WO2018072728A1 - 段标识sid获取 - Google Patents

段标识sid获取 Download PDF

Info

Publication number
WO2018072728A1
WO2018072728A1 PCT/CN2017/106853 CN2017106853W WO2018072728A1 WO 2018072728 A1 WO2018072728 A1 WO 2018072728A1 CN 2017106853 W CN2017106853 W CN 2017106853W WO 2018072728 A1 WO2018072728 A1 WO 2018072728A1
Authority
WO
WIPO (PCT)
Prior art keywords
label
forwarding
forwarding node
prefix
node
Prior art date
Application number
PCT/CN2017/106853
Other languages
English (en)
French (fr)
Inventor
叶金荣
Original Assignee
新华三技术有限公司
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 新华三技术有限公司 filed Critical 新华三技术有限公司
Publication of WO2018072728A1 publication Critical patent/WO2018072728A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/02—Topology update or discovery
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/50—Routing or path finding of packets in data switching networks using label swapping, e.g. multi-protocol label switch [MPLS]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/64—Routing or path finding of packets in data switching networks using an overlay routing layer
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/74—Address processing for routing
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/74—Address processing for routing
    • H04L45/745—Address table lookup; Address filtering
    • H04L45/748—Address table lookup; Address filtering using longest matching prefix

Definitions

  • a segment routing (SR) adopts a source path selection mechanism, and may encapsulate a segment identifier (SID) of all segments associated with the path in the packet in the source node.
  • SID segment identifier
  • the forwarding node forwards the packet according to the SID of the packet.
  • SID advertisement and interaction within the IGP domain can be implemented through the extended Interior Gateway Protocol (IGP).
  • IGP Interior Gateway Protocol
  • this method may require that each forwarding node in the network runs an extended IGP to implement SID notification, which is complicated to implement.
  • FIG. 1 is a schematic diagram of a method for acquiring an SID according to an embodiment of the present disclosure
  • FIG. 2 is a schematic diagram of a system architecture of an SID acquisition method application according to an embodiment of the present disclosure
  • FIG 3 is an interaction process diagram of an SID acquisition method according to an embodiment of the present disclosure.
  • FIG. 5 is a schematic structural diagram of an SDN controller according to an embodiment of the present disclosure.
  • FIG. 6 is another schematic structural diagram of an SDN controller according to an embodiment of the present disclosure.
  • FIG. 7 is a schematic structural diagram of a forwarding node according to an embodiment of the present disclosure.
  • FIG. 8 is another schematic structural diagram of a forwarding node according to an embodiment of the present disclosure.
  • first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other.
  • first information may also be referred to as second information without departing from the scope of the present disclosure.
  • second information may also be referred to as first information.
  • word "if” as used herein may be interpreted as "when” or “when” or “in response to a determination.”
  • a “forwarding node” may refer to a network device, such as a “network element”, which may be a router, a switch, an optical transport network (OTN) device, a packet transport network (PTN) device, or a wave.
  • SR is a routing and forwarding protocol promoted by the Internet Engineering Task Force (IETF).
  • the SR defines the following two types of segments: adjacency segment (abbreviated as adjacency segment) and a prefix/node segment (prefix/Node segment, which may be simply referred to as a prefix segment or a node segment).
  • the adjacent segment indicates a one-hop path from the current node to its neighbor node.
  • the prefix segment indicates the one-hop or multi-hop shortest path of the current node to the associated node in the network. For example, the packet is forwarded according to the path of the node A ⁇ the node C ⁇ the node O ⁇ the node Z, where the node C and the node O are in a neighbor relationship.
  • the path contains three segments: a prefix segment from node A to node C, a contiguous segment from node C to node O, and a prefix segment from node O to node Z.
  • the SR uses a label to guide packet forwarding.
  • the tags can also be divided into adjacent tags and prefix tags (or node tags).
  • the labels of the three segments included in the path are sequentially pushed into the label stack of the packet, that is, the prefix of the prefix segment from node O to node Z is sequentially pressed.
  • Label, node C to node O the adjacent label of the adjacent segment and the prefix label of the prefix segment from node A to node C.
  • the head node A can query the label forwarding entry according to the prefix label of the last pushed node A to the segment of the node C. According to the result of the lookup table, it is decided whether the prefix label is popped up, or whether the prefix label is replaced with the outgoing label corresponding to the entry.
  • Label block which reserves labels for consecutive segments of value.
  • the minimum value of the range of the reserved tag may also be referred to as a "base value.”
  • Each forwarding node may reserve one label block for the adjacent label and the prefix label, that is, the SR Local Block (SRLB) and the SR Global Block (SRGB).
  • the two label blocks can be consecutive segments, such as SRLB [16,999], SRGB [1000, 1999], or SRLB and SRGB can be independent two segments, such as SRLB is [16,999], SRGB is [5000, 5999].
  • the range of SRLB and SRGB reserved by different forwarding nodes may be the same or different.
  • a label forwarding entry that is, a Multi-Protocol Label Switching (MPLS)-based forwarding entry, generally includes a next hop address, a label operation, and the like.
  • the tag operation includes a pop tag, a push tag, a swap tag, and the like.
  • the outer label in the labeled message can be replaced with the outgoing label specified by the label forwarding entry, and then the next hop specified by the label forwarding entry is forwarded.
  • the address forwards the tagged message.
  • IP prefix The IP address segment can be represented by the following two methods: one is the network address and mask representation, such as 10.1.1.0 255.255.255; the other is the network address/mask length representation. For example, 10.1.1.0/24, where the IP prefix refers to an IP address segment expressed in the latter way.
  • a forwarding node can have multiple IP prefixes. For example, a forwarding node has three local loopback interfaces. Each loopback interface has its own IP address. For example, the IP address of the loopback 0 interface is 10.1.1.1/32, and the IP address of the loopback 1 interface is 20.1. .1.1/24, the IP address of the loopback 2 interface is 30.1.1.1/32, then there are 3 IP prefixes on the forwarding node, which are 10.1.1.1/32, 20.1.1.1/24, 30.1.1.1/32.
  • the embodiment of the present disclosure provides a SID acquisition method and device, and implements SID allocation and advertisement through a Software Defined Networking (SDN) controller.
  • SDN Software Defined Networking
  • the SR protocol only needs to be run on the SDN controller, and the SR protocol does not need to be run on each forwarding node, so that the advantages of centralized control of the SDN controller can be fully utilized, and the implementation is relatively simple.
  • the SID obtaining method may include the following steps:
  • step S101 the SDN controller collects a network topology
  • step S102 the SDN controller acquires a label block of each forwarding node in the network topology
  • step S103 the SDN controller allocates a corresponding SID to each forwarding node according to the network topology and the label block of each forwarding node;
  • step S104 the SDN controller sends the allocated SID to the corresponding forwarding node.
  • the SID obtaining method provided by the embodiment of the present disclosure is applicable to the system shown in FIG. 2, and the system includes an SDN controller 100 and multiple forwarding nodes, such as routers (R) 201, R 202, R 203, R 204, and R. 205.
  • routers (R) 201, R 202, R 203, R 204, and R. 205 are forwarding nodes, such as routers (R) 201, R 202, R 203, R 204, and R. 205.
  • the SDN controller 100 is configured to allocate a SID to the forwarding node in the network domain according to the network topology and the label block of the forwarding node, and allocate an adjacency label to the IP address of the adjacent interface (Internet Protocol) of each forwarding node.
  • Each forwarding node's IP prefix is assigned a prefix tag; and the assigned SID is sent to the corresponding forwarding node.
  • the forwarding node is configured to forward the message, and the SID delivered by the SDN controller 100 can be received and maintained in the embodiment of the disclosure.
  • each forwarding node may not run the SR protocol, that is, the forwarding node does not perform SID allocation and notification, directly receives the SID sent by the SDN controller 100, and then activates the label forwarding entry stored on the local node according to the received SID. The packet is forwarded according to the activated label forwarding entry.
  • FIG. 3 is a schematic diagram of an interaction process of an SID acquisition method according to an embodiment of the present disclosure, including the following steps.
  • Step 301 The SDN controller 100 collects the network topology.
  • the SDN controller 100 can collect the network topology through a topology collection mechanism.
  • the Border State Protocol (BGP) packet can be used to collect the link state information of the network domain from the forwarding node that supports BGP in the network domain, and then calculate the link state information based on the collected link state information.
  • the link state information returned by the forwarding node to the SDN controller 100 may be carried in a BGP update message.
  • the network topology may include information about: forwarding nodes in the network domain, IP prefixes on the forwarding nodes, subnets to which the forwarding nodes are connected, links between forwarding nodes, and interface addresses of forwarding nodes at both ends of the link Wait.
  • Step 302 The SDN controller 100 acquires a label block of each forwarding node in the network topology.
  • the SDN controller 100 can send a request to each forwarding node in the network topology through a network configuration (Netconf) interface, and then receive a response returned by each forwarding node in the network topology, and the response returned by the forwarding node carries the label block of the forwarding node.
  • the label block returned by each forwarding node includes SRLB and SRGB of each forwarding node.
  • the SDN controller 100 can also obtain the label block of each forwarding node by other means, such as through a Simple Network Management Protocol (SNMP).
  • SNMP Simple Network Management Protocol
  • Step 303 The SDN controller 100 allocates a corresponding SID to each forwarding node according to the network topology and the label block of each forwarding node.
  • the SID allocated by the SDN controller 100 mainly includes an adjacency tag and a prefix tag.
  • the following takes the first forwarding node on the path as an example to describe how the SDN controller 100 allocates the adjacency tag and the prefix tag to the forwarding node, and the remaining forwarding nodes can process according to the first forwarding node.
  • the IP address of the adjacency interface connected to the first forwarding node (hereinafter referred to as "adjacent interface IP address") is determined according to the network topology obtained in step 301.
  • the neighboring interface is located on a neighboring node of the first forwarding node.
  • the first forwarding node is R 201 in FIG. 2
  • the IP address of the interface connected to R 201 on R 202 is A2, R.
  • the IP address of the interface connected to R 201 on 203 is A3, and the IP address of the adjacent interface of R 201 includes A2 and A3.
  • adjacency labels are allocated for each adjacency interface IP address of the determined first forwarding node. Different adjacent interface IP addresses are assigned different adjacent labels, and the allocated adjacent labels are in the range defined by the SRLB of the first forwarding node. For example, if the SRLB of R 201 in FIG. 2 is [16,999], then in [16,999], different adjacencies may be assigned to the adjacent interface IP addresses A2 and A3 of R 201, such as assigning adjacency to A2. Tag 16, assigning adjacency tag 17 to A3.
  • an index value is assigned to each IP prefix of the first forwarding node, and the index value is globally unique within the network domain.
  • the index value has a one-to-one correspondence with the IP prefix.
  • the prefix label of the IP prefix on each forwarding node is determined according to the index value assigned by the IP prefix and the SRGB of each forwarding node.
  • the SDN controller 100 may determine a prefix label of the IP prefix on each forwarding node based on a base value of each SRGB of each forwarding node and an index value of the IP prefix. For example, when determining the prefix label of the first forwarding node of the first forwarding node on the second forwarding node, the base value of the SRGB of the second forwarding node may be added to the index value of the first IP prefix, and the obtained sum will be obtained. As the prefix label of the first IP prefix on the second forwarding node, the obtained prefix label should fall within the range defined by the SRGB of the second forwarding node.
  • Step 304 The SDN controller 100 sends the allocated SID to the corresponding forwarding node.
  • the SDN controller 100 can deliver the allocated SID to the corresponding forwarding node through the Netconf interface.
  • the SID includes an adjacency tag and a prefix tag.
  • the "correspondence" relationship between the SID and the forwarding node can be understood as: the IP address of the adjacency interface of the first forwarding node.
  • the allocated adjacency tag may be sent to the first forwarding node; the prefix tag of the first IP prefix allocated to the first IP prefix of the first forwarding node on the second forwarding node may be sent to the second forwarding node.
  • the second forwarding node herein may include one or more forwarding nodes other than the first forwarding node. For example, Table 1 below can be sent only to R1, and Table 2 below can be sent only to R2, which can reduce the burden on the node and save bandwidth.
  • the SDN controller 100 may generate first forwarding information based on the allocated adjacent label, where the first forwarding information includes a neighboring label and a next hop address corresponding to the adjacent label; and the SDN controller 100 may be based on the allocated prefix.
  • the tag generates second forwarding information, where the second forwarding information includes a prefix label and a next hop address and an outgoing label corresponding to the prefix label.
  • the SDN controller 100 can transmit the first forwarding information and the second forwarding information to the corresponding forwarding node.
  • the SDN controller 100 can send the next hop address associated with the contiguous label to the R 201, as shown in Table 1.
  • the SDN controller 100 can set the next hop address associated with the prefix label and the outgoing label. It is sent to R 202 together, as shown in Table 2.
  • each forwarding node may pre-arrange with the SDN controller 100 to receive the adjacency tag through the API 0 and receive the prefix tag through the API 1.
  • APIs application programming interfaces
  • Tables 1 and 2 above show examples of tag forwarding entries, respectively.
  • the label forwarding entry records the correspondence between the adjacent label and the next hop address.
  • the label forwarding entry records the correspondence between the prefix label and the outgoing label to the next hop address and the next hop address.
  • Table 1 and Table 2 are not restrictive, and the contents of the label forwarding entry can be expanded as needed.
  • Step 305 The forwarding node activates the label forwarding entry stored on the local node according to the received SID.
  • the label forwarding entry may be generated by the forwarding node in advance, or may be generated by the SDN controller 100 and sent to the forwarding node.
  • the forwarding node or SDN controller 100 may generate a label forwarding entry for each forwarding path in the network topology according to the adjacency label, the prefix label, and the associated next hop address, outgoing label, and the like as shown in Table 1 and Table 2 above.
  • the forwarding node may directly activate the label forwarding entry whose received adjacent label is an incoming label.
  • the forwarding node may activate the label forwarding entry whose label is the received prefix label and the outgoing label is not empty, and the label forwarding entry whose activation label is the received prefix label and the outgoing label is empty.
  • the forwarding node may directly activate the label forwarding entry; if the incoming label is a prefix label and the outgoing label is not empty If there are multiple label forwarding entries, the forwarding node may activate only one or more label forwarding entries with the optimal route.
  • the entry management module or the proxy module of the forwarding node can implement activation of the label forwarding entry by installing the label forwarding entry to the software layer or the hardware layer of the node itself.
  • the optimal route mentioned here may be the shortest path route, or may refer to the best matching route matched according to other principles. Taking the optimal route as the shortest path route as an example, only the label forwarding entry corresponding to the optimal route can be activated, so that the packet is always forwarded by the shortest path, thereby improving the packet transmission efficiency.
  • Step 306 The forwarding node processes the packet matching the activated label forwarding entry.
  • the forwarding node can match the label carried in the packet with the label forwarding entry. If the label carried in the packet matches the inbound label of a label forwarding entry, the POP (remove top label) operation or SWAP (switch label) is performed on the label stack of the packet according to the label operation indicated by the matching entry. Operation and forwarding the message to the next hop address indicated by the matching entry.
  • POP move top label
  • SWAP switch label
  • each device has a loopback 0 interface.
  • Router A has an additional loopback 1 interface.
  • Set the router ID (router ID) of the device to the IP address of the loopback 0 interface.
  • the contiguous label corresponding to the IP address of the neighboring interface of each device and the IP address corresponding to the IP address/subnet mask length of a loopback interface on the device are used as an example to describe the adjacent label and the prefix label.
  • Table 3 shows the pre-configuration information of each forwarding node.
  • the controller 400 collects the link state information of the network domain and calculates the network topology.
  • the obtained network topology can be as shown in Table 4.
  • the controller 400 acquires two types of SR tag blocks of the forwarding node from the forwarding nodes through the Netconf interface: SRLB and SRGB.
  • the obtained SR tag block can be as shown in Table 5.
  • the controller 400 allocates a globally unique Index to the IP prefix on the forwarding node in the network topology shown in Table 4. Index can be considered as an offset value relative to the SRGB base value, which can be incremented by 1 from 0. Table 6 shows the correspondence between an IP prefix and Index recorded by the controller 400.
  • the controller 400 can maintain the correspondence between the IP prefix and the index, so that the controller 400 can maintain the same label forwarding entry before and after the fault, and ensure the normal forwarding of the packet. .
  • each IP prefix is assigned a globally unique index. For example, Router A has two IP prefixes, and the two IP prefixes correspond to an Index.
  • the controller 400 allocates a prefix label on each forwarding node for each IP prefix according to the network topology, the index value of each IP prefix, and the SRGB label block of each forwarding node, and the label value is the base value of the SRGB of the forwarding node. Add the sum of the index values of the IP prefix.
  • Table 7-1 shows the prefix and outgoing labels on the forwarding prefix for the IP prefix 5.5.5.5/32 (the assigned Index is 0) on Router A.
  • Table 7-2 shows the IP prefix of 6.6.6.6/32 (the assigned Index is 2) on Router C.
  • the embodiment of the present disclosure only lists the prefix labels of the two IP prefixes on the forwarding nodes, and the prefix labels of the remaining IP prefixes on the forwarding nodes may be analogized, and are not listed one by one.
  • the outgoing label of the next hop mentioned in Table 7-1 and Table 7-2 is the prefix label of the IP prefix on the next hop node.
  • the node A wants to forward the packet to the neighboring node B, the node A queries the local label forwarding entry according to the label carried in the packet to find the matching outgoing label of the arriving node B. Then, the node A swaps the label carried by the packet to the outgoing label of the node B, and forwards the label to the next hop node B.
  • the outgoing label of the packet at the node A corresponds to the incoming label of the packet at the node B, and the node B also performs label switching, and the outgoing label of the next hop node C is marked for the packet.
  • Table 7-1 and Table 7-2 show that a certain prefix label corresponds to multiple outgoing labels, that is, a certain prefix label corresponds to multiple label forwarding entries.
  • the forwarding node may be based on The configured optimal route determines which tag forwarding entry is activated.
  • the IP prefix 5.5.5.5/32 has a prefix label of 5000 on Router A (Router ID 5.5.5.5) and an IP prefix of 5.5.5.5/32 on Router C (Router ID 6.6.6.6).
  • the prefix label on the ) is 6000.
  • the outgoing label corresponding to the prefix label 6000 has two items: an outgoing label 5000 and an outgoing label 8000.
  • Router C can learn that the path of Router A is better than that of Router D. Therefore, only the label forwarding entries corresponding to the inbound label 6000 and the outgoing label 5000 are activated. As shown in Figure 4, if the packet received by Router C has the prefix label 6000, Router C can know the packet to be reached or the IP prefix 5.5.5.5/32. That is, Router A replaces the label 6000 originally carried by the packet with the label 5000, and then forwards it to the next hop Router A.
  • the controller 400 allocates adjacency labels to each adjacent interface IP address of each forwarding node according to the network topology and the SRLB label block of each forwarding node, and the allocated adjacent labels are as shown in Table 8.
  • the SDN controller 400 sends the assigned adjacent label and the next hop address associated with the adjacent label, the assigned prefix label and the associated next hop address and outgoing label, and are sent to the corresponding forwarding through the Netconf interface. node.
  • Adjacency labels and prefix labels and related information can be sent only to the corresponding node.
  • the adjacent label included in each row in Table 8 and the corresponding next hop address may be sent only to the node corresponding to the first column Router ID of the row.
  • the information such as the adjacency label assigned to Router E (Router ID 9.9.9.9) can be sent only to Router E.
  • the adjacency label sent to Router E and the corresponding next hop address can be as follows: 9 is shown.
  • the prefix label included in each row in Table 7-1 and Table 7-2 and the corresponding next hop address and outgoing label may be sent only to the node corresponding to the first column Router ID of the row.
  • the prefix label of the IP prefix 5.5.5.5/32 on Router A (Router ID 5.5.5.5) can be sent only to Router A and sent to Router A.
  • the prefix label and the corresponding next hop address and outgoing label can be as shown in Table 10 below.
  • the information such as the prefix label of the IP address 5.5.5.5/32 on Router C (Router ID 6.6.6.6) can be sent only to Router C.
  • the corresponding prefix label and corresponding next hop address and outgoing label can be as shown in Table 11 below. Show.
  • the forwarding node After receiving the information such as the adjacent label and the prefix label, the forwarding node obtains the label forwarding entry of the local node and activates the label forwarding entry.
  • the forwarding node may directly activate all the label forwarding entries of the adjacent label that are received into the label; and activate the label forwarding entry whose inbound label is the received prefix label and the outgoing label is not empty; and, activate the entry.
  • the label is the label forwarding entry of the received prefix label and the outgoing label is null (ie, Null).
  • the forwarding node can directly activate the label forwarding entry; if the incoming label is a prefix label and the outgoing label is not empty, the label forwarding table If there are multiple items, the forwarding node can activate only one or more tag forwarding entries with the best route.
  • the above table 11 includes two next hop addresses, indicating that the packet is forwarded from Router C to the forwarding node RouterA where the IP prefix 5.5.5.5/32 is located. After the packet is forwarded to Router A, the packet may be terminated. You need to continue forwarding. You can have two forwarding paths. However, since the optimal route of the IP prefix 5.5.5.5/32 on Router C has only one next hop 56.1.1.5, Router C can activate only the first row of Table 11. That is, only the label/next hop is activated: 5000/56.1.1.5. That is to say, for the IP address 5.5.5.5, the active label forwarding entry of Router C has only the label forwarding entry with the label/next hop of 5000/56.1.1.5.
  • the SDN controller can send path information to the head node of the path.
  • the path information is a sequence of labels. Each label in the label sequence represents each segment associated with the path. For example, one in Figure 4 goes from Router E to Router.
  • the path of A can be associated with the following two segments: the contiguous segment from Router E to Router D, and the prefix segment from Router D to Router A.
  • the SDN controller can find the neighboring segment from Router E to Router D according to the ID of Router E (9.9.9.9) and the interface between Router E and Router D (89.1.1.9-89.1.1.8).
  • Adjacency label is 17;
  • the SDN controller can find that the IP prefix 5.5.5.5/32 on Router A has a prefix label of 8000 on Router D (ID 8.8.8.8), that is, Router D to Router A.
  • the prefix label of the prefix segment is 8000.
  • the SDN controller then sends the label sequence [17, 8000] representing the two segments to the head node Router E of the SR path to complete the establishment of the forwarding path.
  • the forwarding node processes the tagged packet according to the activated label forwarding entry.
  • Router E wants to forward a packet through the path established in the example in step 8 above, it should be noted that the packet may be terminated when it arrives at Router A, or it may be forwarded after Router A.
  • the packet is imported into the path and the label sequence [17, 8000] is encapsulated into the label field of the packet by first setting the static route or PBR (Policy Based Routing). Press the label 17) again. Then, the label forwarding entry is queried according to the outer label 17 of the packet, and the label 17 encapsulated in the packet is popped according to the query result, and then the packet is sent to the next hop Router D.
  • Router D receives the packet and matches the outer label of the packet to 8000.
  • the label 8000 carried in the packet can be replaced by the label 6000, and then the packet is forwarded to the next.
  • Router C, or Router D can replace the label 8000 carried in the packet with the label 7000, and then forward the packet to the next hop Router B.
  • Subsequent nodes process the packet similarly, and are not described here.
  • Router A matches the outer label of the packet to 5000. After the label forwarding entry is found, the label 5000 is displayed. Then Router A then encapsulates the packet according to the IP encapsulation or other type of encapsulation. Process it.
  • Router A terminates the forwarding of the packet. If the destination IP address of the packet is not the IP address of Router A, Router A can forward the packet in combination with the routing forwarding table.
  • the technical solution provided by the present disclosure implements SID allocation and advertisement through an SDN controller, which only needs to run the SR protocol on the SDN controller, so that the advantages of centralized control of the SDN controller can be fully utilized.
  • the implementation is relatively simple.
  • the SDN controller includes a collection module 501, an acquisition module 502, an allocation module 503, and a transmission module 504.
  • the collecting module 501 is configured to collect a network topology.
  • the obtaining module 502 is configured to obtain a label block of each forwarding node in the network topology.
  • the allocating module 503 is configured to allocate a corresponding SID to each forwarding node according to the network topology and the label block of each forwarding node.
  • the sending module 504 is configured to send the allocated SID to the corresponding forwarding node.
  • the obtaining module 502 may be specifically configured to: send a request to each forwarding node in the network topology through the Netconf interface, and receive a response returned by each forwarding node in the network topology, where the response returned by the forwarding node carries the label block of the forwarding node.
  • the allocating module 503 is specifically configured to: determine, according to the network topology, an IP address of a neighboring interface connected to each forwarding node, where the adjacency interface is on a neighboring node of the forwarding node.
  • Adjacency tags are assigned to each adjacency interface IP address, wherein different adjacency interface IP addresses of each forwarding node connection are assigned different adjacency tags, and the assigned adjacency tags are in the range of the SRLB of each forwarding node.
  • the allocation module 503 is specifically configured to: allocate an index value for an IP prefix of each forwarding node; determine an index value allocated according to each IP prefix and SRGB of each forwarding node, The prefix label of each IP prefix on each forwarding node.
  • the sending module 504 when the allocated SID is sent to the corresponding forwarding node, the sending module 504 is specifically configured to: send the allocated adjacent label to the corresponding forwarding node, so that the adjacent label and the label forwarding table are The tag forwarding entry is activated when an entry label of the entry is matched, wherein the adjacency tag is a tag allocated for an internet protocol IP address of a neighboring interface to which the corresponding forwarding node is connected;
  • the allocating module 503 is further configured to: generate first forwarding information based on the allocated neighboring label, where the first forwarding information includes an adjacency label and a next hop address corresponding to the adjacent label;
  • the tag generates second forwarding information, where the second forwarding information includes a prefix label and a next hop address corresponding to the prefix label and an outgoing label of the label forwarding entry.
  • the sending module 504 is specifically configured to: send the first forwarding information and the second forwarding information to the corresponding forwarding node respectively.
  • the division of the unit in the embodiment of the present disclosure is schematic, and only one logical function is divided, and the actual implementation may have another division manner.
  • the functional units in the embodiments of the present disclosure 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 present disclosure further provides an SDN controller.
  • the SDN controller includes a communication interface 601, a processor 602, a storage medium 603, and a bus 604; wherein, the communication interface 601, processing The 602 and the memory 603 complete communication with each other via the bus 604.
  • the communication interface 501 is configured to communicate with a network element, such as with a forwarding node.
  • Processor 502 can be a central processing unit CPU.
  • Storage medium 603 can be any electronic, magnetic, optical, or other physical storage device that can contain or store information such as executable instructions, data, and so forth.
  • the storage medium may be: RAM (Radom Access Memory), volatile storage medium, non-volatile storage medium, flash memory, storage drive (such as a hard disk drive), solid state drive, any type of storage disk.
  • the storage medium 603 stores logic instructions, and the processor 602 can execute the SID acquisition logic instructions stored in the storage medium 603 to implement the functions of the SDN controller in the SID acquisition method. See the flow shown in FIG. 3.
  • processor 602 when processor 602 reads and executes logic instructions in storage medium 603, the processor 602 is caused to perform the following operations:
  • the assigned SID is sent to the corresponding forwarding node.
  • the processor 602 when acquiring the label block of each forwarding node in the network topology, the processor 602 is further caused to:
  • the processor 602 is further caused to:
  • Assigning adjacency tags to the IP addresses of the adjacency interfaces wherein IP addresses of different adjacency interfaces connected by each of the forwarding nodes are assigned different adjacent tags, and the assigned adjacency tags are located at each of the forwarding nodes In the range of the SRLB included in the label block.
  • the processor 602 is further caused to: when the corresponding SID is assigned to each forwarding node according to the network topology and the label block of each forwarding node:
  • a prefix label of each IP prefix on each forwarding node is determined according to an index value assigned to each IP prefix and SRGB included in the label block of each forwarding node.
  • the SID includes an adjacency tag and a prefix tag.
  • the processor 602 when the allocated adjacent label is sent to the corresponding forwarding node, the processor 602 is further caused to:
  • first forwarding information based on the allocated adjacent label, where the first forwarding information includes an adjacent label and a next hop address corresponding to the adjacent label;
  • the processor 502 when the allocated prefix label is sent to the corresponding forwarding node, the processor 502 is further caused to:
  • Second forwarding information based on the allocated prefix label, where the second forwarding information includes a prefix label and a next hop address corresponding to the prefix label and an outgoing label of the label forwarding entry;
  • the embodiment of the present disclosure provides a forwarding node that is applicable to the foregoing method.
  • the forwarding node includes a receiving module 701, an activation module 702, and a processing module 703.
  • the receiving module 701 is configured to receive a SID delivered by the SDN controller, where the SID is allocated by the SDN controller.
  • the activation module 702 is configured to activate the label forwarding entry on the local node according to the received SID.
  • the processing module 703 is configured to process the packet matching the activated label forwarding entry.
  • the received SID includes a contiguous label assigned to the IP address of the contiguous interface connected to the node and a prefix label of the IP prefix of each forwarding node on the local node; the activation module 702 is specifically configured to: activate the ingress label as the A label forwarding entry of the adjacent label; the label forwarding entry whose activation label is the prefix label.
  • the division of the unit in the embodiment of the present disclosure is schematic, and only one logical function is divided, and the actual implementation may have another division manner.
  • the functional units in the embodiments of the present disclosure 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 embodiment of the present disclosure further provides a forwarding node.
  • the forwarding node includes a communication interface 801, a processor 802, a storage medium 803, and a bus 804; wherein, the communication interface 801, processing The 802 and the storage medium 803 complete communication with each other via the bus 804.
  • the communication interface 801 is configured to communicate with a network element, such as with an SDN controller.
  • Processor 802 can be a central processing unit CPU.
  • Memory 803 can be any electronic, magnetic, optical, or other physical storage device that can contain or store information such as executable instructions, data, and the like.
  • the storage medium may be: RAM (Radom Access Memory), volatile storage medium, non-volatile storage medium, flash memory, storage drive (such as a hard disk drive), solid state drive, any type of storage disk.
  • the storage medium 803 stores the logic instruction, and the processor 802 can execute the SID acquisition logic instruction stored in the storage medium 803 to implement the function of the forwarding node in the SID acquisition method. See the flow shown in FIG. 3.
  • processor 802 when processor 802 reads and executes logic instructions in storage medium 803, the processor 802 is caused to perform the following operations:
  • the packet matching the activated label forwarding entry is processed.
  • the device embodiment since it basically corresponds to the method embodiment, reference may be made to the partial description of the method embodiment.
  • the device embodiments described above are merely illustrative, wherein 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, ie may be located A place, or it can be distributed to multiple network units. Can be selected according to actual needs Some or all of the modules are used to achieve the objectives of the disclosed embodiments. Those of ordinary skill in the art can understand and implement without any creative effort.

Abstract

本公开提供一种SID获取方法和SDN控制器，该方法为：收集网络拓扑；获取所述网络拓扑中各转发节点的标签块；根据所述网络拓扑和各转发节点的标签块，为各转发节点分配SID；将分配好的SID发送给对应的转发节点。

Description

段标识SID获取
相关申请的交叉引用
本公开要求于2016年10月20日提交的、申请号为201610915623.0、发明名称为“一种SID获取方法和装置”的中国专利申请的优先权，该申请的全文以引用的方式并入本文中。
背景技术
段路由(segment routing,SR)采用源路径选择机制，可以预先在源节点将路径关联的所有段的段标识(segment identifier,SID)封装在报文中。当报文经过诸如SR节点的转发节点时，转发节点根据报文的SID对报文进行转发。通过SR指定路径转发功能，可以便捷地实现网络的负载均衡和流量工程，以及快速重路由等复杂网络功能。
可以通过扩展的内部网关协议(Interior Gateway Protocol，IGP)实现IGP域内的SID通告和交互。但这种方式可能需要网络中的每个转发节点都运行扩展的IGP以实现SID的通告，实现上比较复杂。
附图说明
图1是本公开实施例提供的一种SID获取方法的示意图；
图2是本公开实施例提供的一种SID获取方法应用的系统架构的示意图；
图3是本公开实施例提供的一种SID获取方法的交互过程图；
图4是本公开一实施例的示意图；
图5为本公开实施例提供的一种SDN控制器的结构示意图；
图6为本公开实施例提供的一种SDN控制器的另一结构示意图；
图7为本公开实施例提供的一种转发节点的结构示意图；
图8为本公开实施例提供的一种转发节点的另一结构示意图。
具体实施方式
这里将详细地对示例性实施例进行说明，其示例表示在附图中。下面的描述涉及附图时，除非另有表示，不同附图中的相同数字表示相同或相似的要素。以下示例性实施例中所描述的实施方式并不代表与本公开相一致的所有实施方式。相反，它们仅是与如所附权利要求书中所详述的、本公开的一些方面相一致的装置和方法的例子。
在本公开使用的术语是仅仅出于描述特定实施例的目的，而非旨在限制本公开。在本公开和所附权利要求书中所使用的单数形式的“一种”、“所述”和“该”也旨在包括多数形式，除非上下文清楚地表示其他含义。还应当理解，本文中使用的术语“和/或”是指并包含一个或多个相关联的列出项目的任何或所有可能组合。
应当理解，尽管在本公开可能采用术语第一、第二、第三等来描述各种信息，但这些信息不应限于这些术语。这些术语仅用来将同一类型的信息彼此区分开。例如，在不脱离本公开范围的情况下，第一信息也可以被称为第二信息，类似地，第二信息也可以被称为第一信息。取决于语境，如在此所使用的词语“如果”可以被解释成为“在……时”或“当……时”或“响应于确定”。
以下，对本公开中的部分用语进行解释说明。
本公开中，“转发节点”可以指网络设备，比如“网元”，可以是路由器、交换机、光传送网(optical transport network，OTN)设备、分组传送网(packet transport network，PTN)设备、波分复用(wavelength division multiplexing，WDM)设备或服务器。
“SR”是一种由国际互联网工程任务组(The Internet Engineering Task Force，IETF)推动的路由转发协议。SR定义了如下两种段类型：邻接类型的段(Adjacency Segment，可简称为邻接段)和前缀/节点类型的段(Prefix/Node Segment，可简称为前缀段或节点段)。其中，邻接段指示了当前节点至其邻居节点的一跳路径。前缀段指示了当前节点至网络内相关联节点的一跳或多跳最短路径。例如，按照节点A→节点C→节点O→节点Z的路径转发报文，其中节点C与节点O互为邻居关系。该路径包含了三个段：节点A到节点C的前缀段，节点C到节点O的邻接段和节点O到节点Z的前缀段。
SR利用标签(Label)指导报文转发。与上述两种SR的段类型对应的，标签也可分为邻接标签和前缀标签(或节点标签)。若要让报文从节点A转发到节点Z，可以将该路径包含的上述三个段的标签依次压入报文的标签栈中，即依次压入节点O到节点Z这一前缀段的前缀标签、节点C到节点O这一邻接段的邻接标签和节点A到节点C这一前缀段的前缀标签。例如，头节点A可以根据最后压入的节点A到节点C的段的前缀标签，查询标签转发表项， 根据查表结果，决定是弹出此前缀标签，还是将此前缀标签替换成表项对应的出标签。
“标签块”，为取值连续的一段预留标签。该预留标签的范围的最小值也可称为“基值”。每个转发节点可以为邻接标签和前缀标签分别预留一个标签块，即邻接标签块(SR Local Block，SRLB)和全局标签块(SR Global Block，SRGB)。这两个标签块可以是连续的一段，如SRLB为[16,999]，SRGB为[1000,1999]，或者SRLB和SRGB也可以是独立的两段，如SRLB为[16,999]，SRGB为[5000,5999]。不同转发节点预留的SRLB和SRGB的范围可以相同，也可以不同。
“标签转发表项”，即基于多协议标签交换(MPLS)的转发表项，一般包括下一跳地址、标签操作等等。该标签操作包括弹出(pop)标签、压入(push)标签和交换(swap)标签等。当带标签报文到达转发节点时，转发节点可以根据带标签报文的最外层标签查找标签转发表项。当带标签报文的最外层标签与某个标签转发表项的入标签匹配时，即可根据该匹配的标签转发表项对该带标签报文进行处理。比如，当标签转发表项指示的标签操作为交换标签时，可以将该带标签报文中的外层标签替换成标签转发表项指定的出标签，然后向标签转发表项指定的下一跳地址转发该带标签报文。
“IP前缀”：IP地址段的表示方法可以有以下两种，一种是网络地址和掩码的表示方式，如10.1.1.0 255.255.255；另一种是网络地址/掩码长度的表示方式，如10.1.1.0/24，其中IP前缀指的就是按后一种方式表示的一个IP地址段。一个转发节点可以有多个IP前缀。例如，一个转发节点上有3个本地环回(loopback)接口，每个loopback接口都有各自的IP地址，比如loopback 0接口的IP地址为10.1.1.1/32，loopback 1接口的IP地址为20.1.1.1/24，loopback 2接口的IP地址为30.1.1.1/32，那么该转发节点上就有3个IP前缀，分别为10.1.1.1/32、20.1.1.1/24、30.1.1.1/32。
下面结合说明书附图和各实施例对本公开技术方案进行说明。
本公开实施例提出了一种SID获取方法和装置，通过软件定义网络(Software Defined Networking，SDN)控制器来实现SID的分配和通告。这种方式只需在SDN控制器上运行SR协议，各转发节点上不需要运行SR协议，如此可以充分发挥SDN控制器集中控制的优点，在实现上比较简单。
参见图1，该SID获取方法可包括如下步骤：
在步骤S101，SDN控制器收集网络拓扑；
在步骤S102，SDN控制器获取所述网络拓扑中各转发节点的标签块；
在步骤S103，SDN控制器根据所述网络拓扑和各转发节点的标签块，为各转发节点分配对应的SID；
在步骤S104，SDN控制器将分配好的SID发送给对应的转发节点。
本公开实施例提供的SID获取方法，可应用于图2所示的系统，该系统包括SDN控制器100和多个转发节点，如路由器(R)201、R 202、R 203、R 204和R 205。
SDN控制器100，用于根据网络拓扑和转发节点的标签块，为网络域中的转发节点分配SID，包括为每个转发节点的邻接接口IP(Internet Protocol，网际协议)地址分配邻接标签，为每个转发节点的IP前缀分配前缀标签；以及将分配好的SID发送给相应的转发节点。
转发节点，用于转发报文，在本公开实施例中可以接收并维护SDN控制器100下发的SID。本公开实施例中各转发节点可以不运行SR协议，即转发节点不作SID的分配和通告，直接接收SDN控制器100发送的SID，然后根据接收的SID对本节点上存储的标签转发表项进行激活，根据激活的标签转发表项转发报文。
如图3所示为本公开实施例提供的一种SID获取方法的交互过程图，包括如下步骤。
步骤301：SDN控制器100收集网络拓扑。
SDN控制器100可以通过拓扑收集机制收集网络拓扑。例如，可以通过边界网关协议(Border Gateway Protocol，BGP)报文从网络域中支持BGP的转发节点上收集网络域的链路状态信息(Link State)，然后根据收集到的链路状态信息计算出网络域的网络拓扑。其中，转发节点返回给SDN控制器100的链路状态信息可以携带在BGP更新(update)报文中。
网络拓扑可以包括关于以下各项的信息：网络域中的转发节点，转发节点上的IP前缀，转发节点连接的子网，转发节点之间的链路，以及链路两端的转发节点的接口地址等。
步骤302：SDN控制器100获取所述网络拓扑中各转发节点的标签块。
SDN控制器100可以通过网络配置(Netconf)接口，向网络拓扑中各转发节点发送请求，然后接收网络拓扑中各转发节点返回的响应，转发节点返回的响应中携带了转发节点的标签块。各转发节点返回的标签块包括了各转发节点的SRLB和SRGB。
当然，SDN控制器100也可以通过其它方式获取各转发节点的标签块，如通过简单网络管理协议(Simple Network Management Protocol，SNMP)。
步骤303：SDN控制器100根据所述网络拓扑和各转发节点的标签块，为各转发节点分配对应的SID。
本公开实施例中，SDN控制器100分配的SID主要包括邻接标签和前缀标签。下述以路径上的第一转发节点为例，介绍SDN控制器100如何为转发节点分配邻接标签和前缀标签，其余转发节点可以按照第一转发节点进行处理。
为第一转发节点的邻接接口IP地址分配邻接标签时，执行以下步骤：
第一步，根据步骤301中获得的网络拓扑确定第一转发节点连接的邻接接口的IP地址(以下简称为“邻接接口IP地址”)。其中该邻接接口位于第一转发节点的邻居节点上。例如，如果第一转发节点为图2中的R 201，那么根据网络拓扑可以确定出R 201的邻居节点有R 202和R 203，R 202上与R 201连接的接口的IP地址为A2，R 203上与R 201连接的接口的IP地址为A3，从而R 201的邻接接口IP地址包括A2和A3。
第二步，为确定的第一转发节点的每一邻接接口IP地址分配邻接标签。其中，不同邻接接口IP地址分配不同的邻接标签，并且所分配的邻接标签在第一转发节点的SRLB限定的范围中。例如，如果图2中R 201的SRLB为[16，999]，那么，在[16，999]中，可以为R 201的邻接接口IP地址A2和A3分配不同的邻接标签，如为A2分配邻接标签16，为A3分配邻接标签17。
为第一转发节点的IP前缀分配前缀标签时，执行以下步骤：
第一步，为第一转发节点的每个IP前缀分配索引值，该索引值在网络域内是全局唯一的。
在网络域内，索引值与IP前缀为一一对应关系。
第二步，针对第一转发节点的每一IP前缀，根据该IP前缀被分配的索引值和各个转发节点的SRGB，确定该IP前缀在各个转发节点上的前缀标签。
在一种可选的实现方式中，SDN控制器100可以基于每个转发节点各自的SRGB的基值和该IP前缀的索引值，确定该IP前缀分别在每个转发节点上的前缀标签。例如，在确定第一转发节点的第一IP前缀在第二转发节点上的前缀标签时，可以将第二转发节点的SRGB的基值与第一IP前缀的索引值相加，将得到的和作为第一IP前缀在第二转发节点上的前缀标签，得到的前缀标签应落在第二转发节点的SRGB限定的范围内。
步骤304：SDN控制器100将分配好的SID发送给对应的转发节点。
SDN控制器100可以通过Netconf接口将分配好的SID下发给对应的转发节点。
SID包括邻接标签和前缀标签。
此处SID与转发节点的“对应”关系可以这样理解：为第一转发节点的邻接接口IP地址 分配的邻接标签可以发送给第一转发节点；为第一转发节点的第一IP前缀分配的该第一IP前缀在第二转发节点上的前缀标签，可以被发送给第二转发节点。这里的第二转发节点可以包括第一转发节点以外的一个或多个转发节点。例如，下述表1可以仅发送给R1，下述表2可以仅发送给R2，这样可以减少节点的负担，节省带宽。
可选的，SDN控制器100可以基于分配好的邻接标签生成第一转发信息，第一转发信息包括邻接标签以及与邻接标签对应的下一跳地址；以及SDN控制器100可以基于分配好的前缀标签生成第二转发信息，第二转发信息包括前缀标签以及与前缀标签对应的下一跳地址和出标签。从而，SDN控制器100可以将第一转发信息和第二转发信息发送给对应的转发节点。
以图2中的R 201为例，在下发邻接标签给R 201时，SDN控制器100可以将与该邻接标签相关的下一跳地址一同下发给R 201，如表1所示。
表1
Figure PCTCN2017106853-appb-000001
又例如，仍以图2中的R 201为例，在下发R 201的IP前缀1在R 202上的前缀标签时，SDN控制器100可以将与该前缀标签相关的下一跳地址以及出标签一同下发给R 202，如表2所示。
表2
Figure PCTCN2017106853-appb-000002
相应的，各转发节点上可以设置不同的应用程序编程接口(Application Programming Interface，API)，分别用于接收邻接标签和前缀标签。例如，转发节点可以与SDN控制器100事先约定，通过API 0接收邻接标签，通过API 1接收前缀标签。
以上表1和表2分别示出了标签转发表项的示例。在标签转发表项的入标签为邻接标签的情况下，标签转发表项记录了邻接标签与下一跳地址之间的对应关系。在标签转发表项的入标签为前缀标签的情况下，标签转发表项记录了前缀标签与至下一跳地址的出标签以及下一跳地址之间的对应关系。表1和表2不具有限制性，标签转发表项的内容可以根据需要进行扩展。
步骤305：转发节点根据接收的SID对本节点上存储的标签转发表项进行激活。
可选的，标签转发表项可以预先由转发节点生成，也可以由SDN控制器100生成再下发给转发节点。转发节点或SDN控制器100可以根据如上表1和表2所示的邻接标签、前缀标签和相关的下一跳地址、出标签等信息，为网络拓扑中的各转发路径生成标签转发表项。
其中，转发节点可以直接激活以接收到的邻接标签为入标签的标签转发表项。
转发节点可以激活入标签为接收到的前缀标签且出标签不为空的标签转发表项，以及激活入标签为接收到的前缀标签且出标签为空的标签转发表项。
可选的，如果入标签为前缀标签且出标签不为空的标签转发表项仅有一个，则转发节点可以直接激活这一个标签转发表项；如果入标签为前缀标签且出标签不为空的标签转发表项有多个，则转发节点可以仅激活其中具有最优路由的一个或多个标签转发表项。
实际应用中，转发节点的表项管理模块或代理模块可以通过将标签转发表项安装到节点自身的软件层或硬件层，来实现对标签转发表项的激活。
此处所说的最优路由可以是最短路径路由，也可以指按照其它原则匹配到的最佳匹配路由。以最优路由是最短路径路由为例，只激活最优路由所对应的标签转发表项可以使得报文总是以最短路径转发，从而提高报文传输效率。
步骤306：转发节点对与激活的标签转发表项匹配的报文进行处理。
例如，转发节点可以将报文携带的标签与标签转发表项进行匹配。如果报文携带的标签与某个标签转发表项的入标签匹配，则按照该匹配表项所指示的标签操作，对报文的标签栈进行POP(去掉顶层标签)操作或SWAP(交换标签)操作，并将该报文转发到该匹配表项所指示的下一跳地址。
为了更清楚地说明本公开的技术方案，下面通过一个实施例对上述技术方案做进一步的说明，需要说明的是，此实施例仅仅是本公开的一种实现方式，不构成对本公开的限定。
一网络域内的转发节点路由器(Router)A/B/C/D/E的连接关系参见图4所示，每台设备上都有一个loopback 0接口，Router A上额外有一个loopback 1接口。设备的路由器标识(Router ID)设置为loopback 0接口的IP地址。本实施例以每台设备的所有邻接接口IP地址对应的邻接标签和设备上的一个loopback接口的IP地址/子网掩码长度对应的IP前缀为例，说明邻接标签和前缀标签。表3所示为各转发节点的预配置信息。
表3
Figure PCTCN2017106853-appb-000003
1、控制器400收集网络域的链路状态信息，计算出网络拓扑，得到的网络拓扑可以如表4所示。
表4
Figure PCTCN2017106853-appb-000004
2、控制器400通过Netconf接口，从各转发节点处获取该转发节点的两种类型的SR标签块：SRLB和SRGB。得到的SR标签块可以如表5所示。
表5
Router ID SRGB SRLB
5.5.5.5 [5000,5999] [16,999]
6.6.6.6 [6000,6999] [16,999]
7.7.7.7 [7000,7999] [16,999]
8.8.8.8 [8000,8999] [16,999]
9.9.9.9 [9000,9999] [16,999]
3、控制器400为表4所示的网络拓扑中转发节点上的IP前缀，分配全局唯一的Index。 Index可以认为是相对于SRGB基值的一个偏移值，可以从0开始按1递增分配。表6所示为控制器400记录的一种IP前缀与Index之间的对应关系。控制器400可以持久化保存IP前缀与Index之间的对应关系，从而使得控制器400在发生故障并恢复正常后，在故障前后生成的标签转发表项可以保持一致，从而保证报文的正常转发。
表6
Figure PCTCN2017106853-appb-000005
如果一个转发节点上有多个IP前缀，那么每个IP前缀也相应的分配一个全局唯一的Index，比如，Router A上有两个IP前缀，这两个IP前缀分别对应一个Index。
4、控制器400根据网络拓扑、各IP前缀的索引值和各转发节点的SRGB标签块，为每个IP前缀分别分配在不同转发节点上的前缀标签，标签值为转发节点的SRGB的基值加上IP前缀的索引值得到的和。
参见表7-1和表7-2。表7-1示出了Router A上的IP前缀5.5.5.5/32(分配的Index为0)在每个转发节点上的前缀标签和出标签。表7-2示出了Router C上的IP前缀6.6.6.6/32(分配的Index为2)IP地址前缀在每个转发节点上的前缀标签和出标签。本公开实施例仅列举出了两个IP前缀在各转发节点上的前缀标签，其余IP前缀在各转发节点上的前缀标签可依次类推，不再一一列出。
表7-1
Figure PCTCN2017106853-appb-000006
Figure PCTCN2017106853-appb-000007
表7-2
Figure PCTCN2017106853-appb-000008
Figure PCTCN2017106853-appb-000009
表7-1和表7-2中提及到的下一跳的出标签，为该IP前缀在下一跳节点上的前缀标签。当节点A要向相邻的节点B转发报文时，节点A会根据该报文携带的标签查询本地的标签转发表项以找到匹配的到达节点B的出标签。然后节点A将该报文携带的标签交换(swap)为达节点B的出标签，并转发给下一跳节点B。该报文在节点A的出标签对应于该报文在节点B的入标签，节点B同样进行标签交换，为该报文打上到下一跳节点C的出标签。
表7-1和表7-2中均示出了某一前缀标签对应多个出标签、即某一前缀标签对应多个标签转发表项的情况，但是在实际应用中，转发节点可以根据预先配置的最优路由来决定激活哪个标签转发表项。举例来说，表7-1中，IP前缀5.5.5.5/32在Router A(Router ID 5.5.5.5)上的前缀标签为5000，IP前缀5.5.5.5/32在Router C(Router ID 6.6.6.6)上的前缀标签为6000。与前缀标签6000对应的出标签有两项：出标签5000和出标签8000。Router C根据预先配置的最优路由可知到Router A的路径优于到Router D的路径，因此只激活与入标签6000和出标签5000相对应的标签转发表项。参见图4，如果Router C收到的报文带有前缀标签6000，则Router C通过查询激活的标签转发表项即可知晓该报文要到达或者经过IP前缀5.5.5.5/32所在的节点，即Router A；Router C用标签5000替换掉该报文原先携带的标签6000，然后转发给其下一跳Router A。
特别的，如果每个转发节点的SRGB均相同，那么同一个IP前缀在每个转发节点上分配的前缀标签也会相同，这是一种较为简单的情况。
5、控制器400根据网络拓扑和各转发节点的SRLB标签块，为各转发节点的每个邻接接口IP地址分配邻接标签，分配好的邻接标签如表8所示。
表8
Figure PCTCN2017106853-appb-000010
Figure PCTCN2017106853-appb-000011
6、SDN控制器400将分配好的邻接标签以及与邻接标签相关的下一跳地址，分配好的前缀标签以及与之相关的下一跳地址和出标签，一起通过Netconf接口发送给对应的转发节点。
邻接标签和前缀标签以及相关信息可以只发送给对应的节点。如，表8中的每一行包括的邻接标签和对应的下一跳地址可以只发送给该行的第一列Router ID对应的节点。以表8中的最后一行为例，为Router E(Router ID 9.9.9.9)分配的邻接标签等信息可以只发送给Router E，向Router E发送的邻接标签和对应的下一跳地址可以如下表9所示。
表9
In-Label Next Hop
16 79.1.1.7
17 89.1.1.8
又如，表7-1和表7-2中的每一行包括的前缀标签和对应的下一跳地址及出标签可以只发送给该行的第一列Router ID对应的节点。以表7-1中的第一行和第二行为例，IP前缀5.5.5.5/32在Router A(Router ID 5.5.5.5)上的前缀标签等信息可以只发送给Router A，向Router A发送的前缀标签和对应的下一跳地址及出标签可以如下表10所示。而IP前缀5.5.5.5/32在Router C(Router ID 6.6.6.6)上的前缀标签等信息可以只发送给Router C，相应的前缀标签和对应的下一跳地址及出标签可以如下表11所示。
表10
In-Label Out-Label Next Hop
5000 空(NULL) NULL
表11
In-Label Out-Label Next Hop
6000 5000 56.1.1.5
6000 8000 68.1.1.8
7、转发节点收到对应的邻接标签和前缀标签等信息后，获取本节点的标签转发表项，并对标签转发表项进行激活。
具体的，转发节点可以直接激活入标签为收到的邻接标签的所有标签转发表项；以及，激活入标签为收到的前缀标签且出标签不为空的标签转发表项；以及，激活入标签为收到的前缀标签且出标签为空(即Null)的标签转发表项。
如果入标签为前缀标签且出标签不为空的标签转发表项仅有一个，则转发节点可以直接激活这一个标签转发表项；如果入标签为前缀标签且出标签不为空的标签转发表项有多个，则转发节点可以仅激活其中具有最优路由的一个或多个标签转发表项。
例如，对于上述表11包括两个下一跳地址，表示报文从Router C转发到IP前缀5.5.5.5/32所在的转发节点RouterA(报文转发到Router A后，可能终结转发，也可能还需要继续转发)可以有两条转发路径，但由于IP前缀5.5.5.5/32在Router C上的最优路由只有一个下一跳56.1.1.5，所以Router C可以只激活表11的第一行，即只激活出标签/下一跳：5000/56.1.1.5。也就是说，Router C对于IP地址5.5.5.5，激活的标签转发表项只有出标签/下一跳为5000/56.1.1.5的标签转发表项。
8、转发路径建立。
这一过程由SDN控制器向路径的头节点下发路径信息实现，路径信息是一个标签序列，标签序列中的各个标签代表路径所关联的各个段，比如，图4中一条从Router E到Router A的路径可以关联以下两个段：Router E到Router D的邻接段，和Router D到Router A的前缀段。结合上述表8，SDN控制器可以根据Router E的ID(9.9.9.9)及Router E与Router D的接口连接关系(89.1.1.9—89.1.1.8)，查找到Router E到Router D这一邻接段的邻接标签为 17；结合上述表7-1，SDN控制器可以查找到Router A上的IP前缀5.5.5.5/32在Router D(ID为8.8.8.8)上的前缀标签为8000，即Router D到Router A的前缀段的前缀标签为8000；从而SDN控制器向SR路径的头节点Router E下发代表这两个段的标签序列[17，8000]，即可完成这一转发路径的建立。
9、转发节点按照激活的标签转发表项对带标签报文进行处理。
例如，如果Router E想通过在上述第8步的例子中建立的路径转发报文时(需要注意的是，该报文可以是到达Router A就终结，也可以是经过Router A后继续转发)，只需要通过设置静态路由或者PBR(Policy Based Routing，基于策略的路由)等方式将报文引入路径，将标签序列[17，8000]封装进该报文的标签域中(先压入标签8000，再压入标签17)。然后根据此时报文的外层标签17查询标签转发表项，根据查询结果将封装进该报文中的标签17弹出，然后将该报文发送给下一跳Router D。Router D收到该报文，匹配到该报文的外层标签为8000，根据激活的标签转发表项，可以用标签6000替换掉该报文携带的标签8000，然后将该报文转发给下一跳Router C，或者，Router D也可以用标签7000替换掉该报文携带的标签8000，然后将该报文转发给下一跳Router B。
后续各节点对该报文的处理类似，此处不再赘述。
最终，该报文到达Router A时，Router A匹配到该报文的外层标签为5000，通过查找标签转发表项，弹出标签5000，之后Router A再根据该报文的IP封装或其它类型封装进行处理。
例如，如果该报文弹出标签后显现的目的IP地址为Router A的IP地址，则Router A终结该报文的转发，如果该报文显现的目的IP地址不为Router A的IP地址，则Router A可以再结合路由转发表对该报文进行转发。
综上所述，本公开提供的技术方案通过SDN控制器来实现SID的分配和通告，这种方式只需在SDN控制器上运行SR协议，如此可以充分发挥SDN控制器集中控制的优点，在实现上比较简单。
以上对本公开提供的方法进行了描述。下面对本公开提供的装置进行描述：
本公开的示例提供一种SDN控制器，适用于上述SID获取方法，如图5所示，SDN控制器包括收集模块501、获取模块502、分配模块503和发送模块504。
收集模块501，用于收集网络拓扑。
获取模块502，用于获取所述网络拓扑中各转发节点的标签块。
分配模块503，用于根据所述网络拓扑和各转发节点的标签块，为各转发节点分配对应的SID。
发送模块504，用于将分配好的SID发送给对应的转发节点。
在一个示例中，获取模块502可以具体用于：通过Netconf接口向网络拓扑中各转发节点发送请求，接收网络拓扑中各转发节点返回的响应，转发节点返回的响应携带了转发节点的标签块。
在一个示例中，当所述标签块包括SRLB时，分配模块503具体用于：根据所述网络拓扑确定各转发节点连接的邻接接口的IP地址，所述邻接接口处于该转发节点的邻居节点上；为每一邻接接口IP地址分配邻接标签，其中，每一转发节点连接的不同邻接接口IP地址被分配不同的邻接标签，并且所分配的邻接标签在每一转发节点的SRLB的范围中。
在一个示例中，当所述标签块包括SRGB时，分配模块503具体用于：为各个转发节点的IP前缀分配索引值；根据每一IP前缀被分配的索引值和各个转发节点的SRGB，确定每一IP前缀在各个转发节点上的前缀标签。
在一个示例中，在将分配好的SID发送给对应的转发节点时，发送模块504具体用于：将分配好的邻接标签发送给对应的转发节点，以使在所述邻接标签与标签转发表项的入标签匹配时激活所述标签转发表项，其中，所述邻接标签为针对所述对应的转发节点所连接的邻接接口的网际协议IP地址分配的标签；以及
将分配好的前缀标签发送给对应的转发节点，以使在所述前缀标签与标签转发表项的入标签匹配时激活所述标签转发表项，其中，所述前缀标签为各转发节点的IP前缀在所述对应的转发节点上的前缀标签。
在一个示例中，分配模块503还可以用于：基于分配好的邻接标签生成第一转发信息，所述第一转发信息包括邻接标签以及与邻接标签对应的下一跳地址；基于分配好的前缀标签生成第二转发信息，所述第二转发信息包括前缀标签以及与前缀标签对应的下一跳地址和标签转发表项的出标签。
相应的，在将分配好的SID发送给对应的转发节点时，发送模块504具体用于：将所述第一转发信息和第二转发信息分别发送给对应的转发节点。
本实施例中未尽之细节可参考上述图3所示方法中SDN控制器的描述，在此不再赘 述。
需要说明的是，本公开实施例中对单元的划分是示意性的，仅仅为一种逻辑功能划分，实际实现时可以有另外的划分方式。在本公开的实施例中的各功能单元可以集成在一个处理单元中，也可以是各个单元单独物理存在，也可以两个或两个以上单元集成在一个单元中。上述集成的单元既可以采用硬件的形式实现，也可以采用软件功能单元的形式实现。
基于上述提供的SID获取方法，本公开还提供一种SDN控制器，如图6所示，SDN控制器包括通信接口601、处理器602、存储介质603和总线604；其中，通信接口601、处理器602、存储器603通过总线604完成相互间的通信。
其中，通信接口501，用于与网元通信，比如与转发节点通信。处理器502可以是一个中央处理器CPU。存储介质603可以是任何电子、磁性、光学或其它物理存储装置，可以包含或存储信息，如可执行指令、数据，等等。例如，存储介质可以是：RAM(Radom Access Memory，随机存取存储器)、易失存储介质、非易失性存储介质、闪存、存储驱动器(如硬盘驱动器)、固态硬盘、任何类型的存储盘。并且存储介质603中存储有逻辑指令，处理器602可以执行存储介质603中存储的SID获取逻辑指令，以实现上述的SID获取方法中SDN控制器的功能，参见图3所示的流程。
例如，在处理器602读取并执行存储介质603中的逻辑指令时，该处理器602被促使执行以下操作：
收集网络拓扑；
获取所述网络拓扑中各转发节点的标签块；
根据所述网络拓扑和各转发节点的标签块，为各转发节点分配对应的SID；
将分配好的SID发送给对应的转发节点。
其中，在获取所述网络拓扑中各转发节点的标签块时，处理器602还被促使：
通过网络配置Netconf接口向所述网络拓扑中各转发节点发送请求，
接收所述网络拓扑中各转发节点返回的响应，转发节点返回的响应携带了所述转发节点的标签块。
其中，在根据所述网络拓扑和各转发节点的标签块，为各转发节点分配对应的SID时，处理器602还被促使：
根据所述网络拓扑确定每个转发节点连接的邻接接口的网际协议IP地址，所述邻接接口处于该转发节点的邻居节点上；
为所述邻接接口的IP地址分配邻接标签，其中，所述每个转发节点连接的不同邻接接口的IP地址被分配不同的邻接标签，并且所分配的邻接标签在所述每个转发节点的所述标签块内包括的SRLB的范围中。
其中，在根据网络拓扑和各转发节点的标签块，为各转发节点分配对应的SID时，处理器602还被促使：
为各个转发节点的IP前缀分配索引值；
根据每一IP前缀被分配的索引值和各个转发节点的所述标签块内包括的SRGB，确定每一IP前缀在各个转发节点上的前缀标签。
其中，SID包括邻接标签和前缀标签，在将分配好的SID发送给对应的转发节点时，处理器602还被促使：
将分配好的邻接标签发送给对应的转发节点，以使在所述邻接标签与标签转发表项的入标签匹配时激活所述标签转发表项，其中，所述邻接标签为针对所述对应的转发节点连接的邻接接口的网际协议IP地址分配的标签；
以及，将分配好的前缀标签发送给对应的转发节点，以使在所述前缀标签与标签转发表项的入标签匹配时激活所述标签转发表项，其中，所述前缀标签为各转发节点的IP前缀在所述对应的转发节点上的前缀标签。
其中，在将分配好的邻接标签发送给对应的转发节点时，处理器602还被促使：
基于分配好的邻接标签生成第一转发信息，所述第一转发信息包括邻接标签以及与邻接标签对应的下一跳地址；
将所述第一转发信息发送给对应的转发节点。
其中，在将分配好的前缀标签发送给对应的转发节点时，处理器502还被促使：
基于分配好的前缀标签生成第二转发信息，所述第二转发信息包括前缀标签以及与前缀标签对应的下一跳地址和所述标签转发表项的出标签；
将所述第二转发信息发送给对应的转发节点。
基于本公开上述提供的SID获取方法，本公开实施例提供一种适用于上述方法的转发节点，如图7所示，所述转发节点包括接收模块701、激活模块702和处理模块703。
接收模块701，用于接收SDN控制器下发的SID，所述SID是所述SDN控制器分配的。
激活模块702，用于根据接收的SID对本节点上的标签转发表项进行激活。
处理模块703，用于对与激活的标签转发表项匹配的报文进行处理。
在一个示例中，接收的SID包括为本节点连接的邻接接口的IP地址分配的邻接标签和各转发节点的IP前缀在本节点上的前缀标签；激活模块702具体用于：激活入标签为所述邻接标签的标签转发表项；激活入标签为所述前缀标签的标签转发表项。
需要说明的是，本公开实施例中对单元的划分是示意性的，仅仅为一种逻辑功能划分，实际实现时可以有另外的划分方式。在本公开的实施例中的各功能单元可以集成在一个处理单元中，也可以是各个单元单独物理存在，也可以两个或两个以上单元集成在一个单元中。上述集成的单元既可以采用硬件的形式实现，也可以采用软件功能单元的形式实现。
本实施例中未尽之细节可参考上述图3所示方法中转发节点的描述，在此不再赘述。
基于上述提供的SID获取方法，本公开实施例还提供一种转发节点，如图8所示，转发节点包括通信接口801、处理器802、存储介质803和总线804；其中，通信接口801、处理器802、存储介质803通过总线804完成相互间的通信。
其中，通信接口801，用于与网元通信，比如与SDN控制器通信。处理器802可以是一个中央处理器CPU。存储器803可以是任何电子、磁性、光学或其它物理存储装置，可以包含或存储信息，如可执行指令、数据，等等。例如，存储介质可以是：RAM(Radom Access Memory，随机存取存储器)、易失存储介质、非易失性存储介质、闪存、存储驱动器(如硬盘驱动器)、固态硬盘、任何类型的存储盘。并且存储介质803中存储有逻辑指令，处理器802可以执行存储介质803中存储的SID获取逻辑指令，以实现上述的SID获取方法中转发节点的功能，参见图3所示的流程。
例如，在处理器802读取并执行存储介质803中的逻辑指令时，该处理器802被促使执行以下操作：
接收SDN控制器下发的SID，所述SID是所述SDN控制器分配的；
根据接收的SID对本节点上存储的标签转发表项进行激活；
对与激活的标签转发表项匹配的报文进行处理。
对于装置实施例而言，由于其基本对应于方法实施例，所以相关之处参见方法实施例的部分说明即可。以上所描述的装置实施例仅仅是示意性的，其中所述作为分离部件说明的单元可以是或者也可以不是物理上分开的，作为单元显示的部件可以是或者也可以不是物理单元，即可以位于一个地方，或者也可以分布到多个网络单元上。可以根据实际的需要选择 其中的部分或者全部模块来实现本公开方案的目的。本领域普通技术人员在不付出创造性劳动的情况下，即可以理解并实施。
需要说明的是，在本文中，诸如第一和第二等之类的关系术语仅仅用来将一个实体或者操作与另一个实体或操作区分开来，而不一定要求或者暗示这些实体或操作之间存在任何这种实际的关系或者顺序。术语“包括”、“包含”或者其任何其他变体意在涵盖非排他性的包含，从而使得包括一系列要素的过程、方法、物品或者设备不仅包括那些要素，而且还包括没有明确列出的其他要素，或者是还包括为这种过程、方法、物品或者设备所固有的要素。在没有更多限制的情况下，由语句“包括一个……”限定的要素，并不排除在包括所述要素的过程、方法、物品或者设备中还存在另外的相同要素。
以上对本发明实施例所提供的方法和装置进行了详细介绍，本文中应用了具体个例对本发明的原理及实施方式进行了阐述，以上实施例的说明只是用于帮助理解本发明的方法及其核心思想；同时，对于本领域的一般技术人员，依据本发明的思想，在具体实施方式及应用范围上均会有改变之处，综上所述，本说明书内容不应理解为对本发明的限制。

Claims (14)

  1. 一种段标识SID获取方法，包括：
    软件定义网络SDN控制器收集网络拓扑；
    所述SDN控制器获取所述网络拓扑中各转发节点的标签块；
    所述SDN控制器根据所述网络拓扑和各转发节点的标签块，为各转发节点分配对应的SID；
    所述SDN控制器将分配好的所述SID发送给对应的转发节点。
  2. 如权利要求1所述的方法，其中，获取所述网络拓扑中各转发节点的标签块包括：
    所述SDN控制器通过网络配置Netconf接口向所述网络拓扑中各转发节点发送请求，
    所述SDN控制器接收所述网络拓扑中各转发节点返回的响应，所述转发节点返回的响应携带了所述转发节点的标签块。
  3. 如权利要求1所述的方法，其中，根据所述网络拓扑和各转发节点的标签块，为各转发节点分配对应的SID包括：
    根据所述网络拓扑，所述SDN控制器确定每个转发节点连接的邻接接口的网际协议IP地址，所述邻接接口处于该转发节点的邻居节点上；
    所述SDN控制器为所述邻接接口的IP地址分配邻接标签，其中，所述每个转发节点连接的不同邻接接口的IP地址被分配不同的邻接标签，并且所分配的邻接标签在所述每个转发节点的所述标签块内包括的段路由邻接标签块SRLB的范围中。
  4. 如权利要求1所述的方法，其中，根据所述网络拓扑和各转发节点的标签块，为各转发节点分配对应的SID包括：
    所述SDN控制器为各个转发节点的网际协议IP前缀分配索引值；
    所述SDN控制器根据每一IP前缀被分配的索引值和各个转发节点的所述标签块内包括的段路由全局标签块SRGB，确定每一IP前缀在各个转发节点上的前缀标签。
  5. 如权利要求1所述的方法，其中，SID包括邻接标签和前缀标签，
    将分配好的所述SID发送给对应的转发节点包括：
    所述SDN控制器将分配好的邻接标签发送给对应的转发节点，以使在所述邻接标签与标签转发表项的入标签匹配时激活所述标签转发表项，其中，所述邻接标签为针对所述对应的转发节点连接的邻接接口的网际协议IP地址分配的标签；以及，
    所述SDN控制器将分配好的前缀标签发送给对应的转发节点，以使在所述前缀标签与标签转发表项的入标签匹配时激活所述标签转发表项，其中，所述前缀标签为各转发节点的IP 前缀在所述对应的转发节点上的标签。
  6. 如权利要求5所述的方法，其中，将分配好的所述邻接标签发送给对应的转发节点包括：
    所述SDN控制器基于分配好的所述邻接标签生成第一转发信息，所述第一转发信息包括所述邻接标签以及与所述邻接标签对应的下一跳地址；
    所述SDN控制器将所述第一转发信息发送给对应的转发节点。
  7. 如权利要求5所述的方法，其中，将分配好的所述前缀标签发送给对应的转发节点包括：
    所述SDN控制器基于分配好的所述前缀标签生成第二转发信息，所述第二转发信息包括所述前缀标签，以及与所述前缀标签对应的下一跳地址和所述标签转发表项的出标签；
    所述SDN控制器将所述第二转发信息发送给对应的转发节点。
  8. 一种软件定义网络SDN控制器，包括：
    处理器，以及
    存储有机器可执行指令的机器可读存储介质，通过读取并执行所述机器可执行指令，所述处理器被促使：
    收集网络拓扑；
    获取所述网络拓扑中各转发节点的标签块；
    根据所述网络拓扑和各转发节点的标签块，为各转发节点分配对应的段标识SID；
    将分配好的所述SID发送给对应的转发节点。
  9. 如权利要求8所述的控制器，其中，在获取所述网络拓扑中各转发节点的标签块时，所述处理器还被所述机器可执行指令促使：
    通过网络配置Netconf接口向所述网络拓扑中各转发节点发送请求，
    接收所述网络拓扑中各转发节点返回的响应，所述转发节点返回的响应携带了所述转发节点的标签块。
  10. 如权利要求8所述的控制器，其中，在根据所述网络拓扑和各转发节点的标签块，为各转发节点分配对应的SID时，所述处理器还被所述机器可执行指令促使：
    根据所述网络拓扑，确定每个转发节点连接的邻接接口的网际协议IP地址，所述邻接接口处于该转发节点的邻居节点上；
    为所述邻接接口的IP地址分配邻接标签，其中，所述每个转发节点连接的不同邻接接口的IP地址被分配不同的邻接标签，并且所分配的邻接标签在所述每个转发节点的所述标签块 内包括的段路由邻接标签块SRLB的范围中。
  11. 如权利要求8所述的控制器，其中，在根据所述网络拓扑和各转发节点的标签块，为各转发节点分配SID时，所述处理器还被所述机器可执行指令促使：
    为各个转发节点的网际协议IP前缀分配索引值；
    根据每一IP前缀被分配的索引值和各个转发节点的所述标签块内包括的段路由全局标签块SRGB，确定每一IP前缀在各个转发节点上的前缀标签。
  12. 如权利要求8所述的控制器，其中，SID包括邻接标签和前缀标签，
    在将分配好的所述SID发送给对应的转发节点时，所述处理器还被所述机器可执行指令促使：
    将分配好的邻接标签发送给对应的转发节点，以使在所述邻接标签与标签转发表项的入标签匹配时激活所述标签转发表项，其中，所述邻接标签为针对所述对应的转发节点连接的邻接接口的网际协议IP地址分配的标签；
    以及，将分配好的前缀标签发送给对应的转发节点，以使在所述前缀标签与标签转发表项的入标签匹配时激活所述标签转发表项，其中，所述前缀标签为各转发节点的IP前缀在所述对应的转发节点上的标签。
  13. 如权利要求12所述的控制器，其中，在将分配好的所述邻接标签发送给对应的转发节点时，所述处理器还被所述机器可执行指令促使：
    基于分配好的所述邻接标签生成第一转发信息，所述第一转发信息包括所述邻接标签以及与所述邻接标签对应的下一跳地址；
    将所述第一转发信息发送给对应的转发节点。
  14. 如权利要求12所述的控制器，其中，在将分配好的所述前缀标签发送给对应的转发节点时，所述处理器还被所述机器可执行指令促使：
    基于分配好的所述前缀标签生成第二转发信息，所述第二转发信息包括所述前缀标签，以及与所述前缀标签对应的下一跳地址和所述标签转发表项的出标签；
    将所述第二转发信息发送给对应的转发节点。
PCT/CN2017/106853 2016-10-20 2017-10-19 段标识sid获取 WO2018072728A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201610915623.0A CN107968752B (zh) 2016-10-20 2016-10-20 一种sid获取方法和装置
CN201610915623.0 2016-10-20

Publications (1)

Publication Number Publication Date
WO2018072728A1 true WO2018072728A1 (zh) 2018-04-26

Family

ID=61996485

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2017/106853 WO2018072728A1 (zh) 2016-10-20 2017-10-19 段标识sid获取

Country Status (2)

Country Link
CN (1) CN107968752B (zh)
WO (1) WO2018072728A1 (zh)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110086671A (zh) * 2019-04-30 2019-08-02 电子科技大学 一种Ad Hoc网络的拓扑发现方法
CN114826999A (zh) * 2022-03-22 2022-07-29 北京邮电大学 卫星网络数据传输方法及装置
CN115037690A (zh) * 2022-06-21 2022-09-09 阿里巴巴（中国）有限公司 一种流量调度方法、装置、电子设备及存储介质

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112702266A (zh) * 2018-06-29 2021-04-23 华为技术有限公司 生成标签转发表的方法、报文发送方法、装置及设备
CN110971433B (zh) * 2018-09-29 2022-02-22 华为技术有限公司 获取SRv6隧道信息的方法、设备和系统
CN111510388B (zh) 2019-01-30 2022-01-21 华为技术有限公司 一种确定转发路径的方法、装置及系统
CN113645136B (zh) * 2019-03-11 2022-12-06 华为技术有限公司 网络中报文转发的方法、网络节点、网络系统
US11277334B2 (en) * 2019-07-24 2022-03-15 Juniper Networks, Inc. Using and processing per slice segment identifiers in a network employing segment routing
CN110995596B (zh) * 2019-12-20 2022-04-12 锐捷网络股份有限公司 基于SRv6网络的SID分配方法和装置
CN111930757B (zh) * 2020-09-24 2021-01-12 南京中兴软件有限责任公司 数据处理方法、系统、封装节点和解封装节点
CN112350933A (zh) * 2020-10-30 2021-02-09 中电积至(海南)信息技术有限公司 一种状态共享的分布式多出口路由选择方法
CN113691451B (zh) * 2021-09-22 2022-08-19 新华三技术有限公司 一种段标识确定方法及装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150326675A1 (en) * 2014-05-12 2015-11-12 Telefonaktiebolaget L M Ericsson (Publ) Scalable segment identifier allocation in segment routing
CN105075195A (zh) * 2013-03-15 2015-11-18 思科技术公司 分段路由上的标签分发协议
CN105450437A (zh) * 2014-09-19 2016-03-30 中兴通讯股份有限公司 一种分配sid的方法和sr节点

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10194414B2 (en) * 2013-01-07 2019-01-29 Futurewei Technologies, Inc. Information centric networking based service centric networking
US20150245392A1 (en) * 2014-02-27 2015-08-27 Futurewei Technologies, Inc. System and method for optimized route mobility management
CN105991437B (zh) * 2015-02-16 2020-05-15 中兴通讯股份有限公司 报文转发处理方法、装置、控制器及路由转发设备
CN105491024A (zh) * 2015-11-24 2016-04-13 北京邮电大学 一种udp端口的复用方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105075195A (zh) * 2013-03-15 2015-11-18 思科技术公司 分段路由上的标签分发协议
US20150326675A1 (en) * 2014-05-12 2015-11-12 Telefonaktiebolaget L M Ericsson (Publ) Scalable segment identifier allocation in segment routing
CN105450437A (zh) * 2014-09-19 2016-03-30 中兴通讯股份有限公司 一种分配sid的方法和sr节点

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
STEFANO, P. ET AL.: "Segment Routing Application Segment", IP.COM JOURNAL, 30 June 2014 (2014-06-30), XP013163235, ISSN: 1533-0001 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110086671A (zh) * 2019-04-30 2019-08-02 电子科技大学 一种Ad Hoc网络的拓扑发现方法
CN114826999A (zh) * 2022-03-22 2022-07-29 北京邮电大学 卫星网络数据传输方法及装置
CN115037690A (zh) * 2022-06-21 2022-09-09 阿里巴巴（中国）有限公司 一种流量调度方法、装置、电子设备及存储介质

Also Published As

Publication number Publication date
CN107968752A (zh) 2018-04-27
CN107968752B (zh) 2020-07-07

Similar Documents

Publication Publication Date Title
WO2018072728A1 (zh) 段标识sid获取
JP6506475B2 (ja) ビットインデックス付きエクスプリシットレプリケーションを実現する方法及びビット転送ルータ
WO2021063232A1 (zh) 建立bier转发表项的方法、装置和系统
US10097446B2 (en) Dynamic area filtering for link-state routing protocols
CN109995634B (zh) 一种组播虚拟专用网络的承载方法和设备
CN106656781B (zh) 一种报文传输的方法、装置和系统
US10637768B1 (en) Enabling non-flexible-algorithm routers to participate in flexible-algorithm routing protocols
US9998368B2 (en) Zone routing system
CN108259341B (zh) 一种前缀标签分配方法和sdn控制器
US11405283B2 (en) Connections and accesses for hierarchical path computation element (PCE)
WO2015192501A1 (zh) 地址信息的发布方法及装置
CN101243648B (zh) 用于使能标签交换数据分组的路由选择的方法和装置
CN110912796B (zh) 一种通信方法、设备和系统
WO2016131225A1 (zh) 报文转发处理方法、装置、控制器及路由转发设备
CN106572021B (zh) 一种实现网络虚拟化叠加的方法与网络虚拟化边缘节点
WO2011103781A2 (zh) 身份标识与位置分离的实现方法、设备及数据封装方法
EP2708001A1 (en) Label switched routing to connect low power network domains
CN110896379B (zh) 报文的发送方法、绑定关系的通告方法、装置及存储介质
CN112868214B (zh) 分组内的协调负载转移oam记录
WO2021143279A1 (zh) 段路由业务处理方法和装置、路由设备及存储介质
US20120124238A1 (en) Prioritization of routing information updates
WO2022184169A1 (zh) 报文转发方法、系统、存储介质及电子装置
US20210281507A1 (en) Parameter notification and obtaining methods and devices, and storage medium
EP4224817A1 (en) Method and apparatus for determining next hop
CN109361782B (zh) 一种报文转发方法及网络设备

Legal Events

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

Ref document number: 17862692

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: 17862692

Country of ref document: EP

Kind code of ref document: A1