectrum information occupied by the first LSP.

Specifically, when the link between the first node and the second node is an FA link, the first node sends a path setup message to the second node, and the second node establishes the path according to the path setup message. The first LSP.

Optionally, the first node sends a path update message and a send path setup message, which may be in parallel. The ground can also be serial. That is to say, the first node may simultaneously send the path update message and the send path setup message; or may send the path update message first, and then send the path setup message after receiving the reply message.

Optionally, the path update message and the path setup message may be defined based on the RSVP-TE protocol and may be extended to carry spectrum information. For example, spectrum information can be carried by extending the LSP_REQUIRED_ATTRIBUTES object. For example, the format shown in Fig. 5 can be employed, where n and m represent the corresponding spectrum (n, m).

304. The node on the second LSP adjusts the attenuation value of the spectrum occupied by the first LSP in the FA link according to the path update message.

Specifically, the node that receives the path update message parses the spectrum occupied by the first LSP according to the path update message, that is, the spectrum segment that needs to be adjusted, for example, (n, m), and the node starts filtering of the FA link. And adjust the attenuation value of the spectrum segment.

Optionally, the node selects a spectrum occupied by the first LSP from a spectrum of the FA link, and adjusts an attenuation value of a spectrum occupied by the first LSP.

Optionally, the node adjusts the attenuation value of the spectrum occupied by the first LSP from a maximum attenuation value to a nominal value.

Optionally, the optical signal-to-noise ratio (OSNR) degradation flatness fed back by the downstream node may also be adjusted. Specifically, the present invention is not limited. The purpose of the adjustment is to make the optical performance of the current path suitable for service delivery, and the existing service is not affected by the newly created LSP, and the normal operation cannot be performed.

Optionally, in an embodiment of the present invention, when the node that receives the path update message is not the last node of the second LSP, the node sends a path update to the next hop node of the node on the second LSP. The message that the path update message carries the spectrum information occupied by the first LSP. The next hop node may perform processing similar to the node, and finally, after the last node of the second LSP adjusts the spectrum occupied by the first LSP, it sends a path update reply message to the upstream, and finally to the first node. Send a path update reply message.

Optionally, in an embodiment of the present invention, if the first node directly sends a path update message to each node on the second LSP, each node on the second LSP adjusts the spectrum occupied by the first LSP. A path update reply message can be sent directly to the first node.

It should be understood that the content carried by the path update message of each downstream node may be the same or different, and the attenuation nominal value adjusted by each downstream node may be the same or different. The present invention is not limited thereto.

305. The first node receives a path update reply message in response to the path update message.

306. The first node receives a path setup reply message in response to the path setup message.

The node that receives the path setup message may establish a corresponding cross-connection according to the path setup message, and send a path setup reply message to the first node.

307. The first node determines, according to the path update reply message and the path setup reply message, that the first LSP is established.

Specifically, when the first node is the first node of the first LSP, after receiving the path update reply message and the path setup reply message, the first node determines that the first LSP is established, and then starts to deliver service data. After the first node is not the first node of the first LSP, after receiving the path update reply message and the path setup reply message, the first node determines that the first LSP is established, and sends a path establishment reply to the upstream node. a message, so that the first node of the first LSP determines that the first LSP is established, and then starts to deliver service data.

Optionally, in an embodiment of the present invention, when the link between the first node and the second node is not an FA link, the first node sends a path establishment message to the second node, where the path is established. The message is used to establish the first LSP, and the path setup message carries the spectrum information occupied by the first LSP.

Specifically, when the link between the first node and the second node is not an FA link, the first node sends a path establishment message to the second node, and the second node acquires the path according to the path setup message. The first LSP can be similar to the first node, and is not described here for brevity.

The method for establishing a path in the embodiment of the present invention uses the FA link to establish a path for a service request, so that when the service data is transmitted in the FA link, a small guard band may not be needed or set, thereby improving spectrum resource utilization.

Embodiments of the present invention will be described in detail below with reference to specific examples. It should be noted that these examples are only intended to assist those skilled in the art to better understand the embodiments of the present invention and not to limit the scope of the embodiments of the present invention.

Taking the scenario shown in Figure 2a and Figure 2b as an example, assume the following information:

The spectrum bandwidth of each link in the network is consistent, 500 GHz; the protocols used in the network are RSVP-TE signaling protocol and OSPF-TE routing protocol;

An LSP (LSP ID=LSP1) has been established in the network, and the path is node 101-node 102- Node 103 - Node 104, with a bandwidth of 200 GHz, has been issued as an FA link; the 200 GHz occupied band has a spectral range of: (193.1 THz, 193.3 THz).

Figure 6 is a flow diagram of one embodiment of the scenario shown in Figures 2a and 2b.

601. The node 101 receives a service request of the client device.

It is assumed that the path established by the service request request is LSP2, and the bandwidth of the service is carried in the service request, which is assumed to be 37.5 GHz in this embodiment.

602. Node 101 determines LSP2.

The node 101 calculates, according to the service request, that LSP2 is the node 101-node 104, and the specific spectrum resource information used is (3, 3).

603. The node 101 determines whether the link between the node 101 and the next hop in the LSP2 is an FA link.

In this embodiment, the link between the node 101 and the next hop is the node 101-node 104. The node 101 can determine that the node 101-node 104 is the FA chain according to local information, such as the relationship between the FA link and the FA LSP. The LSP of the FA link corresponding to the FA link is LSP1. Additionally, node 101 can determine that the spectrum occupied by LSP2 is within the spectrum of the FA link.

604. The node 101 sends a path update message to the next hop of the LSP1.

The next hop of LSP1 is node 102. The node 101 carries the spectrum information (3, 3) in the path update message to indicate that the spectrum segment (3, 3) needs to be adjusted. The spectrum information is used for the intermediate node of LSP1 to make corresponding adjustments to ensure that the optical layer damage of the LSP2 path can be within a reasonable range, that is, LSP2 can be successfully established.

605. The node 101 sends a path setup message to the next hop of the LSP2.

The next hop of LSP2 is node 104. The path establishment message may carry the spectrum information used by LSP2, that is, (3, 3).

606. The node 102 performs spectrum adjustment.

The node 102 receives the path update message, and the spectrum segment that needs to be adjusted is (3, 3). Node 102 adjusts the attenuation value of the attenuator of the spectrum segment. In this embodiment, the attenuation maximum value is adjusted to the nominal value; and the adjustment can also be made according to the OSNR degradation flatness of the downstream feedback. Specifically, the present invention is not limited. The purpose of the adjustment is to enable the optical performance of the current path to be suitable for service delivery, and the existing service (the FA has no other existing services in this embodiment) is not subject to the new LSP. The effect is that it does not work properly.

607. The node 102 sends a path update message to the next hop.

Since node 102 is an intermediate node, it also needs to pass a path update message to the downstream node, ie node 102 sends a path update message to node 103.

608, node 103 performs spectrum adjustment.

This step is similar to 606 and will not be described here.

609. The node 103 sends a path update message to the next hop.

This step is similar to 607 and will not be described here.

610. Node 104 performs spectrum adjustment.

The end node 104 receives the path update message and the path setup message sent by the node 101, making a spectrum adjustment similar to step 606.

611. The node 104 sends a path update reply message and a path setup reply message.

The path update reply message can be delivered to the node 101 via the upstream node on LSP1, and the path setup reply message can be sent directly to the node 101.

612. The node 101 determines that the establishment of the LSP2 is completed.

After receiving the path update reply message sent by the node 102 and the path setup reply message sent by the node 104, the head node 101 determines that the establishment of the LSP2 is completed and starts transmitting service data.

A scene graph of another embodiment of the present invention can be as shown in Figures 7a and 7b.

As shown in FIG. 7a, if an LSP has been established in the network, the path is node 102-node 103-node 104, and has been issued as an FA link, the topology obtained by each node in FIG. 7a is as shown in FIG. 7b.

In the scenario shown in Figures 7a and 7b, the following information is assumed:

The spectrum bandwidth of each link in the network is consistent, 500 GHz; the protocols used in the network are RSVP-TE signaling protocol and OSPF-TE routing protocol;

An LSP (LSP ID=LSP1) has been established in the network, and the path is node 102-node 103-node 104, the bandwidth is 100 GHz, and has been issued as the FA link; the spectrum range of the 100 GHz occupied band is: (193.1) THz, 193.2 THz).

Figure 8 is a flow diagram of one embodiment of the scenario shown in Figures 7a and 7b.

801. The node 101 receives a service request of the client device.

It is assumed that the path established by the service request request is LSP2, and the bandwidth of the service is carried in the service request, which is assumed to be 75 GHz in this embodiment.

802, node 101 determines LSP2.

The node 101 calculates, according to the service request, that LSP2 is a node 101-node 102-node 104, The specific spectrum resource information used is (6, 6).

803. The node 101 determines whether the link between the node 101 and the next hop in the LSP2 is an FA link.

In the present embodiment, the link between the node 101 and the next hop is the node 101-node 102. Based on the local information, the node 101 can determine that the node 101-node 102 is not an FA link.

804. The node 101 sends a path setup message to the next hop of the LSP2.

The next hop of LSP2 is node 102. This path setup message is used to establish LSP2.

805. The node 102 determines whether the link between the node 102 and the next hop in the LSP2 is an FA link.

The node 102 receives the path setup message and parses the path setup message to establish a message of LSP2. The node 102 is not a terminal node, so it is necessary to determine whether the link between the node and the next hop is an FA link. In this embodiment, the link between the node 102 and the next hop is the node 102-node 104. The node 102 can determine that the node 102-node 104 is an FA link and the FA corresponding to the FA link according to the local information. The LSP is LSP1. Additionally, node 102 can determine that the spectrum occupied by LSP2 is within the spectrum of the FA link.

806. The node 102 sends a path update message to the next hop of the LSP1.

The next hop of LSP1 is node 103. The node 102 carries spectrum information (6, 6) in the path update message to indicate that the spectrum segment (6, 6) needs to be adjusted. The spectrum information is used for the intermediate node of LSP1 to make corresponding adjustments to ensure that the optical layer damage of the LSP2 path can be within a reasonable range, that is, LSP2 can be successfully established.

807. The node 102 sends a path setup message to the next hop of the LSP2.

The next hop of LSP2 is node 104. The path establishment message may carry the spectrum information used by LSP2, that is, (6, 6).

808, node 103 performs spectrum adjustment.

The node 103 receives the path update message and parses out the spectrum segment to be adjusted (6, 6). Node 103 adjusts the attenuation value of the attenuator of the spectrum segment. In this embodiment, the attenuation maximum value is adjusted to the nominal value; and the adjustment can also be made according to the OSNR degradation flatness of the downstream feedback. Specifically, the present invention is not limited. The purpose of the adjustment is to enable the optical performance of the current path to be suitable for service delivery, and the existing service (the FA has no other existing services in this embodiment) is not subject to the new LSP. The effect is that it does not work properly.

809. The node 103 sends a path update message to the next hop.

Since node 103 is an intermediate node, it also needs to pass a path update message to the downstream node, ie node 103 sends a path update message to node 104.

At 810, node 104 performs spectrum adjustment.

The end node 104 receives the path update message and the path setup message sent by the node 102, doing a spectrum adjustment similar to step 808.

811. The node 104 sends a path update reply message and a path setup reply message.

The path update reply message can be passed to node 102, and the path setup reply message can be sent directly to node 102.

812. The node 102 sends a path setup reply message to the upstream node.

After receiving the path update reply message sent by the node 103 and the path setup reply message sent by the node 104, the node 102 determines that the LSP2 is established. Because it is not the first node, it also needs to send a path setup reply message to the upstream node, that is, the node 102 to the node. 101 sends a path setup reply message.

Optionally, if the establishment of the LSP2 fails, for example, the new service cannot be established without affecting other existing services, the node 102 receives the path update failure message sent by the node 103, and may send the path to the upstream node, that is, the node 101. Establish a failure message.

813. The node 101 determines that the establishment of the LSP2 is completed.

After receiving the path setup reply message sent by the node 102, the head node 101 determines that the establishment of the LSP2 is completed and starts transmitting service data.

Figure 6 and Figure 8 show the process of parallel processing of two LSPs (LSP1 and LSP2). These processes are suitable for the performance of existing network services, such as the performance of the Bit Error Rate (BER) performance is higher than the threshold. The measured BER value and threshold of the service can be configured to each node through a network management system or other means.

When the BER of the service is below the threshold, it can be serialized.

Taking the scenario shown in Figures 7a and 7b as an example, assume the following information:

Assume that the spectrum bandwidth of each link in the network is consistent, 500 GHz; the protocols used in the network are RSVP-TE signaling protocol and OSPF-TE routing protocol;

An LSP (LSP ID=LSP1) has been established in the network, and node 102-node 103-node 104 has a bandwidth of 100 GHz and has been issued as an FA link.

There is already another LSP2 (node 102-node 104) in the network, which uses LSP1 with a bandwidth of 25 GHz and an occupied spectrum of (2, 2). The current actual BER threshold is low within the spectrum of the FA link. At the set threshold.

Figure 9 is a flow chart of this embodiment.

901. The node 101 receives a service request of the client device.

It is assumed that the path established by the service request request is LSP3, and the bandwidth of the service is carried in the service request, which is assumed to be 75 GHz in this embodiment.

902. Node 101 determines LSP3.

Based on the service request, the node 101 calculates that the LSP3 is the node 101-node 102-node 104, and the spectrum resource information used is (10, 6).

903. The node 101 determines whether the link between the node 101 and the next hop in the LSP3 is an FA link.

In the present embodiment, the link between the node 101 and the next hop is the node 101-node 102. Based on the local information, the node 101 can determine that the node 101-node 102 is not an FA link.

904. The node 101 sends a path setup message to the next hop of the LSP3.

The next hop of LSP3 is node 102. This path setup message is used to establish LSP3.

905. The node 102 determines whether the link between the node 102 and the next hop in the LSP3 is an FA link.

The node 102 receives the path setup message and parses the path setup message to establish a message of LSP3. The node 102 is not a terminal node, so it is necessary to determine whether the link between the node and the next hop is an FA link. In this embodiment, the link between the node 102 and the next hop is the node 102-node 104. The node 102 can determine that the node 102-node 104 is an FA link and the FA corresponding to the FA link according to the local information. The LSP is LSP1. Additionally, node 102 can determine that the spectrum occupied by LSP3 is within the spectrum of the FA link.

906, the node 102 determines that the BER threshold of the LSP2 is lower than the set value, and then performs step 907.

907. The node 102 sends a path update message to the next hop of the LSP1.

The next hop of LSP1 is node 103. The node 102 carries the spectrum information (10, 6) in the path update message to indicate that the spectrum segment (10, 6) needs to be adjusted. The spectrum information is used for the intermediate node of the LSP1 to make corresponding adjustments to ensure that the optical layer damage of the LSP3 path can be within a reasonable range, that is, the LSP3 can be successfully established.

At 908, node 103 performs spectrum adjustment.

The node 103 receives the path update message and parses out the spectrum segment to be adjusted (10, 6). Node 103 adjusts the attenuation value of the attenuator of the spectrum segment.

909, node 103 sends a path update message to the next hop.

Since node 103 is an intermediate node, it also needs to pass a path update message to the downstream node, ie node 103 sends a path update message to node 104.

910. Node 104 performs spectrum adjustment.

The end node 104 receives the path update message and does a spectrum adjustment similar to step 908.

911, the node 104 sends a path update reply message to the upstream node.

The path update reply message can be passed to the node 102 through the upstream node.

912. The node 102 sends a path setup message to the next hop of the LSP3.

After receiving the path update reply message of the downstream node 103, the node 102 sends a path setup message to the next hop of the LSP3 path, that is, the node 104, in which the spectrum information used by the LSP3 can be carried in the path setup message, that is, (10, 6) ).

913. The node 104 sends a path setup reply message to the node 102.

The last node 104 receives the path establishment message of LSP3, establishes a cross-connection, and then returns a path establishment reply message indicating that the path establishment is successful.

914. The node 102 sends a path setup reply message to the upstream node.

After receiving the path setup reply message sent by the node 104, the node 102 also needs to send a path setup reply message to the upstream node because it is not the first node, that is, the node 102 sends a path setup reply message to the node 101.

915. The node 101 determines that the establishment of the LSP3 is completed.

After receiving the path setup reply message sent by the node 102, the head node 101 determines that the establishment of the LSP3 is completed, and starts transmitting service data.

In the above solution, the serial method is adopted, and the success rate of path establishment can be improved when the BER value of the existing service is lower than the threshold.

It should be understood that, in various embodiments of the present invention, the size of the sequence numbers of the above processes does not mean the order of execution, and the order of execution of each process should be determined by its function and internal logic, and should not be taken to the embodiments of the present invention. The implementation process constitutes any limitation.

A method of establishing a path according to an embodiment of the present invention is described in detail above, and a node according to an embodiment of the present invention will be described below.

Figure 10 shows a schematic block diagram of a node 1000 in accordance with one embodiment of the present invention.

It should be understood that the node 1000 may correspond to nodes in various method embodiments and may have any functionality of the nodes in the method.

As shown in FIG. 10, the node 1000 includes:

The processing module 1010 is configured to determine that the first label switching path LSP to be established includes a forwarding neighbor FA link, and the FA LSP corresponding to the FA link is a second LSP.

The transceiver module 1020 is configured to send a path update message to the at least one node on the second LSP, where the path update message is used to indicate that the attenuation value of the spectrum occupied by the first LSP in the FA link is adjusted, and the At least one node on an LSP sends a path setup message, and the path setup message is used to establish the first LSP.

The node in the embodiment of the present invention uses the FA link to establish a path for the service request. Therefore, when the service data is transmitted in the FA link, a small guard band may not be needed or may be used, thereby improving spectrum resource utilization.

Optionally, in an embodiment of the present invention, the processing module 1010 is specifically configured to determine, on the first LSP, that the link between the node and the second node is the FA link, where the second The node is the next hop node of the node on the first LSP.

Optionally, in an embodiment of the present invention, the processing module 1010 is further configured to: determine that the route of the first LSP includes the FA link, and the spectrum occupied by the first LSP is within a spectrum of the FA link. .

Optionally, in an embodiment of the present invention, the transceiver module 1020 is specifically configured to send the path update message to a third node, where the third node is a next hop node of the node on the second LSP. The path update message carries the spectrum information occupied by the first LSP.

Optionally, in an embodiment of the present invention, the transceiver module 1020 is specifically configured to send the path update message to each node except the node on the second LSP, where the path update message carries the first LSP occupation. Spectrum information.

Optionally, in an embodiment of the present invention, the transceiver module 1020 is configured to send the path setup message to the second node, where the first path setup message carries spectrum information occupied by the first LSP.

Optionally, in an embodiment of the present invention, the transceiver module 1020 is further configured to: receive a path update reply message in response to the path update message; and receive a path setup reply message in response to the path setup message;

The processing module 1010 is further configured to determine, according to the path update reply message and the first path setup reply message, that the first LSP is established.

Optionally, in an embodiment of the present invention, the processing module 1010 is further configured to obtain the first LSP according to the received service request or a path setup message used to establish the first LSP. Routing information and occupied spectrum information.

FIG. 11 shows a schematic block diagram of a node 1100 in accordance with another embodiment of the present invention.

It should be understood that the node 1100 may correspond to nodes in various method embodiments and may have any functionality of the nodes in the method.

As shown in FIG. 11, the node 1100 includes:

The transceiver module 1110 is configured to receive a path update message sent by the second node, where the path update message is used to indicate that the attenuation value of the spectrum occupied by the first label switching path LSP in the forwarding neighbor FA link is adjusted, the first LSP Including the FA link, the node is a node on the second LSP, and the second LSP is a FA LSP corresponding to the FA link;

The processing module 1120 is configured to adjust, according to the path update message, an attenuation value of a spectrum occupied by the first LSP in the FA link.

Optionally, in an embodiment of the present invention, the path update message carries information about a spectrum occupied by the first LSP, and a spectrum occupied by the first LSP is within a spectrum range of the FA link;

The processing module 1120 is specifically configured to: select a spectrum occupied by the first LSP from a spectrum of the FA link, and adjust an attenuation value of a spectrum occupied by the first LSP.

Optionally, in an embodiment of the present invention, the processing module 1120 is specifically configured to adjust the attenuation value of the spectrum occupied by the first LSP from a maximum attenuation value to a nominal value.

Optionally, in an embodiment of the present invention, the transceiver module 1110 is further configured to send, to the second node, a path update reply message that is responsive to the path update message.

FIG. 12 shows a structure of a node according to still another embodiment of the present invention, including at least one processor 1202 (eg, a CPU), at least one network interface 1205 or other communication interface, a memory 1206, and at least one communication bus 1203. To achieve connection communication between these components. The processor 1202 is configured to execute executable modules, such as computer programs, stored in the memory 1206. The memory 1206 may include a high speed random access memory (RAM), and may also include a non-volatile memory such as at least one disk memory. A communication connection with at least one other device is achieved by at least one network interface 1205, which may be wired or wireless.

In some embodiments, the memory 1206 stores a program 12061, and the processor 1202 executes the program 12061 for performing the various methods of the aforementioned embodiments of the present invention.

The embodiment of the present invention further provides a network, which may include nodes in the foregoing embodiments.

Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both, for clarity of hardware and software. Interchangeability, the composition and steps of the various examples have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods for implementing the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present invention.

A person skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working process of the system, the device and the unit described above can refer to the corresponding process in the foregoing method embodiment, and details are not described herein again.

In the several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, or an electrical, mechanical or other form of connection.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the embodiments of the present invention.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a standalone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention contributes in essence or to the prior art, or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium. Including a plurality of instructions for causing a computer device (which may be a personal computer, server, or network device, etc.) to perform all or part of the methods of the various embodiments of the present invention Step by step. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, and the like. .

The above is only the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any equivalent person can be easily conceived within the technical scope of the present invention by any person skilled in the art. Modifications or substitutions are intended to be included within the scope of the invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims (24)

1. A method for establishing a path, comprising:

   The first node determines that the first label switching path LSP to be established includes forwarding a neighboring FA link, and the FA LSP corresponding to the FA link is a second LSP;

   The first node sends a path update message to the at least one node on the second LSP, where the path update message is used to indicate that the attenuation value of the spectrum occupied by the first LSP in the FA link is adjusted;

   The first node sends a path setup message to at least one node on the first LSP, where the path setup message is used to establish the first LSP.
2. The method according to claim 1, wherein the first node determines that the first label switching path LSP to be established includes a forwarding neighbor FA link, including:

   Determining, by the first node, that the link between the first node and the second node is the FA link, where the second node is the first node The next hop node on the first LSP.
3. The method according to claim 2, wherein the first node determines that the first label switching path LSP to be established includes a forwarding neighbor FA link, and further includes:

   The first node determines that the route of the first LSP includes the FA link, and the spectrum occupied by the first LSP is within the spectrum range of the FA link.
4. The method according to claim 2 or 3, wherein the first node sends a path update message to at least one node on the second LSP, including:

   The first node sends the path update message to a third node, where the third node is a next hop node of the first node on the second LSP, and the path update message carries the Spectrum information occupied by the first LSP.
5. The method according to claim 2 or 3, wherein the first node sends a path update message to at least one node on the second LSP, including:

   The first node sends the path update message to each node except the first node on the second LSP, where the path update message carries spectrum information occupied by the first LSP.
6. The method according to any one of claims 2 to 5, wherein the first node sends a path establishment message to at least one node on the first LSP, including:

   The first node sends the path setup message to the second node, where the first path setup message carries spectrum information occupied by the first LSP.
7. The method according to any one of claims 1 to 6, wherein the method further comprises:

   The first node receives a path update reply message in response to the path update message;

   The first node receives a path setup reply message in response to the path setup message;

   The first node determines, according to the path update reply message and the first path setup reply message, that the first LSP is established.
8. The method according to any one of claims 1 to 7, wherein the method further comprises:

   The first node acquires routing information of the first LSP and occupied spectrum information according to the received service request or the path establishment message used to establish the first LSP.
9. A method for establishing a path, comprising:

   The first node receives the path update message sent by the second node, where the path update message is used to indicate that the attenuation value of the spectrum occupied by the first label switched path LSP in the forwarding neighbor FA link is adjusted, where the first LSP includes The FA link, the first node is a node on the second LSP, and the second LSP is a FA LSP corresponding to the FA link;

   And the first node adjusts, according to the path update message, an attenuation value of a spectrum occupied by the first LSP in the FA link.
10. The method according to claim 9, wherein the path update message carries information about a spectrum occupied by the first LSP, and a spectrum occupied by the first LSP is within a spectrum range of the FA link;

    And the first node, according to the path update message, adjusting an attenuation value of a spectrum occupied by the first LSP in the FA link, including:

    The first node selects a spectrum occupied by the first LSP from a spectrum of the FA link, and adjusts an attenuation value of a spectrum occupied by the first LSP.
11. The method according to claim 9 or 10, wherein the first node adjusts the attenuation value of the spectrum occupied by the first LSP in the FA link according to the path update message, including:

    The first node adjusts an attenuation value of a spectrum occupied by the first LSP from a maximum attenuation value to a nominal value.
12. The method according to any one of claims 9 to 11, wherein the method further comprises:

    The first node sends a path update reply message in response to the path update message to the second node.
13. A node, comprising:

    a processing module, configured to determine that the first label switching path LSP to be established includes a forwarding neighbor FA link, and the FA LSP corresponding to the FA link is a second LSP;

    a transceiver module, configured to send a path update message to at least one node on the second LSP, where the path update message is used to indicate that an attenuation value of a spectrum occupied by the first LSP in the FA link is adjusted, and And sending a path setup message to the at least one node on the first LSP, where the path setup message is used to establish the first LSP.
14. The node according to claim 13, wherein the processing module is specifically configured to: determine, on the first LSP, that the link between the node and the second node is the FA link, where The second node is a next hop node of the node on the first LSP.
15. The node according to claim 14, wherein the processing module is further configured to: determine that the route of the first LSP includes the FA link, and the spectrum occupied by the first LSP is in the FA chain Within the spectrum of the road.
16. The node according to claim 13 or 14, wherein the transceiver module is specifically configured to send the path update message to a third node, wherein the third node is the node in the second The next hop node on the LSP, the path update message carries spectrum information occupied by the first LSP.
17. The node according to claim 13 or 14, wherein the transceiver module is configured to send the path update message to each node except the node on the second LSP, where the path is updated. The message carries the spectrum information occupied by the first LSP.
18. The node according to any one of claims 13 to 17, wherein the transceiver module is specifically configured to send the path establishment message to the second node, where the first path setup message carries the Spectrum information occupied by the first LSP.
19. The node according to any one of claims 12 to 18, wherein the transceiver module is further configured to: receive a path update reply message in response to the path update message; and receive a path establishment response to the path establishment message Reply message;

    The processing module is further configured to determine, according to the path update reply message and the first path setup reply message, that the first LSP is established.
20. A node according to any one of claims 12 to 19, wherein said node The processing module is further configured to obtain the routing information of the first LSP and the occupied spectrum information according to the received service request or the path establishment message used to establish the first LSP.
21. A node, comprising:

    a transceiver module, configured to receive a path update message sent by the second node, where the path update message is used to indicate that the attenuation value of the spectrum occupied by the first label switching path LSP in the forwarding neighbor FA link is adjusted, the first The LSP includes the FA link, the node is a node on the second LSP, and the second LSP is a FA LSP corresponding to the FA link;

    And a processing module, configured to adjust, according to the path update message, an attenuation value of a spectrum occupied by the first LSP in the FA link.
22. The node according to claim 21, wherein the path update message carries information about a spectrum occupied by the first LSP, and a spectrum occupied by the first LSP is within a spectrum range of the FA link;

    The processing module is specifically configured to: select a spectrum occupied by the first LSP from a spectrum of the FA link, and adjust an attenuation value of a spectrum occupied by the first LSP.
23. The node according to claim 21 or 22, wherein the processing module is configured to adjust an attenuation value of a spectrum occupied by the first LSP from a maximum attenuation value to a nominal value.
24. The node according to any one of claims 21 to 23, wherein the transceiver module is further configured to send a path update reply message in response to the path update message to the second node.

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