A deterministic forwarding processing method and device based on an IPv4 network

Abstract

The application relates to the technical field of network communication, and discloses a deterministic forwarding processing method and device based on an IPv4 network, which comprises the following steps: a controller issues service flow information to a first node; the first node matches corresponding service flow according to a service flow characteristic policy in the service flow information, inserts a corresponding outer IPv4 header, a segment routing header field SRH and a segment routing operation field SR-OPT in front of an original IPv4 header of the service flow, and encapsulates the service flow to obtain a message; the first node performs deterministic forwarding processing on the message according to a deterministic processing method parameter table DNET and an outer IPv4 header destination address in the message; and if no congestion and no link failure occur in a transmission path from a sending end to a receiving end, it is judged whether nodes on the transmission path from the sending end to the receiving end, except the first node, support deterministic forwarding. The application can realize the functions of deterministic low latency, low jitter and high reliability service guarantee.

Description

Technical Field

[0001] This application relates to the field of network communication technology, and in particular to a deterministic forwarding processing method and apparatus based on IPv4 networks. Background Technology

[0002] Typical deterministic network techniques (see) Figure 1 Flexible Ethernet (FlexE) achieves bandwidth and low latency guarantees through a FlexE Shim layer inserted between the physical and MAC layers, using time-slot hard pipes. Time-Sensitive Networking (TSN) achieves low jitter and bounded latency based on the IEEE 802.1 TSN protocol family. Deterministic IP Networking (DIP) is a Layer 3 deterministic network solution that uses periodic scheduling to achieve deterministic forwarding. However, FlexE and TSN technologies suffer from issues such as resource allocation fixation, inflexible scheduling, and incompatibility with Layer 3 IPv4 networks. Summary of the Invention

[0003] In view of this, this application provides a deterministic forwarding processing method and apparatus based on IPv4 network in traditional IPv4 Ethernet network, which can realize deterministic path transmission, low latency, low jitter and high reliability service guarantee capabilities.

[0004] This application discloses a deterministic forwarding processing method based on IPv4 networks, which includes:

[0005] Step 1: The controller sends service flow information to the first node; the first node is the first node on the transmission path of the message from the sender to the receiver; the node is a network device with routing and switching functions; the service flow information includes path planning, time slot scheduling, queue bandwidth scheduling, and service flow characteristic policies.

[0006] Step 2: The first node matches the corresponding service flow according to the service flow feature strategy in the service flow information, inserts the corresponding outer IPv4 header, Segmentation Routing Header (SRH) field, and Segmentation Routing Operation (SR-OPT) field before the original IPv4 header for the service flow, and encapsulates it to obtain a packet; the service flow features include source IP address, destination IP address, source port number, destination port number, and protocol number; the Segmentation Routing Header (SRH) field is a deterministic transmission path field constructed from the sender to the receiver, and the Segmentation Routing Operation (SR-OPT) field is a deterministic processing method parameter table (DNET) of the nodes on the transmission path; the deterministic processing method parameter table (DNET) includes time slot scheduling, queue number, and queue bandwidth;

[0007] Step 3: The first node performs deterministic forwarding processing on the packet according to the deterministic processing method parameter table DNET and the destination address of the outer IPv4 header in the packet encapsulated in Step 2; the deterministic forwarding processing refers to controlling the forwarding time, selecting the forwarding queue, and guaranteeing the bandwidth of the packet according to the deterministic processing method parameter table DNET.

[0008] Step 4: If there is no congestion or link failure on the transmission path from the sender to the receiver, determine whether the nodes on the transmission path from the sender to the receiver, excluding the first node, support deterministic forwarding.

[0009] Further, step 1 includes:

[0010] The controller determines the path planning of network nodes and the time slot scheduling, queue number and bandwidth of each node between the first node and the last node according to the network node topology information, network status, service flow characteristics, service flow, bandwidth and latency requirements from the sending end to the receiving end; the path planning is the segment list SID in the segmented route header; the segment list SID is a series of ordered IPv4 network segments, representing the node addresses that the data packet needs to pass through in sequence on the network transmission path; the order of the segment list SID is from back to front, that is, SID[0] represents the address of the last node to be passed through on the planned transmission path; SID[0] is the address of the last node;

[0011] Based on the different service quality requirements of service flows, scheduling queues with different bandwidths are allocated to the service flows. The network device's outgoing port has N queues, and the bandwidth of each queue is D. The bandwidth is not greater than the total bandwidth of the output port. In each transmission cycle T, only one of the N queues is used to send data packets. For the i-th queue, Let be the bandwidth of the i-th queue. This represents the total number of queues at the output ports.

[0012] Under the control of the gating list of network devices, the first queue sends messages in the first transmission cycle; the second queue sends messages in the second transmission cycle; and so on. By sending messages within a specified time range through the queues on each node, the time limit and bandwidth of the message on the entire transmission path are determined, thereby realizing deterministic forwarding based on latency and jitter.

[0013] Further, step 2 includes:

[0014] The first node matches the corresponding service flow based on the source IP address, destination IP address, source port number, destination port number, and protocol number feature information. It adds an outer IPv4 header to the matched service flow so that the first node can find the port. It then completes deterministic forwarding processing based on the specified time slot scheduling, queue number, and bandwidth of the first node. At the same time, after adding the outer IPv4 header, it adds the Segmentation Routing Header field SRH and the Segmentation Routing Operation field SR-OPT.

[0015] Furthermore, in step 2, the message format includes an outer IPv4 header, a segmented routing header field SRH, and a segmented routing operation field SR-OPT;

[0016] The outer IPv4 header has the same format as the ordinary IPv4 header, and the next header protocol type of the message is used to specify whether the information adjacent to the IPv4 header is a deterministic message type.

[0017] The segmented routing header field SRH includes the next header protocol type, total length of the segment list, presence of an operation field, number of remaining segments, total number of segments, and segment list.

[0018] The segmented routing operation field SR-OPT includes a deterministic processing method parameter table DNET; the deterministic processing method parameter table DNET is used to represent the deterministic function-related operations that the data packet passes through sequentially on the network transmission path; the deterministic function-related operations include time slot scheduling, queue numbering, and bandwidth scheduling policies; the time slot scheduling, queue numbering, and bandwidth scheduling policies are used to guide a specified queue to reserve specified bandwidth resources and send the packet out within a specified time range.

[0019] Furthermore, the next header protocol type in the segmented routing header field SRH is used to indicate the message type following the segmented routing header field SRH and the segmented routing operation field SR-OPT;

[0020] The total length of the segment list is used to represent the total length of the segment list fields; the presence or absence of the operation field is used to indicate whether the segment routing operation field SR-OPT is present after the segment routing header field SRH, and the segment routing operation field SR-OPT is used to guide the deterministic forwarding processing method;

[0021] The remaining segment count is used to represent the number of remaining segmented routing segments, i.e., the number of nodes that need to be visited before reaching the destination node, and also represents the index of the segment list and operation field list entries that need to be used at present.

[0022] The total number of segments is used to represent the total number of entries in the entire segment list and operation field list, and also represents the index of the last element in the segment list and operation field list.

[0023] Further, step 3 includes:

[0024] After the first node completes packet encapsulation, it performs forwarding processing within a specified time range and under a specified port queue bandwidth, based on the destination address in the outer IPv4 header and the corresponding time slot scheduling and queue bandwidth scheduling policies.

[0025] Further, step 4 includes:

[0026] Step 41: If the non-first node does not support deterministic forwarding, then forward the service flow according to the destination address in the outer IPv4 header;

[0027] Step 42: If the non-first node supports deterministic forwarding and is a node between the first and last nodes, then based on the deterministic processing method parameter table DNET of the segmented routing operation field SR-OPT and the segment list SID information of the segmented routing header, the destination address of the outer IPv4 header is replaced and the packet is subjected to deterministic forwarding processing; the last node is the last node on the transmission path of the packet from the sender to the receiver.

[0028] Step 43: If it is the tail node, then strip the SRH header field, the SR-OPT segmentation operation field, and the outer IPv4 header of the segmented route inserted into the head node, and perform deterministic forwarding processing according to the deterministic processing method parameter table DNET of the SR-OPT segmentation operation field and the original IPv4 header.

[0029] Further, step 42 includes:

[0030] After receiving the message, the nodes between the first and last nodes process it according to the deterministic processing method parameter table DNET in the Segmented Routing Operation Field (SR-OPT), based on time slot scheduling, queue number, and bandwidth. They also replace and forward the destination address in the outer IPv4 header according to the Segment List SID information in the Segmented Routing Header. The Segment List SID in the Segmented Routing Header Field (SRH) represents the address information of the nodes that need to be traversed on the planned transmission path.

[0031] Step 43 includes:

[0032] After receiving the packet, the tail node records the deterministic parameter table DNET in the segmented routing operation field corresponding to the tail node, deletes all the segmented routing header fields SRH, segmented routing operation field SR-OPT, and outer IPv4 header information inserted into the head node, and performs deterministic forwarding processing according to the recorded deterministic processing method parameter table DNET of the tail node and the original IPv4 header information, based on time slot scheduling, queue number, and bandwidth.

[0033] Furthermore, it also includes:

[0034] If congestion or link failure occurs on the transmission path from the sender to the receiver, the controller replans the path and sends new service information to the first node to achieve deterministic link adjustment and service quality assurance; the new service information includes the segmented routing header SRH and the segmented routing operation field SR-OPT.

[0035] It also includes: if intermediate nodes do not support deterministic forwarding, forwarding is done by looking up the destination address in the outer IPv4 header, with intermediate nodes being the nodes between the head node and the tail node.

[0036] This application also discloses a deterministic forwarding processing apparatus based on an IPv4 network, which implements the aforementioned deterministic forwarding processing method based on an IPv4 network, comprising:

[0037] The service flow information delivery module is used by the controller to deliver service flow information to the first node; the first node is the first node on the transmission path of the packet from the sender to the receiver; the node is a network device with routing and switching functions; the service flow information includes path planning, time slot scheduling, queue bandwidth scheduling, and service flow characteristic strategies.

[0038] The data processing module is used by the first node to match the corresponding service flow according to the service flow feature strategy in the service flow information. It inserts the corresponding outer IPv4 header, Segmentation Routing Header (SRH) field, and Segmentation Routing Operation (SR-OPT) field before the original IPv4 header for the service flow and encapsulates it to obtain a packet. The service flow features include source IP address, destination IP address, source port number, destination port number, and protocol number. The Segmentation Routing Header (SRH) field is a deterministic transmission path field constructed from the sender to the receiver. The Segmentation Routing Operation (SR-OPT) field is a deterministic processing method parameter table (DNET) for the nodes on the transmission path. The deterministic processing method parameter table (DNET) includes time slot scheduling, queue number, and queue bandwidth.

[0039] The processing module is used by the first node to perform deterministic forwarding processing on the packet according to the deterministic processing method parameter table DNET and the destination address in the outer IPv4 header of the packet encapsulated by the data processing module; the deterministic forwarding processing refers to controlling the forwarding time, selecting the forwarding queue, and guaranteeing the bandwidth of the packet according to the deterministic processing method parameter table DNET.

[0040] The judgment module is used to determine whether nodes other than the first node on the transmission path from the sender to the receiver support deterministic forwarding if there is no congestion and no link failure on the transmission path from the sender to the receiver.

[0041] Due to the adoption of the above technical solution, this application has the following advantages:

[0042] 1. This application proposes for the first time a deterministic forwarding mechanism based on IPv4 network bearers. By constructing deterministic forwarding packets compatible with traditional IPv4 forwarding and designing a flexible time-division multiplexing forwarding mechanism, it effectively improves the timeliness and adaptability of network forwarding and has important application prospects in deterministic networks.

[0043] 2. Flat (universal) network deployment enables end-to-end low-latency, low-jitter, and highly reliable network transmission based on time constraints; a flexible and controllable time-division multiplexing forwarding scheduling mechanism effectively improves the utilization rate of scheduling resources; transmission paths are orchestratable and reconfigurable, effectively improving the network's flexible scheduling capabilities; it can interoperate with Layer 3 IPv4 networks, and key nodes provide deterministic forwarding capabilities, effectively improving the overall network reliability transmission.

[0044] 3. Compared to the uncontrollable latency issues of traditional best-effort Ethernet networks, it achieves low-latency, highly deterministic network transmission based on time constraints; compared to other scheduling methods with fixed resource allocation, it implements a flexible and controllable time-division multiplexing forwarding scheduling mechanism; compared to DIP networks based on SRv6, it effectively saves packet transmission space and improves transmission efficiency; compared to the inflexible scheduling of FlexE / TSN / IPv4 networks, it enables network path orchestration and reconfiguration; compared to the inability of FlexE / TSN network protocols to interconnect with Layer 3 IPv4 networks, it can adapt to interoperability with Layer 3 IPv4 networks, achieving deterministic network transmission. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments recorded in the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0046] Figure 1 This is a schematic diagram of a deterministic network layering technique in the prior art;

[0047] Figure 2 This is a schematic diagram of the deterministic forwarding network topology according to an embodiment of this application;

[0048] Figure 3 This is a schematic diagram of data stream latency in an embodiment of this application;

[0049] Figure 4 This is a schematic diagram of flexible time-division multiplexing forwarding scheduling according to an embodiment of this application;

[0050] Figure 5This is a schematic diagram of the time-division multiplexing forwarding scheduling mechanism in an embodiment of this application;

[0051] Figure 6 This is a schematic diagram of the deterministic forwarding process in an embodiment of this application;

[0052] Figure 7 This is a flowchart illustrating a deterministic forwarding method based on an IPv4 network according to an embodiment of this application.

[0053] Figure 8 This is a schematic diagram of the deterministic forwarding message format in an embodiment of this application. Detailed Implementation

[0054] The present application will be further described in conjunction with the accompanying drawings and embodiments. The described embodiments are only some, not all, of the embodiments of the present application. All other embodiments obtained by those skilled in the art should fall within the protection scope of the embodiments of the present application.

[0055] See Figure 7 This application provides an embodiment of a deterministic forwarding processing method based on an IPv4 network, which includes:

[0056] Step 1: The controller sends service flow information to the first node; the first node is the first node on the transmission path of the message from the sender to the receiver; the node is a network device with routing and switching functions; the service flow information includes path planning, time slot scheduling, queue bandwidth scheduling, and service flow characteristic policies.

[0057] Step 2: The first node matches the corresponding service flow according to the service flow feature strategy in the service flow information, inserts the corresponding outer IPv4 header, Segmentation Routing Header (SRH) field, and Segmentation Routing Operation (SR-OPT) field before the original IPv4 header for the service flow, and encapsulates it to obtain a packet; the service flow features include source IP address, destination IP address, source port number, destination port number, and protocol number; the Segmentation Routing Header (SRH) field is a deterministic transmission path field constructed from the sender to the receiver, and the Segmentation Routing Operation (SR-OPT) field is a deterministic processing method parameter table (DNET) of the nodes on the transmission path; the deterministic processing method parameter table (DNET) includes time slot scheduling, queue number, and queue bandwidth;

[0058] Step 3: The first node performs deterministic forwarding processing on the packet according to the deterministic processing method parameter table DNET and the destination address of the outer IPv4 header in the packet encapsulated in Step 2; the deterministic forwarding processing refers to controlling the forwarding time, selecting the forwarding queue, and guaranteeing the bandwidth of the packet according to the deterministic processing method parameter table DNET.

[0059] Step 4: If there is no congestion or link failure on the transmission path from the sender to the receiver, determine whether the nodes on the transmission path from the sender to the receiver, excluding the first node, support deterministic forwarding.

[0060] Optionally, step 1 includes:

[0061] The controller determines the path planning of network nodes and the time slot scheduling, queue number and bandwidth of each node between the first node and the last node according to the network node topology information, network status, service flow characteristics, service flow, bandwidth and latency requirements from the sending end to the receiving end; the path planning is the segment list SID in the segmented route header; the segment list SID is a series of ordered IPv4 network segments, representing the node addresses that the data packet needs to pass through in sequence on the network transmission path; the order of the segment list SID is from back to front, that is, SID[0] represents the address of the last node to be passed through on the planned transmission path; SID[0] is the address of the last node;

[0062] Based on the different service quality requirements of service flows, scheduling queues with different bandwidths are allocated to the service flows. The network device's outgoing port has N queues, and the bandwidth of each queue is D. The bandwidth is not greater than the total bandwidth of the output port. In each transmission cycle T, only one of the N queues is used to send data packets. For the i-th queue, Let be the bandwidth of the i-th queue. This represents the total number of queues at the output ports.

[0063] Under the control of the gating list of network devices, the first queue sends messages in the first transmission cycle; the second queue sends messages in the second transmission cycle; and so on. By sending messages within a specified time range through the queues on each node, the time limit and bandwidth of the message on the entire transmission path are determined, thereby realizing deterministic forwarding based on latency and jitter.

[0064] Optionally, step 2 includes:

[0065] The first node matches the corresponding service flow based on the source IP address, destination IP address, source port number, destination port number, and protocol number feature information. It adds an outer IPv4 header to the matched service flow so that the first node can find the port. It then completes deterministic forwarding processing based on the specified time slot scheduling, queue number, and bandwidth of the first node. At the same time, after adding the outer IPv4 header, it adds the Segmentation Routing Header field SRH and the Segmentation Routing Operation field SR-OPT.

[0066] Optionally, in step 2, the message format includes an outer IPv4 header, a segmented routing header field SRH, and a segmented routing operation field SR-OPT;

[0067] The outer IPv4 header has the same format as the ordinary IPv4 header, and the next header protocol type of the message is used to specify whether the information adjacent to the IPv4 header is a deterministic message type.

[0068] The segmented routing header field SRH includes the next header protocol type, total length of the segment list, presence of an operation field, number of remaining segments, total number of segments, and segment list.

[0069] The segmented routing operation field SR-OPT includes a deterministic processing method parameter table DNET; the deterministic processing method parameter table DNET is used to represent the deterministic function-related operations that the data packet passes through sequentially on the network transmission path; the deterministic function-related operations include time slot scheduling, queue numbering, and bandwidth scheduling policies; the time slot scheduling, queue numbering, and bandwidth scheduling policies are used to guide a specified queue to reserve specified bandwidth resources and send the packet out within a specified time range.

[0070] Optionally, the next header protocol type in the segmented routing header field SRH is used to indicate the message type following the segmented routing header field SRH and the segmented routing operation field SR-OPT;

[0071] The total length of the segment list is used to represent the total length of the segment list fields; the presence or absence of the operation field is used to indicate whether the segment routing operation field SR-OPT is present after the segment routing header field SRH, and the segment routing operation field SR-OPT is used to guide the deterministic forwarding processing method;

[0072] The remaining segment count is used to represent the number of remaining segmented routing segments, i.e., the number of nodes that need to be visited before reaching the destination node, and also represents the index of the segment list and operation field list entries that need to be used at present.

[0073] The total number of segments is used to represent the total number of entries in the entire segment list and operation field list, and also represents the index of the last element in the segment list and operation field list.

[0074] Optionally, step 3 includes:

[0075] After the first node completes packet encapsulation, it performs forwarding processing within a specified time range and under a specified port queue bandwidth, based on the destination address in the outer IPv4 header and the corresponding time slot scheduling and queue bandwidth scheduling policies.

[0076] Optionally, step 4 includes:

[0077] Step 41: If the non-first node does not support deterministic forwarding, then forward the service flow according to the destination address in the outer IPv4 header;

[0078] Step 42: If the non-first node supports deterministic forwarding and is a node between the first and last nodes, then based on the deterministic processing method parameter table DNET of the segmented routing operation field SR-OPT and the segment list SID information of the segmented routing header, the destination address of the outer IPv4 header is replaced and the packet is subjected to deterministic forwarding processing; the last node is the last node on the transmission path of the packet from the sender to the receiver.

[0079] Step 43: If it is the tail node, then strip the SRH header field, the SR-OPT segmentation operation field, and the outer IPv4 header of the segmented route inserted into the head node, and perform deterministic forwarding processing according to the deterministic processing method parameter table DNET of the SR-OPT segmentation operation field and the original IPv4 header.

[0080] Optionally, step 42 includes:

[0081] After receiving the message, the nodes between the first and last nodes process it according to the deterministic processing method parameter table DNET in the Segmented Routing Operation Field (SR-OPT), based on time slot scheduling, queue number, and bandwidth. They also replace and forward the destination address in the outer IPv4 header according to the Segment List SID information in the Segmented Routing Header. The Segment List SID in the Segmented Routing Header Field (SRH) represents the address information of the nodes that need to be traversed on the planned transmission path.

[0082] Step 43 includes:

[0083] After receiving the packet, the tail node records the deterministic parameter table DNET in the segmented routing operation field corresponding to the tail node, deletes all the segmented routing header fields SRH, segmented routing operation field SR-OPT, and outer IPv4 header information inserted into the head node, and performs deterministic forwarding processing according to the recorded deterministic processing method parameter table DNET of the tail node and the original IPv4 header information, based on time slot scheduling, queue number, and bandwidth.

[0084] Optionally, it also includes:

[0085] If congestion or link failure occurs on the transmission path from the sender to the receiver, the controller replans the path and sends new service information to the first node to achieve deterministic link adjustment and service quality assurance; the new service information includes the segmented routing header SRH and the segmented routing operation field SR-OPT.

[0086] It also includes: if intermediate nodes do not support deterministic forwarding, forwarding is done by looking up the destination address in the outer IPv4 header, with intermediate nodes being the nodes between the head node and the tail node.

[0087] For ease of understanding, this application also provides a more specific embodiment:

[0088] See Figure 2 In traditional best-effort networks, a long-tail latency phenomenon exists, typically requiring the dropping of more packets at the tail to achieve lower latency. However, deterministic forwarding aims to solve this long-tail problem by providing bounded latency. Deterministic forwarding requires that the worst-case latency be bounded, meaning that under conditions of flow bursts or congestion, the maximum end-to-end latency of the flow does not exceed a certain value; it also satisfies low latency, meaning that the worst-case latency is as close as possible to the minimum latency, thereby reducing latency variations (jitter). Figure 3 As shown.

[0089] Following the periodic queuing and forwarding mechanism proposed by the IETF DetNet Working Group, this application designs a deterministic forwarding method for data latency and jitter applicable to Layer 3 IPv4 networks.

[0090] Forwarding mechanisms based on time-sliced ​​round-robin scheduling, such as Figure 4 As shown, from the perspective of a single device, this mechanism can allocate scheduling queues with different bandwidths to service flows according to different service quality requirements. The transmission period is T (configurable, in units of 1µs), the transmission time slot interval (referred to as time slot) is K (configurable, a divisor of the transmission period), and the total number of scheduling queues is N (configurable, N ranges from 2 to 32). That is, the device's output port has N queues. In each transmission period T, only one queue can send out data packets, while the other queues are used to put data packets into the queue for future transmission.

[0091] Under the control of the device's sending gating list, in the first transmission cycle, scheduling queue 1 sends the data packets in its queue; in the second transmission cycle, scheduling queue 2 sends the data packets in its queue; and so on, sending in a cyclical manner. By having the scheduling queues on each node send the packets out within a specified time range, the time limit for the packet along the entire path is guaranteed, achieving deterministic forwarding based on latency and jitter. A schematic diagram of the elastic time-division multiplexing forwarding scheduling is shown below. Figure 4 As shown.

[0092] Taking a time-division multiplexing forwarding scheduling mechanism with 4 nodes (ABCD) as an example, such as Figure 5 As shown in the diagram, on node A, the service flow is scheduled to be sent in the next cycle of the receive cycle; on node B, the service flow is scheduled to be sent in the last two cycles of the receive cycle; and on node C, the service flow is scheduled to be transmitted in the last three cycles of the receive cycle. In this way, the service flow transmission delay on the four nodes is controlled within 5 to 7 cycles.

[0093] From the above analysis, we can deduce that, assuming a flow's planned forwarding path passes through X nodes, the path hop count is H, the transmission period is set to T, and the transmission time slot interval set for each node is... Then the shortest and longest delays of this stream are respectively:

[0094]

[0095]

[0096] in, and These are the shortest and longest delays for the stream, respectively.

[0097] End-to-end latency jitter for:

[0098]

[0099] Based on the segmented routing protocol mechanism, forwarding control information of data packets is carried in the packet header information. The packet header information is used to guide the forwarding behavior of data packets at nodes along the path, providing support for services to achieve deterministic forwarding at the network layer.

[0100] Following the Layer 3 header of an Ethernet IPv4 packet, a series of ordered lists of segmented routes are inserted to guide packet forwarding at nodes. The information contained in the segmented route includes the Segment Routing Header (SRH) field and the Segment Routing Operation Header (SR-OPT) field. The SRH field is essential information; it uses a series of segment IDs (SIDs) to plan the forwarding path. This ordered set of SIDs is called the Segment List. Simultaneously, the Segment Routing Operation Header field guides controlled packet forwarding. The specific packet format is as follows: Figure 8 As shown.

[0101] The next header protocol type in the outer IPv4 header is 8 bits long, and the deterministic message type is 0xF1.

[0102] The meanings of each part of the SRH field in the segmented routing header are defined as follows:

[0103] (1) Next header protocol type: 8 bits long, used to indicate the protocol type that follows SRH+SR-OPT.

[0104] (2) Total length of segment list: 7 bits long, used to represent the total length of segment list fields.

[0105] (3) Whether there is an operation field: 1 bit long, used to indicate whether there is any related operation information after SRH, and used to guide the forwarding processing method.

[0106] (4) Number of remaining segments: 8 bits long, used to represent the number of remaining routing segments, that is, the number of nodes that should be visited before reaching the destination node. This value specifies the segment list and operation field list entry index that should be used at the moment.

[0107] (5) Total number of segments: 8 bits long, used to represent the total number of entries in the entire segment list and operation field list. This value specifies the index of the last element in the segment list and operation field list.

[0108] (6) Segment list: Variable length, is a series of ordered IPv4 network segments, representing the node addresses that a data packet needs to pass through in sequence on the network transmission path. The order of the segment list is from back to front, that is, SID[0] represents the address of the last node that needs to be passed through on the planned transmission path.

[0109] The meanings of each part of the segmented routing operation field are defined as follows:

[0110] (1) Deterministic processing method parameter table: Variable length, is an operation function field composed of a series of ordered deterministic processing method parameters, which represent the deterministic function-related operations of the data packet on the nodes it passes through in sequence on the network transmission path, such as the time slot queue scheduling strategy, which guides the time slot queue to forward the packet. The order of the entries is from back to front, that is, DNET[0] represents the operation required by the last node on the planned transmission path.

[0111] (2) Deterministic forwarding process

[0112] The deterministic forwarding process in this application is based on the inter-node link connectivity, information reachability, and time synchronization. By controlling the packet sending time of each node, the upper bound of the end-to-end latency for each flow through the network system is obtained, thereby planning a reasonable scheduling method and forwarding path that meets the latency upper bound requirement for each service flow. See also Figure 6 The main processing steps are as follows:

[0113] Based on network resource availability, forwarding path 1 is planned and controlled:

[0114] 1) The controller sends business flow characteristics, path planning (node ​​1, node 2, node 3, node 4), time slot scheduling, queue bandwidth scheduling and other strategies to the first node (node ​​1).

[0115] 2) After receiving the configuration, the first node (node ​​1) matches the service flow feature information, inserts the corresponding outer IPv4 header, segmented routing header field SRH, and segmented routing operation field SR-OPT before the original IPv4 header for the service, and encapsulates it to obtain a packet, thus constructing a definite forwarding path.

[0116] 3) After the first node (node ​​1) completes the packet encapsulation, it finds the outgoing interface based on the outer IPv4 header information and forwards the packet out according to the corresponding time slot queue based on the DNET information.

[0117] 4) After receiving the message, the intermediate nodes (node ​​2 and node 3) find the outgoing interface according to the corresponding SID information in the segmented routing header field, and forward the message according to the corresponding time slot queue according to the DNET information.

[0118] 5) After receiving the packet, the tail node (node ​​4) records the corresponding SID and DNET information, strips all the outer IPv4 header, fragment routing header field, and fragment routing operation field information inserted by the head node, finds the outgoing interface based on the recorded SID information, and forwards the packet out according to the corresponding time slot queue based on the DNET information.

[0119] This completes the deterministic forwarding process for the service, ensuring that the service reaches its destination within the planned timeframe.

[0120] When congestion or link failure occurs at node 2 or node 3 in forwarding path 1, the controller can replan the forwarding path (node ​​1, node 5, node 6, node 4) to achieve flexible orchestration and reconstruction of the forwarding path. The specific processing flow is the same as that of planned path 1.

[0121] When some intermediate nodes in the forwarding path do not support the segmented routing forwarding method designed in this application, table lookup forwarding can be performed according to the Layer 3 IPv4 network to achieve compatibility and interoperability with the Layer 3 IPv4 network.

[0122] This application also provides an embodiment of a deterministic forwarding processing apparatus based on an IPv4 network, which implements the deterministic forwarding processing method based on an IPv4 network described in the above embodiments, and includes:

[0123] The service flow information delivery module is used by the controller to deliver service flow information to the first node; the first node is the first node on the transmission path of the packet from the sender to the receiver; the node is a network device with routing and switching functions; the service flow information includes path planning, time slot scheduling, queue bandwidth scheduling, and service flow characteristic strategies.

[0124] The data processing module is used by the first node to match the corresponding service flow according to the service flow feature strategy in the service flow information. It inserts the corresponding outer IPv4 header, Segmentation Routing Header (SRH) field, and Segmentation Routing Operation (SR-OPT) field before the original IPv4 header for the service flow and encapsulates it to obtain a packet. The service flow features include source IP address, destination IP address, source port number, destination port number, and protocol number. The Segmentation Routing Header (SRH) field is a deterministic transmission path field constructed from the sender to the receiver. The Segmentation Routing Operation (SR-OPT) field is a deterministic processing method parameter table (DNET) for the nodes on the transmission path. The deterministic processing method parameter table (DNET) includes time slot scheduling, queue number, and queue bandwidth.

[0125] The processing module is used by the first node to perform deterministic forwarding processing on the packet according to the deterministic processing method parameter table DNET and the destination address in the outer IPv4 header of the packet encapsulated by the data processing module; the deterministic forwarding processing refers to controlling the forwarding time, selecting the forwarding queue, and guaranteeing the bandwidth of the packet according to the deterministic processing method parameter table DNET.

[0126] The judgment module is used to determine whether nodes other than the first node on the transmission path from the sender to the receiver support deterministic forwarding if there is no congestion and no link failure on the transmission path from the sender to the receiver.

[0127] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and not to limit them. Although this application has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of this application. Any modifications or equivalent substitutions that do not depart from the spirit and scope of this application should be covered within the protection scope of the claims of this application.

Claims

1. A method for deterministic forwarding treatment based on an IPv4 network, characterized in that, include: Step 1: The controller sends service flow information to the first node; the first node is the first node on the transmission path of the message from the sender to the receiver; the node is a network device with routing and switching functions; the service flow information includes path planning, time slot scheduling, queue bandwidth scheduling, and service flow characteristic policies. Step 2: The first node matches the corresponding service flow according to the service flow feature strategy in the service flow information, inserts the corresponding outer IPv4 header, Segmentation Routing Header (SRH) field, and Segmentation Routing Operation (SR-OPT) field before the original IPv4 header for the service flow, and encapsulates it to obtain a packet; the service flow features include source IP address, destination IP address, source port number, destination port number, and protocol number; the Segmentation Routing Header (SRH) field is a deterministic transmission path field constructed from the sender to the receiver, and the Segmentation Routing Operation (SR-OPT) field is a deterministic processing method parameter table (DNET) of the nodes on the transmission path; the deterministic processing method parameter table (DNET) includes time slot scheduling, queue number, and queue bandwidth; Step 3: The first node performs deterministic forwarding processing on the packet based on the deterministic processing method parameter table DNET and the destination address of the outer IPv4 header in the packet encapsulated in Step 2; The deterministic forwarding process refers to controlling the forwarding time, selecting the forwarding queue, and guaranteeing the bandwidth of the packet according to the deterministic processing method parameter table DNET. Step 4: If there is no congestion or link failure on the transmission path from the sender to the receiver, determine whether the nodes on the transmission path from the sender to the receiver, excluding the first node, support deterministic forwarding. Step 1 includes: The controller determines the path planning of network nodes and the time slot scheduling, queue number and bandwidth of each node between the first node and the last node according to the network node topology information, network status, service flow characteristics, service flow, bandwidth and latency requirements from the sending end to the receiving end; the path planning is the segment list SID in the segmented route header; the segment list SID is a series of ordered IPv4 network segments, representing the node addresses that the data packet needs to pass through in sequence on the network transmission path; the order of the segment list SID is from back to front, that is, SID[0] represents the address of the last node to be passed through on the planned transmission path; SID[0] is the address of the last node; Based on the different service quality requirements of service flows, scheduling queues with different bandwidths are allocated to the service flows. The network device's outgoing port has N queues, and the bandwidth of each queue is D. The bandwidth is not greater than the total bandwidth of the output port. In each transmission cycle T, only one of the N queues is used to send data packets. For the i-th queue, Let be the bandwidth of the i-th queue. This represents the total number of queues at the output ports. Under the control of the gating list of network devices, the first queue sends messages in the first transmission cycle; the second queue sends messages in the second transmission cycle; and so on. By sending messages within a specified time range through the queues on each node, the time limit and bandwidth of the message on the entire transmission path are determined, thereby realizing deterministic forwarding based on latency and jitter.

2. The deterministic forwarding processing method based on IPv4 networks according to claim 1, characterized in that, Step 2 includes: The first node matches the corresponding service flow based on the source IP address, destination IP address, source port number, destination port number, and protocol number feature information. It adds an outer IPv4 header to the matched service flow so that the first node can find the port. It then completes deterministic forwarding processing based on the specified time slot scheduling, queue number, and bandwidth of the first node. At the same time, after adding the outer IPv4 header, it adds the Segmentation Routing Header field SRH and the Segmentation Routing Operation field SR-OPT.

3. The deterministic forwarding processing method based on IPv4 networks according to claim 1, characterized in that, In step 2, the message format includes an outer IPv4 header, a Segmentation Routing Header field (SRH), and a Segmentation Routing Operation field (SR-OPT). The outer IPv4 header has the same format as the ordinary IPv4 header, and the next header protocol type of the message is used to specify whether the information adjacent to the IPv4 header is a deterministic message type. The segmented routing header field SRH includes the next header protocol type, total length of the segment list, presence of an operation field, number of remaining segments, total number of segments, and segment list. The segmented routing operation field SR-OPT includes a deterministic processing method parameter table DNET; the deterministic processing method parameter table DNET is used to represent the deterministic function-related operations that the data packet passes through sequentially on the network transmission path; the deterministic function-related operations include time slot scheduling, queue numbering, and bandwidth scheduling policies; the time slot scheduling, queue numbering, and bandwidth scheduling policies are used to guide a specified queue to reserve specified bandwidth resources and send the packet out within a specified time range.

4. The deterministic forwarding processing method based on IPv4 networks according to claim 3, characterized in that, The next header protocol type in the Segmented Routing Header field SRH is used to indicate the message type following the Segmented Routing Header field SRH and the Segmented Routing Operation field SR-OPT. The total length of the segment list is used to represent the total length of the segment list fields; the presence or absence of the operation field is used to indicate whether the segment routing operation field SR-OPT is present after the segment routing header field SRH, and the segment routing operation field SR-OPT is used to guide the deterministic forwarding processing method; The remaining segment count is used to represent the number of remaining segmented routing segments, i.e., the number of nodes that need to be visited before reaching the destination node, and also represents the index of the segment list and operation field list entries that need to be used at present. The total number of segments is used to represent the total number of entries in the entire segment list and operation field list, and also represents the index of the last element in the segment list and operation field list.

5. The deterministic forwarding processing method based on IPv4 networks according to claim 1, characterized in that, Step 3 includes: After the first node completes packet encapsulation, it performs forwarding processing within a specified time range and under a specified port queue bandwidth, based on the destination address in the outer IPv4 header and the corresponding time slot scheduling and queue bandwidth scheduling policies.

6. The deterministic forwarding processing method based on IPv4 networks according to claim 1, characterized in that, Step 4 includes: Step 41: If the non-first node does not support deterministic forwarding, then forward the service flow according to the destination address in the outer IPv4 header; Step 42: If the non-first node supports deterministic forwarding and is a node between the first and last nodes, then based on the deterministic processing method parameter table DNET of the segmented routing operation field SR-OPT and the segment list SID information of the segmented routing header, the destination address of the outer IPv4 header is replaced and the packet is subjected to deterministic forwarding processing; the last node is the last node on the transmission path of the packet from the sender to the receiver. Step 43: If it is the tail node, then strip the SRH header field, the SR-OPT segmentation operation field, and the outer IPv4 header of the segmented route inserted into the head node, and perform deterministic forwarding processing according to the deterministic processing method parameter table DNET of the SR-OPT segmentation operation field and the original IPv4 header.

7. The deterministic forwarding processing method based on IPv4 networks according to claim 6, characterized in that, Step 42 includes: After receiving the message, the nodes between the first and last nodes process it according to the deterministic processing method parameter table DNET in the Segmented Routing Operation Field (SR-OPT), based on time slot scheduling, queue number, and bandwidth. They also replace and forward the destination address in the outer IPv4 header according to the Segment List SID information in the Segmented Routing Header. The Segment List SID in the Segmented Routing Header Field (SRH) represents the address information of the nodes that need to be traversed on the planned transmission path. Step 43 includes: After receiving the packet, the tail node records the deterministic parameter table DNET in the segmented routing operation field corresponding to the tail node, deletes all the segmented routing header fields SRH, segmented routing operation field SR-OPT, and outer IPv4 header information inserted into the head node, and performs deterministic forwarding processing according to the recorded deterministic processing method parameter table DNET of the tail node and the original IPv4 header information, based on time slot scheduling, queue number, and bandwidth.

8. The deterministic forwarding processing method based on IPv4 networks according to claim 1, characterized in that, Also includes: If congestion or link failure occurs on the transmission path from the sender to the receiver, the controller replans the path and sends new service information to the first node, thereby achieving deterministic link adjustment and service quality assurance. The new service information includes the segmented routing header SRH and the segmented routing operation field SR-OPT; It also includes: if intermediate nodes do not support deterministic forwarding, then forwarding is done by looking up the destination address in the outer IPv4 header; The intermediate node is the node between the first node and the last node.

9. A deterministic forwarding processing apparatus based on an IPv4 network, implementing the deterministic forwarding processing method based on an IPv4 network as described in any one of claims 1-8, characterized in that, include: The service flow information delivery module is used by the controller to deliver service flow information to the first node; the first node is the first node on the transmission path of the packet from the sender to the receiver; the node is a network device with routing and switching functions; the service flow information includes path planning, time slot scheduling, queue bandwidth scheduling, and service flow characteristic strategies. The data processing module is used by the first node to match the corresponding service flow according to the service flow feature strategy in the service flow information. It inserts the corresponding outer IPv4 header, Segmentation Routing Header (SRH) field, and Segmentation Routing Operation (SR-OPT) field before the original IPv4 header for the service flow and encapsulates it to obtain a packet. The service flow features include source IP address, destination IP address, source port number, destination port number, and protocol number. The Segmentation Routing Header (SRH) field is a deterministic transmission path field constructed from the sender to the receiver. The Segmentation Routing Operation (SR-OPT) field is a deterministic processing method parameter table (DNET) for the nodes on the transmission path. The deterministic processing method parameter table (DNET) includes time slot scheduling, queue number, and queue bandwidth. The processing module is used by the first node to perform deterministic forwarding processing on the packet based on the deterministic processing method parameter table DNET and the destination address in the outer IPv4 header of the packet encapsulated by the data processing module; The deterministic forwarding process refers to controlling the forwarding time, selecting the forwarding queue, and guaranteeing the bandwidth of the packet according to the deterministic processing method parameter table DNET. The judgment module is used to determine whether nodes other than the first node on the transmission path from the sender to the receiver support deterministic forwarding if there is no congestion and no link failure on the transmission path from the sender to the receiver.

Images