WO2012163015A1 - Procédé et dispositif de calcul de chemin - Google Patents

Procédé et dispositif de calcul de chemin Download PDF

Info

Publication number
WO2012163015A1
WO2012163015A1 PCT/CN2011/081024 CN2011081024W WO2012163015A1 WO 2012163015 A1 WO2012163015 A1 WO 2012163015A1 CN 2011081024 W CN2011081024 W CN 2011081024W WO 2012163015 A1 WO2012163015 A1 WO 2012163015A1
Authority
WO
WIPO (PCT)
Prior art keywords
path
lower wavelength
center frequency
interfaces
available center
Prior art date
Application number
PCT/CN2011/081024
Other languages
English (en)
Chinese (zh)
Inventor
资小兵
Original Assignee
华为技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 华为技术有限公司 filed Critical 华为技术有限公司
Priority to PCT/CN2011/081024 priority Critical patent/WO2012163015A1/fr
Priority to CN201180002216.6A priority patent/CN102439886B/zh
Publication of WO2012163015A1 publication Critical patent/WO2012163015A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0227—Operation, administration, maintenance or provisioning [OAMP] of WDM networks, e.g. media access, routing or wavelength allocation
    • H04J14/0254—Optical medium access
    • H04J14/0256—Optical medium access at the optical channel layer
    • H04J14/0257—Wavelength assignment algorithms

Definitions

  • Embodiments of the present invention relate to the field of communications and, more particularly, to methods and apparatus for path computation. Background technique
  • a wavelength division multiplexing network consists of nodes and links, and the two nodes are connected by links. Multiple wavelength channels can be carried in a fiber link, and wavelength channels in different fiber links can be connected by nodes. Therefore, a particular wavelength connection can be connected from the source node to the sink node via one or more fiber links.
  • the wavelength connection can be either unidirectional or bidirectional. Since each fiber link can transmit multiple wavelengths, the transmission capacity is relatively large.
  • the wavelength connection requires the use of spectrum resources in the fiber link, and the available spectrum resources in each fiber link are limited.
  • the available spectrum resources in the fiber link are generally divided into fixed frequency grids, each of which can serve as a wavelength channel.
  • small-granularity and large-grained (such as 10 Gigabits per second (Gbps) and 1 terabits per second (Tbps)) services use wavelength-connected hybrid transmission, fiber links are required.
  • the spectrum resources in the division divide the wavelength channels according to a large spectrum interval, for example, 100 gigahertz (GHz) intervals, to meet the needs of large-granular services.
  • GHz gigahertz
  • usually small granularity services do not require such large spectral spacing. Larger spectral spacing means fewer available wavelength channels, thus reducing the utilization of spectrum resources in the fiber link.
  • the spectrum resources in the fiber link may be divided into wavelength channels without a fixed interval, and the spectrum bandwidth of the wavelength connection may be adjusted according to service requirements.
  • the required spectral bandwidth for each wavelength connection is related to the modulation format of the upper and lower wavelength interfaces at both ends, and the modulation format required for the upper and lower wavelength interfaces is related to the path length, the number of path hops, the type of fiber, and the granularity of the service.
  • Such a wavelength division multiplexing network is a network that supports a flexible grid.
  • the frequency range assigned to a wavelength connection is called a frequency slot
  • the width of the frequency range, that is, the spectrum bandwidth is called a slot width.
  • the embodiment of the invention provides a method and a device for calculating a path, which can automatically acquire topology information of a flexible grid network, thereby automatically determining a path and allocating spectrum resources for the path.
  • a path calculation method including: acquiring an interface number of a wavelength division multiplexing link in a network, an unavailable frequency range of a wavelength division multiplexing link, an interface number of a first upper and lower wavelength interface, and a second The interface number of the upper and lower wavelength interfaces, the available center frequency of the first upper and lower wavelength interfaces, the spectrum bandwidth of the first upper and lower wavelength interfaces, the available center frequency of the second upper and lower wavelength interfaces, and the spectrum bandwidth of the second upper and lower wavelength interfaces; based on wavelength division multiplexing The interface number of the link, the interface number of the first upper and lower wavelength interfaces, and the interface number of the second upper and lower wavelength interfaces determine the path between the first upper and lower wavelength interfaces and the second upper and lower wavelength interfaces; the wavelength division multiplexing chain passing through the path The unavailable frequency range of the path, the available center frequency of the first upper and lower wavelength interfaces, the available center frequency of the second upper and lower wavelength interfaces, the spectral bandwidth of the first upper and lower wavelength interfaces
  • a path calculation method including: acquiring an interface number of a wavelength division multiplexing link in a network, an available center frequency of a wavelength division multiplexing link, an interface number of a first upper and lower wavelength interface, and a second The interface number of the upper and lower wavelength interfaces, the available center frequency of the first upper and lower wavelength interfaces, the spectrum bandwidth of the first upper and lower wavelength interfaces, the available center frequency of the second upper and lower wavelength interfaces, and the spectrum bandwidth of the second upper and lower wavelength interfaces; based on wavelength division multiplexing The interface number of the link, the interface number of the first upper and lower wavelength interfaces, and the interface number of the second upper and lower wavelength interfaces determine the path between the first upper and lower wavelength interfaces and the second upper and lower wavelength interfaces; the wavelength division multiplexing chain passing through the path The unavailable frequency range of the path, the available center frequency of the WDM link through which the path passes, the available center frequency of the first upper and lower wavelength interfaces, the available center frequency of the second upper and lower wavelength interfaces
  • an apparatus for path calculation including: an acquiring unit, configured to acquire an interface number of a wavelength division multiplexing link in a network, an unavailable frequency range of a wavelength division multiplexing link, and a first uplink and downlink wavelength interface. Interface number, the interface number of the second upper and lower wavelength interfaces, the available center frequency of the first upper and lower wavelength interfaces, and the spectrum bandwidth of the first upper and lower wavelength interfaces, the available center frequency of the second upper and lower wavelength interfaces, and the spectrum bandwidth of the second upper and lower wavelength interfaces.
  • Determining a path unit configured to determine an interface number based on the wavelength division multiplexing link, an interface number of the first upper and lower wavelength interfaces, and an interface number of the second upper and lower wavelength interfaces to determine between the first upper and lower wavelength interfaces and the second upper and lower wavelength interfaces a path; an allocation unit, an unusable frequency range, a first upper and lower wavelengths of the wavelength division multiplexing link that passes through the path.
  • the available center frequency of the interface, the available center frequency of the second upper and lower wavelength interfaces, the spectral bandwidth of the first upper and lower wavelength interfaces, and the spectral bandwidth of the second upper and lower wavelength interfaces allocate a center frequency for the path.
  • an apparatus for path calculation including: an acquiring unit, configured to acquire an interface number of a wavelength division multiplexing link in a network, an available center frequency of a wavelength division multiplexing link, and a first upper and lower wavelength interface The interface number, the interface number of the second upper and lower wavelength interfaces, the available center frequency of the first upper and lower wavelength interfaces, the spectrum bandwidth of the first upper and lower wavelength interfaces, the available center frequency of the second upper and lower wavelength interfaces, and the spectrum bandwidth of the second upper and lower wavelength interfaces; Determining a path unit, configured to determine a path between the first upper and lower wavelength interfaces and the second upper and lower wavelength interfaces based on the interface number of the wavelength division multiplexing link, the interface number of the first upper and lower wavelength interfaces, and the interface number of the second upper and lower wavelength interfaces An allocation unit, an unavailable frequency range for the wavelength division multiplexing link that passes through the path, an available center frequency of the wavelength division multiplexing link through which the path passes, an available center frequency of the first upper
  • the method and apparatus for path calculation in the embodiment of the present invention can automatically acquire topology information of a flexible grid network, thereby automatically calculating a link path and allocating available spectrum resources to the flexible grid network.
  • FIG. 1 is a flow chart of a method of path computation in accordance with one embodiment of the present invention.
  • FIG. 2 is a flow chart of a method of path computation in accordance with another embodiment of the present invention.
  • Figure 3 is a schematic diagram of the topology of a flexible grid network.
  • FIG. 4 schematically shows the spectral resources of the fiber link.
  • FIGS. 5 through 8 illustrate the available center frequencies for Link 1 through Link 4, respectively.
  • the view of Figure 9 illustrates the spectral bandwidth sub-TLV format.
  • Fig. 10 illustrates the format of the path hopping spectrum bandwidth sub-TLV.
  • FIG. 11 illustrates the format of the path length spectral bandwidth sub-TLV.
  • FIG. 13 is a schematic structural diagram of an apparatus for path calculation according to an embodiment of the present invention.
  • Figure 14 is a block diagram showing the structure of an allocation unit in a device for path calculation according to an embodiment of the present invention.
  • FIG. 15 is a schematic structural diagram of an apparatus for path calculation according to another embodiment of the present invention. detailed description
  • a method for path calculation according to an embodiment of the present invention includes:
  • the interface number of the wavelength division multiplexing link in the network the unavailable frequency range of the wavelength division multiplexing link, the interface number of the first upper and lower wavelength interfaces, the interface number of the second upper and lower wavelength interfaces, and the first upper and lower wavelength interfaces.
  • the link information of a node includes at least one of a local/remote interface number of the node, an available center frequency, and an available frequency range, and a spectrum bandwidth of the upper and lower wavelength interfaces.
  • link state broadcast (LSA, Link State Advertisement) is used to carry the link information
  • OSPF Open Shortest Path First route flooding mechanism is used to distribute the LSA to other nodes.
  • the LSA carries the link TLV (Type/Length/Value).
  • the link TLV carries the local/remote interface number sub-TLV, the available center frequency sub-TLV, and the available frequency range sub-TLV.
  • the topology information of the network can be obtained by collecting the link information of each node advertised by the OSPF route flooding mechanism, and the topology information is saved locally.
  • the first upper and lower wavelength interfaces and the second upper and lower wavelength interfaces are determined according to the interface number of the wavelength division multiplexing link, the interface number of the first upper and lower wavelength interfaces, and the interface number of the second upper and lower wavelength interfaces. The path between.
  • the path between the two upper and lower wavelength interfaces is realized by light-electric-light
  • each potential path between the upper and lower wavelength interfaces can be determined. Specifically, the local interface in the link information of each node is connected to the remote interface to determine a path that can connect two upper and lower wavelength interfaces.
  • the spectral bandwidth of the wavelength interface is the path allocation center frequency.
  • the first is based on an unavailable frequency range of each wavelength division multiplexing link in the path, an available center frequency of the first upper and lower wavelength interfaces, an available center frequency of the second upper and lower wavelength interfaces, a spectrum bandwidth of the first upper and lower wavelength interfaces, and The spectral bandwidth of the second upper and lower wavelength interfaces determines whether the path has an available center frequency, and then one of these available center frequencies is selected as the center frequency of the path.
  • one of the available center frequencies of the first upper and lower wavelength interfaces and the available center frequency of the second upper and lower wavelength interfaces may be selected first.
  • the frequency range of the path is determined based on the selected available center frequency and the spectral bandwidth of the upper and lower wavelength interfaces.
  • the spectrum bandwidth of the first upper and lower wavelength interfaces is equal to the spectrum bandwidth of the second upper and lower wavelength interfaces, so the spectrum bandwidth of the upper and lower wavelength interfaces is the spectrum bandwidth of the first upper and lower wavelength interfaces.
  • the spectrum bandwidth of the first upper and lower wavelength interfaces is not equal to the spectrum bandwidth of the second upper and lower wavelength interfaces, the spectrum bandwidth of the upper and lower wavelength interfaces is the larger one of the spectrum bandwidth of the first upper and lower wavelength interfaces and the spectrum bandwidth of the second upper and lower wavelength interfaces. . Finally, it is determined whether the frequency range overlaps with the unavailable frequency range of the wavelength division multiplexed link through which the path passes. If there is no overlapping portion, it is determined that the selected available center frequency is the available center frequency of the path.
  • the frequency range is usually defined by its end value, for example, the selected available center frequency is subtracted from half of the frequency bandwidth of the upper and lower wavelength interfaces, and the selected available center frequency plus half of the frequency bandwidth of the upper and lower wavelength interfaces is used as the frequency.
  • the end value of the range for example, the selected available center frequency is subtracted from half of the frequency bandwidth of the upper and lower wavelength interfaces, and the selected available center frequency plus half of the frequency bandwidth of the upper and lower wavelength interfaces is used as the frequency.
  • the spectrum bandwidth of the upper and lower wavelength interfaces is adjustable according to different path attributes such as path hop count, path length or fiber type. Therefore, when the center frequency is allocated to the path, the spectrum bandwidth of the upper and lower wavelength interfaces is first searched according to the path attribute, and then the center frequency of the path is determined according to the spectrum bandwidth of the upper and lower wavelength interfaces and the available center frequency of the wavelength division multiplexing link.
  • the path calculation method of the embodiment of the present invention can automatically acquire the topology information of the flexible grid network, thereby automatically calculating the link path and allocating available spectrum resources for the flexible grid network.
  • a method for path calculation according to another embodiment of the present invention includes:
  • the path between the first upper and lower wavelength interfaces and the second upper and lower wavelength interfaces is determined based on the interface number of the wavelength division multiplexing link, the interface number of the first upper and lower wavelength interfaces, and the interface number of the second upper and lower wavelength interfaces.
  • an available center frequency of the wavelength division multiplexing link based on the path an available center frequency of the first upper and lower wavelength interfaces, an available center frequency of the second upper and lower wavelength interfaces, a spectrum bandwidth of the first upper and lower wavelength interfaces, and a second upper and lower wavelengths
  • the spectrum bandwidth of the interface is the path allocation center frequency.
  • the available center frequency of the path should be the coincident portion of the available center frequencies of the links through which the path passes.
  • the available center frequency of the first upper and lower wavelength interfaces For example, first, based on the available center frequency of the wavelength division multiplexing link through which the path passes, the available center frequency of the first upper and lower wavelength interfaces, the available center frequency of the second upper and lower wavelength interfaces, the spectrum bandwidth of the first upper and lower wavelength interfaces, and the second upper and lower
  • the spectral bandwidth of the wavelength interface determines whether the path has an available center frequency and then selects one of these available center frequencies as the center frequency of the path.
  • one of the available center frequencies of the first upper and lower wavelength interfaces and the available center frequencies of the second upper and lower wavelength interfaces and the available center frequencies of the wavelength division multiplexed links through which the paths pass are selected.
  • Subtracting the selected available center frequency by half of the frequency bandwidth of the upper and lower wavelength interfaces, and selecting the available center frequency plus half of the frequency bandwidth of the upper and lower wavelength interfaces as the end value of the frequency range, and the spectrum of the first upper and lower wavelength interfaces When the bandwidth is equal to the spectrum bandwidth of the second upper and lower wavelength interfaces, the spectrum bandwidth of the upper and lower wavelength interfaces is the spectrum bandwidth of the first upper and lower wavelength interfaces.
  • the spectrum bandwidth of the wavelength interface is the larger one of the spectrum bandwidth of the first upper and lower wavelength interfaces and the spectrum bandwidth of the second upper and lower wavelength interfaces. It is determined whether the frequency range and the unavailable frequency range of the wavelength division multiplexing link through which the path passes have a coincidence portion.
  • the range of unavailable frequencies of the wavelength division multiplexed link through which the path passes may be obtained from the available center frequency of the wavelength division multiplexed link through which the path passes.
  • Wave division The entire frequency range of the link is formed by the available frequency range and the unavailable frequency range in the link, and the available center frequency is the frequency of the interval unit spectral bandwidth in the available frequency range. If there is no coincident portion, it is determined that the selected available center frequency is the available center frequency of the path. Select one of the available center frequencies of the path as the center frequency of the path.
  • Obtaining the spectrum bandwidth of the upper and lower wavelength interfaces further includes obtaining the spectrum bandwidth of the upper and lower wavelength interfaces according to the path attribute, where the path attribute includes the path hop count, the path length, or the fiber type.
  • the path calculation method of the embodiment of the present invention can automatically acquire the topology information of the flexible grid network, thereby automatically calculating the link path and allocating available spectrum resources to the flexible grid network.
  • Figure 3 is a schematic diagram of the topology of a flexible grid network. Taking the network shown in Figure 3 as an example, the automatic acquisition of the topology information of the flexible grid network is described, and the automatic calculation of the path and the allocation of the spectrum resources are realized based on the obtained topology information.
  • the network consists of node A, node B, node C, and node D. Lines between nodes represent fiber links.
  • Interface 1 is an upper and lower wavelength interface of node A
  • interface 6 is an upper and lower wavelength interface of node C.
  • “upper” represents the transmitting end of the wavelength, usually a laser;
  • “lower” represents the receiving end of the wavelength.
  • the upper and lower wavelength interfaces 1 and the upper and lower wavelength interfaces 6 are interfaces that can transmit and receive wavelengths. For the service direction from interface 1 to interface 6, interface 1 is the upper interface and interface 6 is the lower interface.
  • Figure 4 is a schematic representation of the spectral resources of a fiber optic link.
  • the frequency resource in the fiber link is divided into the center frequency from 193.1 THz, and the center frequency is stepwisely divided into 6.25 GHz units, that is, the division of the spectrum resources in the fiber link is as shown in FIG. 4 .
  • the center frequency can be calculated according to the following formula:
  • f (THz) 193.1 (THz) + ( n * 6.25/1000 ) (THz) ⁇ Equation 1
  • f denotes the center frequency of the fiber link
  • n is an integer
  • Inl denotes the current center frequency distance
  • the center frequency of Inl units (6.25 GHz in this example) exists between the initial center frequency (193.1 THz in this example).
  • the network in this embodiment has four links, namely, link 1 to link 4.
  • link 1 to link 4 are both wavelength division multiplexed links, so multiple wavelength signals can be transmitted simultaneously.
  • 5 to 8 respectively show the available center frequencies of the respective links, wherein the boldly illustrated frequency portion is the unavailable frequency range, and the unavailable frequency range and the available frequency range constitute the entire frequency range of the link.
  • the available center frequencies for link 1 through link 4 are determined as follows: If the frequency range of at least units (eg, 6.25 GHz) on both sides of the center frequency is idle, the center frequency is considered to be the available center frequency.
  • the available center frequency of link 1 corresponds to an integer value of -8 to 0 and an integer of 6 to 12, and the available frequency range of link 1 is n from -9 to 1 and from 5 to The frequency range between 13; the available center frequency of link 2 corresponds to an integer value of -8 to 1, and the available frequency range of link 2 is a frequency range between n and -9 to 2; link 3 The available center frequency corresponds to an integer value of -6 to 2, the available frequency range of link 3 is n from -7 to 3; the available center frequency of link 4 corresponds to an n value of 0. For integers up to 8, the available frequency range for link 4 is a frequency range between n and -1 to 9. It can be seen that the unavailable frequency range of the link can be determined by the available center frequency of the link.
  • interface 1 and interface 6 are upper and lower wavelength interfaces, that is, interface 1 can transmit or receive one wavelength, and interface 6 can transmit or receive one wavelength.
  • the available center frequencies of the upper and lower wavelength interfaces 1 and the upper and lower wavelength interfaces 6 may be fixed or adjustable according to the adopted optical modules, and the spectrum bandwidth required for transmitting or receiving wavelengths may also be fixed or may be Tune.
  • n of the available center frequency of the upper and lower wavelength interfaces 1 is an integer from -30 to 30, and the spectrum bandwidth is 50 GHz; the available center frequency of the upper and lower wavelength interfaces 6 corresponds to n of -10 to 10 The integer between them, the spectrum bandwidth is 50GHz.
  • the path calculation and the spectrum resource allocation can be at the head node of the link or a Path Computation Element (PCE) (for example, a centralized path calculation server in the network, where the nodes in the network can request the PCE to calculate the path and Return the result)
  • PCE Path Computation Element
  • the network topology information can be obtained by using a routing protocol.
  • the first node or the PCE participates in OSPF (Open Shortest Path First) route flooding to collect information about links advertised by other nodes. Get the topology information of the network.
  • OSPF Open Shortest Path First
  • the link information from node A to node D is provided in Tables 1 to 4 below:
  • Node A to Node D use the OSPF route flooding mechanism defined by the OSPF routing protocol to advertise the link information of the respective nodes to other nodes.
  • the Link State Advertisement (LSA) carries its link information, and the OSPF route flooding mechanism is used to advertise the LSA to other nodes.
  • the LSA carries the link TLV (Type/Length/Value), and the link TLV carries at least the local/remote interface number sub-TLV, the available center frequency sub-TLV, and the available frequency range sub-TLV. One, spectrum bandwidth sub-TLV, etc.
  • the local/remote interface number sub-TLV and the available center frequency sub-TLV can be implemented by the sub-TLV defined by the existing OSPF routing protocol, and the spectrum bandwidth sub-TLV needs to be extended by the OSPF routing protocol definition.
  • the information corresponding to the spectrum bandwidth sub-TLV release may not be flooded, but when requesting the calculation path and allocating the spectrum bandwidth, this information still needs to be provided, for example, sent to the PCE by the path computation client (PCC, Path Computation Clients).
  • the spectrum bandwidth is specified in the path calculation request message.
  • Figure 9 shows an example of a spectral bandwidth sub-TLV format.
  • the node or server responsible for path calculation and spectrum resource allocation After obtaining the topology information of the network, the node or server responsible for path calculation and spectrum resource allocation saves the topology information of the network locally, and then uses it to calculate the path and allocate the spectrum resource for the path.
  • the node A obtains the link information of the node 8, the node C, and the node D by using the routing protocol, and adds the link information of the node A itself, thereby obtaining the topology information of the network, that is, the information in Tables 1 to 4. .
  • the following describes in detail how the first node A determines the path between the upper and lower wavelength interfaces and allocates spectrum resources for the determined path based on the spectral bandwidth of the upper and lower wavelength interfaces.
  • node A needs to calculate the paths from the upper and lower wavelength interfaces 1 to the upper and lower wavelength interfaces 6, and allocate spectrum resources for these paths.
  • the node A receives the wavelength connection establishment request from the upper and lower wavelength interface 1 to the upper and lower wavelength interfaces 6 and needs to establish a wavelength connection, or after the node A detects the wavelength connection failure of the upper and lower wavelength interface 1 to the upper and lower wavelength interfaces 6,
  • the node A is triggered to perform path calculation and spectrum resource allocation.
  • the specific calculation process is as follows:
  • Node A uses the Constrained Shorted Path First (CSPF) algorithm to obtain the potential path from the upper and lower wavelength interfaces 1 to the upper and lower wavelength interfaces: a) Node A searches for the link information of the potential path head node (for example, the first node) Is node A, look up the link information of Table 1.) Select an interface from Table 1, for example, interface 2, and then find that the opposite end of interface 2 is interface 3 of node B. Therefore, interface 2 acts as a potential next hop for interface 1. Save it up;
  • CSPF Constrained Shorted Path First
  • Node A continues to search for the link information advertised by the next node (for example, the link information of Table 2 issued by Node B), selects an interface, such as interface 4, and finds that the opposite end of interface 4 is interface 5 of node C, interface 4 is saved as a potential next hop for interface 2 (if interface 3 is selected, the potential path is returned to node A, a loop occurs, so interface 3 is excluded);
  • Node A continues to search for the routing information advertised by the next node (for example, the link information of Table 3 published by the node C), and finds that the upper and lower wavelength interfaces 6 belong to the node C, so that a potential path is successfully calculated, and the first path is obtained, that is, the interface. 2 to interface 3 to interface 4 to interface 5; d) Similarly, if interface 10 is selected as a potential next hop for interface 2 in step a), Then another potential path can be obtained, namely the second path, interface 10 to interface 9 to interface 8 to interface 7.
  • Node A allocates spectrum resources for the calculated two potential paths according to the spectrum bandwidths of the upper and lower wavelength interfaces 1 and the upper and lower wavelength interfaces 6:
  • the above-mentioned coincident available center frequencies are then intersected with the available center frequencies of all interfaces (links) in the path, and one of the available center frequencies from the intersection is selected as the center frequency;
  • n is the center frequency corresponding to -3;
  • n may be -5, -4,
  • Node A obtains the path from the upper and lower wavelength interfaces 1 to the upper and lower wavelength interfaces 6 and the center frequency.
  • the above path calculation and spectrum resource allocation process can also be implemented in a centralized PCE. At this time, the PCE needs to acquire the topology information of the network, and calculate the path and allocate the spectrum resources according to the above method.
  • the spectrum bandwidth of the upper and lower wavelength interfaces is variable, for example, according to the path genus
  • the spectrum bandwidth corresponding to the path attribute needs to be advertised. That is, path calculation and spectrum resource allocation need to consider the path attribute to find the available center. frequency.
  • the "path hop spectrum bandwidth sub-TLV” defined in Figure 10 can be used to publish the spectrum bandwidth corresponding to the path hop count.
  • “Render” indicates the number of bytes of the static load of this sub-TLV.
  • a 16-bit number is used to indicate the spectrum bandwidth supported by the interface, in GHz.
  • the upper and lower limits of the path hop count indicate the range of path hops to which the spectrum bandwidth applies.
  • the "Path Length Spectrum Bandwidth Sub-TLV” defined in Figure 11 can be used to publish the spectrum bandwidth corresponding to the path length.
  • a 16-bit number is used to indicate the spectral bandwidth supported by the interface, in GHz; the upper and lower limits of the path length indicate the range of path lengths for which the spectrum bandwidth is applicable.
  • the "fiber type spectrum bandwidth sub-TLV” defined in Figure 12 can be used to publish the spectrum bandwidth corresponding to different fiber types.
  • a 16-bit number is used to indicate the spectrum bandwidth supported by the interface, in GHz; the upper and lower limits of the path length indicate the type of fiber to which the spectrum bandwidth applies.
  • the spectrum bandwidth of the upper and lower wavelength interfaces 1 and the upper and lower wavelength interfaces 6 are related to the number of path hops: When the hop count is less than or equal to 5 hops, the spectrum bandwidth is 50 GHz; when the path hop count is greater than 5 hops, the spectrum bandwidth is 100 GHz. Then, node A and node C need to carry the above information by using the "path hopping spectrum bandwidth sub-TLV" defined above, and distribute it to the computing node in the network.
  • the PCE needs to participate in the flooding of the OSPF routes of the network to obtain the topology information advertised by each node.
  • the PCE After the PCE receives the path calculation and the spectrum resource allocation request, and requests to calculate the path from the upper and lower wavelength interfaces 1 to the upper and lower wavelength interfaces 6 and allocates the spectrum resources, the PCE calculates the path by using the CSPF algorithm, and searches for the available center frequency corresponding to the path.
  • the calculation of the path is similar to the previous process, so two potential paths can be obtained: the first path (interface 2 to interface 3 to interface 4 to interface 5) and the second path (interface 10 to interface 9 to interface 8 to interface 7).
  • the hop count of the first path is 3 (after 3 nodes), and the spectrum bandwidth of the upper and lower wavelength interface 1 and the upper and lower wavelength interface 6 corresponding to the hop 3 of the first path is found, and is known as 50 GHz;
  • the above-mentioned coincident available center frequencies are then intersected with the available center frequencies of all interfaces (links) in the path, and one of the available center frequencies from the intersection is selected as the center frequency;
  • Node A selects one of the above available center frequencies to assign to the first path according to a certain policy.
  • the second path has no available center frequency.
  • the path calculation means 130 includes an acquisition unit 131, a determination path unit 132, and an allocation unit 133.
  • the obtaining unit 131 is configured to acquire an interface number of the wavelength division multiplexing link in the network, an unusable frequency range of the wavelength division multiplexing link, an interface number of the first upper and lower wavelength interfaces, and an interface number of the second upper and lower wavelength interfaces, The available center frequency of the first upper and lower wavelength interfaces and the spectrum bandwidth of the first upper and lower wavelength interfaces, the available center frequency of the second upper and lower wavelength interfaces, and the spectrum bandwidth of the second upper and lower wavelength interfaces.
  • the obtaining unit 131 obtains the spectrum bandwidth of the upper and lower wavelength interfaces according to the path attribute, where the path attribute includes the path hop count, the path length, or the fiber type.
  • the determining path unit 132 is configured to determine a path between the first upper and lower wavelength interfaces and the second upper and lower wavelength interfaces based on the interface number of the wavelength division multiplexing link, the interface number of the first upper and lower wavelength interfaces, and the interface number of the second upper and lower wavelength interfaces. .
  • the allocating unit 133 is configured to use an unavailable frequency range of the wavelength division multiplexing link through which the path passes, an available center frequency of the first upper and lower wavelength interfaces, an available center frequency of the second upper and lower wavelength interfaces, a spectrum bandwidth of the first upper and lower wavelength interfaces, and The spectrum bandwidth of the second upper and lower wavelength interfaces is the path allocation center frequency.
  • the allocation unit 133 further includes a determination module 1331 and a selection module 1332, as shown in FIG. Specifically, the determining module 1331 is configured to use an unavailable frequency range of each wavelength division multiplexing link in the path, an available center frequency of the first upper and lower wavelength interfaces, an available center frequency of the second upper and lower wavelength interfaces, and a first upper and lower wavelength interfaces. The spectral bandwidth and the spectral bandwidth of the second upper and lower wavelength interfaces determine whether the path has an available center frequency. Selection module 1332 is used to select one of the available center frequencies of the path as the center frequency of the path.
  • the determining module 1331 is further configured to: select one of available center frequencies of the first upper and lower wavelength interfaces and an available center frequency of the second upper and lower wavelength interfaces; based on the selected available center frequency and the spectral bandwidth of the upper and lower wavelength interfaces Determining the frequency range of the path, wherein the spectrum bandwidth of the upper and lower wavelength interfaces is equal to the spectrum bandwidth of the first upper and lower wavelength interfaces; determining whether the frequency range of the path and the unavailable frequency range of the wavelength division multiplexing link through which the path passes; If there is no coincidence, it is determined that the available available center frequency is the available center frequency of the path.
  • the selected available center frequency is respectively subtracted from half of the frequency bandwidth of the upper and lower wavelength interfaces, and the selected available center frequency plus half of the frequency bandwidth of the upper and lower wavelength interfaces is used as the end value of the frequency range to determine the frequency of the path. range.
  • the path calculation means 150 includes an acquisition unit 151, a determination path unit 152, and an allocation unit 153.
  • the obtaining unit 151 is configured to acquire an interface number of the wavelength division multiplexing link in the network, an available center frequency of the wavelength division multiplexing link, an interface number of the first upper and lower wavelength interfaces, and an interface number of the second upper and lower wavelength interfaces.
  • the obtaining unit 151 is further configured to obtain a spectrum bandwidth of the upper and lower wavelength interfaces according to the path attribute, where the path attribute includes a path hop count, a path length, or a fiber type.
  • the determining path unit 152 is configured to determine a path between the first upper and lower wavelength interfaces and the second upper and lower wavelength interfaces based on the interface number of the wavelength division multiplexing link, the interface number of the first upper and lower wavelength interfaces, and the interface number of the second upper and lower wavelength interfaces. .
  • the allocating unit 153 is configured to use an unavailable frequency range of the wavelength division multiplexing link through which the path passes, an available center frequency of the wavelength division multiplexing link through which the path passes, an available center frequency of the first upper and lower wavelength interfaces, and a second upper and lower wavelength interface.
  • the available center frequency, the spectral bandwidth of the first upper and lower wavelength interfaces, and the spectral bandwidth of the second upper and lower wavelength interfaces allocate a center frequency for the path.
  • the allocating unit 153 is further configured to select an available center frequency of the first upper and lower wavelength interfaces and an available center frequency of the second upper and lower wavelength interfaces and an available center frequency of the available center frequency of the wavelength division multiplexed link through which the path passes One; respectively subtracting half of the selected available center frequency from the frequency bandwidth of the upper and lower wavelength interfaces, and selecting the available center frequency plus half of the frequency bandwidth of the upper and lower wavelength interfaces as the end value of the frequency range, wherein the first upper and lower wavelengths When the spectrum bandwidth of the interface is equal to the spectrum bandwidth of the second upper and lower wavelength interfaces, the spectrum bandwidth of the upper and lower wavelength interfaces is the spectrum bandwidth of the first upper and lower wavelength interfaces.
  • the spectrum bandwidth of the first upper and lower wavelength interfaces is not equal to the spectrum bandwidth of the second upper and lower wavelength interfaces.
  • the spectrum bandwidth of the upper and lower wavelength interfaces is the larger one of the spectrum bandwidth of the first upper and lower wavelength interfaces and the spectrum bandwidth of the second upper and lower wavelength interfaces; determining the frequency range and the unavailable frequency range of the wavelength division multiplexing link through which the path passes Whether there is a coincident part; if there is no weight Part, determines the selected path available center frequencies available center frequencies; available center frequencies in a selected path as the path of the center frequency.
  • the range of unavailable frequencies of the wavelength division multiplexed link through which the path passes is determined according to the available center frequency of the wavelength division multiplexed link through which the path passes.
  • the disclosed systems, devices, and methods may be implemented in other ways.
  • the device embodiments described above are merely illustrative.
  • the division of the unit is only a logical function division.
  • 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.
  • the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be electrical, mechanical or otherwise.
  • the units described as separate components may or may not be physically separate, 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 solution of the embodiment.
  • 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 functions may be stored in a computer readable storage medium if implemented in the form of a software functional unit and sold or used as a standalone product.
  • the technical solution of the present invention which is essential to the prior art or part of the technical solution, may be embodied in the form of a software product stored in a storage medium, including
  • the instructions are used to cause a computer device (which may be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention.
  • 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, which can store program codes. .

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Optical Communication System (AREA)
  • Data Exchanges In Wide-Area Networks (AREA)

Abstract

Dans ses modes de réalisation, la présente invention se rapporte à un procédé et à un dispositif de calcul de chemin. Sur la base des modes de réalisation de la présente invention, le procédé de calcul de chemin consiste : à déterminer un chemin entre une première interface de multiplexage de longueur d'onde à insertion-extraction et une seconde interface de multiplexage de longueur d'onde à insertion-extraction sur la base d'un numéro d'interface d'une liaison à multiplexage par répartition en longueur d'onde, d'un numéro d'interface de la première interface de multiplexage de longueur d'onde à insertion-extraction et d'un numéro d'interface de la seconde interface de multiplexage de longueur d'onde à insertion-extraction ; et à allouer une fréquence centrale pour le chemin sur la base d'une plage de fréquences non disponibles de la liaison à multiplexage par répartition en longueur d'onde à travers laquelle passe le chemin, d'une fréquence centrale disponible de la première interface de multiplexage de longueur d'onde à insertion-extraction, d'une fréquence centrale disponible de la seconde interface de multiplexage de longueur d'onde à insertion-extraction, d'une bande passante de spectre de la première interface de multiplexage de longueur d'onde à insertion-extraction et d'une bande passante de spectre de la seconde interface de multiplexage de longueur d'onde à insertion-extraction. La solution technique de la présente invention permet d'acquérir les données de topologie d'un réseau à grille flexible de façon automatisée, et de calculer ainsi automatiquement le chemin de la liaison et d'allouer les ressources disponibles du spectre au réseau à grille flexible.
PCT/CN2011/081024 2011-10-20 2011-10-20 Procédé et dispositif de calcul de chemin WO2012163015A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/CN2011/081024 WO2012163015A1 (fr) 2011-10-20 2011-10-20 Procédé et dispositif de calcul de chemin
CN201180002216.6A CN102439886B (zh) 2011-10-20 2011-10-20 路径计算的方法及装置

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2011/081024 WO2012163015A1 (fr) 2011-10-20 2011-10-20 Procédé et dispositif de calcul de chemin

Publications (1)

Publication Number Publication Date
WO2012163015A1 true WO2012163015A1 (fr) 2012-12-06

Family

ID=45986260

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2011/081024 WO2012163015A1 (fr) 2011-10-20 2011-10-20 Procédé et dispositif de calcul de chemin

Country Status (2)

Country Link
CN (1) CN102439886B (fr)
WO (1) WO2012163015A1 (fr)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103427929B (zh) * 2012-05-25 2017-11-10 中兴通讯股份有限公司 路径建立方法及装置
CN103457663B (zh) * 2012-06-01 2018-08-28 中兴通讯股份有限公司 路径建立方法及装置
CN103457877B (zh) 2012-06-01 2018-07-27 中兴通讯股份有限公司 路径建立方法及装置
WO2014194505A1 (fr) * 2013-06-06 2014-12-11 华为技术有限公司 Procédé, nœud et système pour établir la connexion de longueur d'onde
CN112838987A (zh) * 2019-11-25 2021-05-25 中兴通讯股份有限公司 Och业务路由确定方法、装置和存储介质

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1510851A (zh) * 2002-12-24 2004-07-07 ض� 波分复用光突发交换网络中的数据与控制调度方法和装置
US20080069123A1 (en) * 2006-09-20 2008-03-20 Fujitsu Limited Signal relay apparatus, node apparatus, network system, virtual-link generating method, path calculating method, and computer product
CN101662704A (zh) * 2008-08-26 2010-03-03 华为技术有限公司 获取光波长路径的方法、系统和节点设备
CN101820556A (zh) * 2009-02-26 2010-09-01 华为技术有限公司 路由协议消息发布和路由计算的方法、装置和系统

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102857837B (zh) * 2011-06-30 2017-11-07 中兴通讯股份有限公司 灵活栅格光网络的波长标签编码方法、处理方法及节点

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1510851A (zh) * 2002-12-24 2004-07-07 ض� 波分复用光突发交换网络中的数据与控制调度方法和装置
US20080069123A1 (en) * 2006-09-20 2008-03-20 Fujitsu Limited Signal relay apparatus, node apparatus, network system, virtual-link generating method, path calculating method, and computer product
CN101662704A (zh) * 2008-08-26 2010-03-03 华为技术有限公司 获取光波长路径的方法、系统和节点设备
CN101820556A (zh) * 2009-02-26 2010-09-01 华为技术有限公司 路由协议消息发布和路由计算的方法、装置和系统

Also Published As

Publication number Publication date
CN102439886A (zh) 2012-05-02
CN102439886B (zh) 2014-07-09

Similar Documents

Publication Publication Date Title
Patel et al. Survivable transparent flexible optical WDM (FWDM) networks
US9621969B2 (en) Management and control of software defined networking enabled open transport networks
US9621968B2 (en) Multi layer, multi vendor, multi domain, applications for software defined networking enabled networks
Patel et al. Routing, wavelength assignment, and spectrum allocation algorithms in transparent flexible optical WDM networks
Casellas et al. Design and experimental validation of a GMPLS/PCE control plane for elastic CO-OFDM optical networks
US9338529B2 (en) Routing and bandwidth assignment for flexible grid wavelength switched optical networks
Agrawal et al. Spectrum efficient distance-adaptive paths for fixed and fixed-alternate routing in elastic optical networks
JP2016511576A (ja) 光波長分割多重化（ｗｄｍ）ネットワークにおけるネットワークフラグメンテーション測定
JP2019201429A (ja) ネットワーク管理装置、物理ネットワーク管理装置、およびパス設定方法
Muñoz et al. Dynamic distributed spectrum allocation in GMPLS-controlled elastic optical networks
Casellas et al. An integrated stateful PCE/OpenFlow controller for the control and management of flexi-grid optical networks
WO2012163015A1 (fr) Procédé et dispositif de calcul de chemin
WO2013000328A1 (fr) Procédé de codage d'étiquettes de longueur d'onde, procédé de traitement et nœud pour réseau optique à grille souple
WO2018050093A1 (fr) Procédé et appareil permettant une utilisation de réseau efficace à l'aide de super-canaux
Martínez et al. Experimental evaluation of an on-line RSA algorithm for SDN-controlled optical metro networks with VCSEL-based S-BVTs
US10778562B2 (en) Path computation in a multi-tenant network
Ji et al. Optical layer traffic grooming in flexible optical WDM (FWDM) networks
Chen et al. Hybrid switching and p-routing for optical burst switching networks
WO2015182070A1 (fr) Dispositif de gestion de réseau optique, et procédé de gestion de réseau optique
JP5759636B2 (ja) 光ネットワークにおいて帯域幅を割り当てる方法
Muñoz et al. Control plane solutions for dynamic and adaptive flexi-grid optical networks
WO2013178005A1 (fr) Procédé et appareil de paramétrage de chemins
Casellas et al. IDEALIST control plane architecture for multi-domain flexi-grid optical networks
WO2013178006A1 (fr) Procédé d'établissement de chemins et dispositif associé
WO2015033545A1 (fr) Appareil de commande de réseau optique et procédé de commande de réseau optique

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 201180002216.6

Country of ref document: CN

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11866467

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11866467

Country of ref document: EP

Kind code of ref document: A1