Cross-domain traffic deterministic delay transmission method and system

Abstract

The invention provides a cross-domain traffic deterministic time delay transmission method and system, WRAS is deployed in each AS domain, information sharing is carried out among the AS domains by using a block chain, routing calculation is carried out on deterministic traffic in a source AS domain to generate a global path, routing calculation is carried out on a transmission path of the deterministic traffic in the domain in other AS domains, and the global path is generated. And finally, the flow is transmitted according to the determined path. According to the invention, distributed management of cross-domain traffic transmission is realized, and the problem that accurate routing information is difficult to obtain due to the lack of a trust mechanism among AS domains in the existing wide area network is effectively solved; therefore, end-to-end deterministic traffic transmission across the AS domain is effectively realized.

Description

Technical Field

[0001] This invention belongs to the field of future network technology, specifically relating to a method and system for deterministic delay transmission of cross-domain traffic. Background Technology

[0002] Traditional IP network data transmission is typically based on a "best-effort" model, meaning the network transmits data as much as possible but does not guarantee Quality of Service (QoS) metrics such as latency, jitter, and packet loss rate. However, with the development of emerging applications (such as industrial internet, autonomous driving, and financial transactions), higher demands are placed on the determinism of network transmission QoS, especially latency. These services are often referred to as time-sensitive traffic, requiring deterministic latency boundaries. Deterministic Networking (DetNet) aims to provide end-to-end deterministic QoS traffic (hereinafter referred to as "deterministic traffic") transmission services for IP networks. It introduces time-aware scheduling and resource reservation mechanisms into IP networks to ensure that critical traffic obtains deterministic transmission paths and resources. Simultaneously, it employs techniques such as time synchronization, time slot mapping, and traffic shaping to control latency boundaries, suppress jitter and packet loss, and achieve deterministic QoS transmission of traffic. Deterministic Networking is widely considered an important technology for the future of networking, and significant progress has been made in the development of deterministic network standards, the development of prototypes, and pilot projects for small-scale networking applications (in industries such as industry and power).

[0003] With the continuous development of network applications, the demand for deterministic traffic transmission in wide area networks (WANs) is increasing. Achieving deterministic traffic transmission in complex network environments spanning multiple Autonomous System (AS) domains presents numerous challenges. Existing DetNet-related technologies require comprehensive updates to hardware infrastructure and complex configuration processes, which pose significant difficulties in large-scale WAN deployments. While existing lightweight deterministic frameworks based on route-aware shapers (RAS) alleviate deployment challenges to some extent, they still have significant shortcomings in cross-domain WAN scenarios. For example, they struggle to effectively handle the complex and ever-changing routing environment in WANs, coordination issues between different AS domains, and large-scale traffic bursts.

[0004] In cross-domain scenarios, different AS domains are operated by different management organizations, and their network topologies, routing policies, and traffic characteristics vary. When deterministic traffic needs to be transmitted across multiple AS domains, the RAS method faces difficulties in obtaining accurate and real-time routing information because the routing information of each AS domain may have issues such as privacy protection and untimely updates. Simultaneously, the lack of an effective trust mechanism between different AS domains makes it difficult to coordinate RAS scheduling decisions across domains, easily leading to traffic conflicts and unstable latency. Furthermore, traffic bursts in WANs have a larger scale and greater uncertainty; existing RAS methods may not be able to maintain the low latency and high reliability requirements of deterministic traffic when controlling such large-scale bursts. Therefore, addressing the issue of WAN-aware cross-AS routing and establishing mutual trust in the deterministic QoS guarantee capabilities of each AS domain, enabling it to adapt to providing end-to-end deterministic traffic transmission across multiple AS domains, is an urgent problem to be solved. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method and system for deterministic delay transmission of cross-domain traffic, which solves the problem of end-to-end deterministic traffic transmission across AS domains.

[0006] The present invention achieves the above-mentioned technical objectives through the following technical means.

[0007] A deterministic delay transmission method for cross-domain traffic, for deterministic traffic transmitted across domains:

[0008] Within the source AS domain, route calculations are performed for deterministic traffic, generating a global path from the source DES to the target DES, and traffic characteristic descriptions and demand information are sent to other AS domains.

[0009] For other routes passing through the AS domain, route calculations are performed for the transmission path of deterministic traffic within this domain, and feedback is given on whether the deterministic traffic can be accepted based on the calculation results;

[0010] If all AS domains can accept the traffic, then the deterministic traffic is transmitted along the path determined in the above manner.

[0011] Furthermore, information is shared between the various AS domains via blockchain, including:

[0012] Each AS domain uploads the routing, topology, bandwidth, latency, and available resource information of nodes and links that support deterministic latency forwarding within its domain, as well as the latency upper bound of BR nodes and the latency upper bound of inter-domain links between neighboring BRs and its own BRs, to the blockchain network.

[0013] Within the source AS domain, global path routing calculations are performed based on shared information, and traffic characteristic descriptions and demand information are uploaded to the blockchain network;

[0014] If there exists an intra-domain path with deterministic delay forwarding within each AS domain, the acceptable intention and the corresponding intra-domain path's delay upper bound will be uploaded to the blockchain network.

[0015] Furthermore, the routing calculation is as follows: with the goal of minimizing the upper bound of latency, and with the constraint that the available resources for each process are greater than or equal to the resources required for deterministic traffic;

[0016] Within each AS domain, after route calculation, resource reservation is initiated according to the deterministic traffic transmission path within the domain.

[0017] Furthermore, each AS domain performs traffic shaping and traffic scheduling on the deterministic traffic transmitted within the domain.

[0018] Furthermore, the traffic scheduling includes:

[0019] Traffic orchestration among multiple deterministic traffic streams: Based on the traffic characteristics description of the deterministic traffic streams, calculate the number of buffer queues occupied by the stream, select the buffer queue sequence number for the deterministic traffic streams, and distribute the multiple deterministic traffic streams carried on the same link for transmission in different time units;

[0020] Integrated scheduling among multiple deterministic traffic flows: bandwidth is reserved for deterministic traffic. The difference between the interface bandwidth and the total reserved bandwidth for all deterministic flows currently being served is used for scheduling nondeterministic traffic.

[0021] Furthermore, the traffic shaping is as follows: based on the deterministic traffic characteristic description, a hybrid model of token bucket and leaky bucket is used to configure shaping parameters; wherein, the token bucket rate is set at α% of the minimum bottleneck link bandwidth, and the leaky bucket capacity is set at the maximum transmission unit (MTU) * maximum burst length * coefficient β.

[0022] A deterministic delay transmission system for cross-domain traffic:

[0023] Each AS domain has a WRAS deployed, which is responsible for performing route calculations for deterministic traffic and for traffic shaping and scheduling during traffic transmission.

[0024] The blockchain network is jointly maintained by blockchain nodes set up in each AS domain and is used to share information for WRAS in each AS domain.

[0025] Based on the aforementioned cross-domain traffic deterministic delay transmission method, deterministic traffic is transmitted.

[0026] Furthermore, the WRAS is deployed on the ingress router where deterministic traffic enters the AS domain, including:

[0027] Deploy WRAS at the PE router connected to DES to perform global route calculations for deterministic traffic from DES within the domain to DES outside the domain, and to shape and schedule deterministic traffic within the domain.

[0028] Deploy WRAS at the BR router at the entry point of each AS domain to respond to the source domain, formulate the actual transmission path of deterministic traffic within the domain, and shape and schedule deterministic traffic from adjacent AS domains.

[0029] Furthermore, within each AS domain, a secure communication channel is established between WRAS and the blockchain nodes.

[0030] Furthermore, the WRAS is also responsible for actively performing performance testing on links, nodes, or subnets, including latency and packet loss; the testing methods are active measurement, passive measurement, or a combination of both.

[0031] The beneficial effects of this invention are as follows:

[0032] (1) This invention provides a method and system for deterministic delay transmission of cross-domain traffic. By deploying WRAS in each AS domain and sharing information between them using blockchain, a distributed management of cross-domain traffic transmission is realized, which effectively overcomes the problem that there is a lack of trust mechanism between AS domains in the existing wide area network and it is difficult to obtain accurate routing information; thus, end-to-end deterministic traffic transmission across AS domains is effectively realized.

[0033] (2) This invention can reduce the construction and maintenance costs of wide area deterministic networks. Based on the existing wide area network infrastructure, this invention only requires adding a WRAS functional entity to the software and introducing blockchain technology to realize cross-domain wide area deterministic traffic transmission. In particular, it does not require hardware replacement and complex configuration of the P router, which accounts for a large proportion of the existing network cost. Furthermore, the technical solution of this invention has good scalability, so the cost of network transformation, construction and maintenance is relatively low.

[0034] (3) This invention breaks through the routing awareness boundary of a single network domain based on blockchain technology. Compared with the original RAS routing awareness, which only targets internal links and routing paths within the domain and is used to control the burst characteristics of traffic aggregation within the domain, this invention extends routing awareness to wide area network cross-AS domain scenarios. It can obtain and utilize information such as the status of inter-domain links, resource capacity of each AS domain, and routing policies in cross-domain routing in real time, and coordinate and constrain traffic transmission modes among multiple autonomous systems.

[0035] (4) This invention shares routing information of each AS domain through blockchain, thereby obtaining more comprehensive and accurate information when selecting cross-domain routes, thereby generating the optimal transmission path, reducing delays and packet loss caused by unreasonable routing, and improving the efficiency of deterministic traffic transmission. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of a cross-domain wide area network and its traffic transmission system in an embodiment of this application;

[0037] Figure 2 This is a schematic diagram of the router with WRAS deployed according to the present invention. Detailed Implementation

[0038] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0039] I. Cross-domain wide area network

[0040] like Figure 1 The cross-domain wide area network shown consists of multiple AS domains, each AS domain containing multiple deterministic terminal systems (DES) and network nodes, wherein:

[0041] DES is a host device located at the network edge responsible for generating and processing data (i.e., generating and terminating deterministic traffic), and is connected to PE routers in the network.

[0042] Network nodes consist of routing devices such as edge routers (PE), backbone routers (P), and border routers (BR); among them, PE routers are connected to DES and are used to connect DES to the network; P routers are located in the network center and are responsible for traffic forwarding; BR routers are responsible for connecting different AS domains.

[0043] Each network node is connected by a link. Links connecting nodes within the same AS domain are called internal links, and links connecting BR routers between different AS domains are called inter-domain links.

[0044] For the aforementioned cross-domain wide area networks, the following cross-domain traffic deterministic delay transmission system is constructed:

[0045] 1) Each AS domain shall be configured with at least one Wide Area Route Aware Shaper (WRAS) to select the optimal cross-domain transmission path for deterministic traffic from DES within the domain to DES outside the domain, and to schedule and shape the deterministic traffic.

[0046] The core function of WRAS is to control traffic sent from the ingress link to internal network links, and to prevent packets of the same type of traffic from flooding the same internal link through traffic orchestration (a part of traffic scheduling). Therefore, the WRAS functional entity is deployed on the ingress router of deterministic traffic entering the AS domain. Specifically: ① Within an AS domain (such as an IP metropolitan area network built by a single operator), the WRAS functional entity is deployed at the PE router connected to the DES. It is used to perform global route calculations to select the optimal cross-domain path for deterministic traffic sent from the DES within the domain to the DES outside the domain, and to shape and schedule the deterministic traffic within the domain; ② Between AS domains, the WRAS functional entity is deployed at the BR router at the ingress of each AS domain. It is used to respond to the source domain, orchestrate the actual transmission path of deterministic traffic within the domain, and to shape and schedule deterministic traffic from adjacent AS domains to adapt to the forwarding mechanism of the data plane of the AS domain, thereby forwarding the traffic to the next AS domain or the target DES according to the promised delay boundary.

[0047] 2) Information is shared among AS domains via blockchain, including but not limited to routing information, topology information, latency information, available resource information, upper bounds of inter-domain link latency, and upper bounds of BR router latency. The blockchain is jointly maintained by all AS domains. Each AS domain selects a reliable node with stable network connectivity as the blockchain node, responsible for collecting the above information and uploading it to the blockchain in encrypted form.

[0048] Within each AS domain, WRAS establishes a secure communication channel with the blockchain nodes, employing encryption technology to ensure the security and privacy of data during transmission, such as using SSL / TLS encryption protocols to establish communication connections between WRAS and the blockchain nodes.

[0049] II. Deterministic Delay Transmission of Cross-Domain Traffic

[0050] 1. Deterministic traffic cross-domain transmission process

[0051] Reference Figure 1 As shown, the example illustrates the transmission of deterministic traffic from DES-1 in AS100 to DES-2 in AS400. AS100 is the source domain, AS400 is the destination domain, and the AS domains transmitting traffic between AS100 and AS400 are intermediate domains. Deterministic traffic flows from the source domain through several (zero to more) intermediate domains into the destination domain, where:

[0052] 1) Within the source domain AS100, the deterministic traffic generated by DES-1 is shaped at the PE router's ingress interface under the control of the WRAS (at the PE router), and then forwarded to the next-hop P router at the PE router's egress interface within the scheduled time unit. After being relayed by several P routers, it reaches the BR router to be sent to the next AS domain (intermediate domain or destination domain).

[0053] 2) Within the intermediate domain, deterministic traffic flows into the BR router from the inter-domain link under the control of the WRAS at the ingress BR router, and then is relayed by several P routers within the domain to reach another BR router to be sent to the next AS domain (intermediate domain or destination domain).

[0054] 3) Within the target domain AS400, deterministic traffic flows into the BR router from the inter-domain link under the control of the WRAS at the ingress BR router, and is then forwarded by several P routers within the domain, reaching the PE router connected to DES-2, and finally being received by DES-2.

[0055] 2. Wide Area Route Aware Shaper (WRAS)

[0056] like Figure 2 As shown, the WRAS functional entity can be directly integrated into existing router devices. The router device runs the WRAS function program to perform tasks including: wide-area route awareness, end-to-end route calculation, shaping parameter setting, and traffic orchestration. Thus, during deterministic, time-delayed cross-domain traffic transmission, it performs end-to-end route calculation based on routing information, topology information, delay information, and available resource information to obtain the optimal deterministic traffic transmission path; and during traffic transmission, it is responsible for traffic shaping and traffic scheduling.

[0057] 2.1 Wide Area Router Awareness

[0058] The WRAS functional entity connects to the blockchain nodes within the domain through the first communication interface to obtain information on routing, topology, latency, and available resources of other AS domains, as well as the upper bound of inter-domain link latency and the upper bound of BR router latency.

[0059] 2.2 End-to-end route calculation

[0060] Based on the information obtained above, such as the global topology, latency upper bound, and available resources, an end-to-end deterministic transmission path is calculated for deterministic traffic, i.e., route calculation. In actual hardware settings, the WRAS functional entity can either perform route calculation itself or connect to an external path calculation unit through a third communication interface to request the external path calculation unit to perform route calculation and return the calculation result.

[0061] For the source domain, routing computation calculates the global path from the source DES to the destination DES. Therefore, the objective is to minimize the upper bound of the delay from the source DES (i.e., the DES that generates deterministic traffic) to the destination DES (i.e., the DES that receives deterministic traffic), and the constraint is that the available resources in each path are greater than or equal to the resources required for deterministic traffic. The optimal cross-domain path is then calculated. These available resources include: ① the available transmission resources of the set of nodes and links within the domain that support deterministic traffic transmission, and ② the resources available for transmitting deterministic traffic in the links between domains.

[0062] The transmission paths calculated by the source domain WRAS above are only coarse for transmission paths through other domains, except for paths within the source domain (because the information shared by external AS domains may be virtual links). More detailed route calculations are needed from the WRAS of each of the other domains for the actual transmission paths within their respective domains.

[0063] For the intermediate domain, the routing calculation is performed with the goal of minimizing the upper bound of the delay between the BR router that inputs deterministic traffic and the BR router that outputs deterministic traffic within the domain.

[0064] For the target domain, the routing calculation is performed with the goal of minimizing the upper bound of the delay between the BR router (within this domain) and the target DES (within this domain) that handles deterministic traffic.

[0065] For example, the following routing calculation method can be used: First, prune links in the links that support deterministic traffic transmission where the available resources are less than the resources required for deterministic traffic; for the pruned topology, use the upper bound of intra-domain node delay, the upper bound of intra-domain link delay or virtual link delay, the upper bound of inter-domain BR router node delay, and the upper bound of inter-domain link delay as metrics (i.e., metric values ​​in routing calculation), and use the CSPF algorithm to calculate the path with the minimum upper bound of delay from the source DES to the target DES.

[0066] Within each AS domain, after route calculation, WRAS initiates resource reservation based on the deterministic traffic transmission path within its domain. This involves: WRAS initiating a request to lock forwarding path resources to the resource management unit within its domain via a second communication interface, receiving feedback on resource reservation success or failure (including the reason for failure), and periodically synchronizing the current traffic resource occupancy status managed by WRAS with the resource management unit.

[0067] The Resource Management Unit (RMU) is a functional unit within the existing AS domain control plane. It is responsible for the unified management of network resources within the domain, including addresses, bandwidth, and storage. By dynamically adjusting resource allocation strategies, it provides prioritized data forwarding services at different rates for different types of traffic (e.g., different DSCP values). The RMU establishes sessions with all WRASs within the domain, manages the allocation of all network resources supporting deterministic latency transmission, and can configure synchronization periods to ensure the availability of resources within the domain. Figure 1 This is to prevent duplicate reservations of resources.

[0068] Note 1: In actual deployment, for privacy protection purposes, external AS domains can encapsulate a physical link or subnet as a virtual link. As long as the virtual link is published to the blockchain along with information such as its available resources and latency upper bound, it will not affect the calculation of end-to-end cross-domain routing for deterministic traffic in the source domain, and will reduce the amount of computation.

[0069] Note 2: In actual deployment, if the scheduling rules of adjacent AS domains are different, additional delay will occur in the inter-domain BR due to the difference in the adaptation scheduling rhythm. The upper limit of this delay can be obtained through theoretical analysis and actual measurement statistics, and this upper limit of delay is incorporated into the inter-domain BR delay as a known quantity.

[0070] Note 3: Regarding the upper bound of inter-domain link latency, on the one hand, link latency is proportional to the physical length of the link; on the other hand, environmental changes (such as temperature) can affect the transmission rate of the link. When the physical length of the inter-domain link is long and the change in link latency caused by environmental changes cannot be ignored, a value can be obtained as its upper bound based on historical monitoring data of inter-domain latency and a specific confidence level.

[0071] 2.3 Shaping Parameter Settings

[0072] This function is responsible for configuring shaping parameters for deterministic traffic on the router's ingress interface, i.e., traffic shaping. Based on the deterministic traffic characteristic description (T-Spec) from the user plane, it uses a hybrid token bucket and leaky bucket model to configure the shaping parameters. Specifically, the token bucket rate is set to α% of the minimum bottleneck link bandwidth (e.g., α = 80) to ensure that the traffic does not exceed the link's capacity for deterministic traffic; the leaky bucket capacity is set to the maximum transmission unit (MTU) * maximum burst length * coefficient β (e.g., β = 1) to shape the traffic into smooth, uniform flow.

[0073] Within each AS domain, WRAS uses traffic shaping to control the flow rate of ingress links, ensuring that the traffic entering the network per unit time does not exceed the agreed limit, smoothing burst traffic so that its entry time into the network is relatively balanced, improving the distribution of deterministic traffic in the time dimension, and adapting to the scheduling mechanism.

[0074] 2.4 Traffic Scheduling

[0075] Within each AS domain, WRAS traffic scheduling includes two aspects: ① scheduling among multiple deterministic traffic flows (i.e., traffic orchestration), and ② scheduling between deterministic and non-deterministic traffic flows (i.e., integrated scheduling).

[0076] 1) Scheduling (traffic orchestration) among multiple deterministic traffic flows

[0077] It is responsible for specifying the time unit for transmitting deterministic flows on the router's outgoing interface; based on the time distribution characteristics of the shaped deterministic traffic, as well as the forwarding paths and available resources within the domain obtained from the route calculation, it specifies the sending time of the packets to a specific time unit, so that multiple deterministic flows are forwarded at different times on the shared link segment, thus avoiding conflicts.

[0078] Specifically, a scheduling period is set at the router's outgoing interface, and WRAS orchestrates the time units for transmitting deterministic traffic within this scheduling period. Among these:

[0079] PE routers or BR routers divide deterministic traffic transmission into a series of small time units of length T, and configure a buffer queue for each small time unit to buffer deterministic traffic packets waiting to be sent within this time unit; the buffer capacity of the buffer queue is the product of T and the interface rate, that is, all packets buffered by the queue can be sent within the time unit T.

[0080] WRAS first calculates the number of periodic buffer queues occupied by the deterministic traffic based on its traffic characteristic description (T-Spec). Then, it selects a queue number for the deterministic traffic, specifying the time distribution of its packet transmission, allowing multiple deterministic traffic flows carried on the same link to be transmitted within different small time units. Through this traffic scheduling, it minimizes packet collisions caused by traffic aggregation on shared links, thus avoiding problems such as increased latency, long latency tails, and even packet loss.

[0081] 2) Scheduling between deterministic and nondeterministic traffic

[0082] Bandwidth is reserved in advance for deterministic traffic and prioritized for scheduling when traffic arrives; the difference between the interface bandwidth and the sum of the reserved bandwidth for all deterministic flows of the current WRAS service is used for scheduling non-deterministic traffic.

[0083] 2.5 Performance Measurement

[0084] In addition to the functions and uses mentioned above, the WRAS functional entity can also include a performance measurement unit as needed to actively detect the performance of a link, node, or subnet, such as latency and packet loss. Specifically, this can be achieved through active measurement (such as sending timestamped probe packets), passive measurement (such as collecting flow table statistics), or a combination of measurement (such as flow detection). This allows for the triggering of path reselection in routing calculations when the QoS metrics of a certain path are lower than expected.

[0085] 3. Blockchain

[0086] This invention is based on blockchain for collaborative information sharing and cross-domain traffic transmission, wherein:

[0087] 3.1 Information Sharing

[0088] Each AS domain records the routing, topology, bandwidth, latency, and available resource information of nodes and links supporting deterministic delay forwarding within its domain, as well as the upper bound of latency for BR nodes and the upper bound of latency for inter-domain links between neighboring BRs and its own BR, on the blockchain. To improve data security, this information can be encrypted before uploading; thus, only WRASs with the appropriate permissions can decrypt and access it. WRASs retrieve the necessary information by querying the blockchain when performing route calculations, traffic shaping, and traffic scheduling.

[0089] For example, blockchain-based information sharing can be implemented through the following steps:

[0090] S1. The network controllers and network managers within each AS domain periodically collect the aforementioned routing and topology information within their domain and send this information to the blockchain nodes within that domain. If, to protect the topology details within the domain, several physical links or subnets are encapsulated as virtual links, then information such as the bandwidth, latency, and available resources of these virtual links are sent to the blockchain nodes within that domain.

[0091] S2. The blockchain node encrypts the received information, then packages the encrypted information into a new block according to the blockchain consensus mechanism, and broadcasts it in the blockchain network.

[0092] After receiving a new block, S3 and other blockchain nodes within the AS domain verify the block's legitimacy using a consensus algorithm. If the verification passes, the block is added to its local blockchain ledger.

[0093] S4. When a WRAS within an AS domain needs to make a cross-domain routing decision, it sends a query request to the blockchain nodes within the domain to request routing information to the destination AS domain.

[0094] S5. The blockchain nodes within this domain obtain the routing information to the target AS domain from the blockchain ledger according to the query request, and return it to WRAS, so that WRAS can generate cross-domain routes.

[0095] 3.2, Collaborative Cross-Domain Traffic Transmission

[0096] In wide area networks spanning multiple AS domains, when multiple deterministic traffic flows need to be transmitted, WRAS within each AS domain coordinates based on blockchain. This includes:

[0097] S1, within the source domain, traffic characteristic descriptions (T-Spec) and related requirement information are recorded on the blockchain, including but not limited to source address, destination address, traffic size, transmission start and end time, maximum tolerable latency, bandwidth requirements, and WRAS for the traffic time distribution characteristics after shaping the deterministic traffic, and the AS domains (specifically, the AS domain number sequence) that need to be traversed from the source DES to the destination DES.

[0098] The above information is collected by WRAS and sent to the blockchain nodes within the domain. The blockchain nodes then encrypt and package the information into new blocks, which are then broadcast in the blockchain network.

[0099] S2, other WRASs within the AS domain that pass through the route obtain the above information through the blockchain, and combine it with the load of deterministic traffic already received in their respective domains, (through routing calculation) calculate whether the currently available network resources can provide a domain path with deterministic delay forwarding for the new request traffic and the upper limit of the delay of the path.

[0100] S2.1 If the path exists, it is considered that this domain has the capacity to accept the traffic. Then, each WRAS in the passing domain will send the willingness to accept the traffic to the blockchain node in this domain with an extended upper bound, and reserve resources for the traffic along the transmission path in this domain. The resource reservation result is synchronized with the resource management module of the domain control plane through the second communication interface.

[0101] S2.2 If the path does not exist, WRAS sends the rejection intention to the blockchain nodes within the domain.

[0102] Each blockchain node in the transit domain encrypts the above information, packages it into a new block according to the blockchain's consensus mechanism, and broadcasts it in the blockchain network.

[0103] S3, the source domain's WRAS obtains feedback information from each transit domain via the blockchain. If all transit domains accept the request, deterministic traffic is transmitted along the determined path. Otherwise, if any transit domain does not accept the request, the source domain's WRAS recalculates the route and repeats the above process until a feasible optimal path is determined.

[0104] S4. When deterministic traffic is transmitted along a predetermined path, WRAS performs traffic shaping and scheduling in each AS domain along the route, and sends the actual traffic transmission status information to the blockchain nodes in the domain. The blockchain nodes record this information on the blockchain for other AS domains to query and analyze.

[0105] This invention is not limited to the above-described embodiments. Any obvious improvements, substitutions, or modifications that can be made by those skilled in the art without departing from the essence of this invention are within the scope of protection of this invention.

Claims

1. A method for deterministic time-delay transmission of cross-domain traffic, characterized in that: For deterministic traffic transmitted across domains: Within the source AS domain, route calculations are performed for deterministic traffic, generating a global path from the source DES to the target DES, and traffic characteristic descriptions and demand information are sent to other AS domains. For other routes passing through the AS domain, route calculations are performed for the transmission path of deterministic traffic within this domain, and feedback is given on whether the deterministic traffic can be accepted based on the calculation results; If all AS domains can accept the traffic, then the deterministic traffic is transmitted according to the path determined in the above manner.

2. The method for deterministic time-delay transmission of cross-domain traffic according to claim 1, characterized in that: Information is shared between AS domains via blockchain, including: Each AS domain uploads the routing, topology, bandwidth, latency, and available resource information of nodes and links that support deterministic latency forwarding within its domain, as well as the upper limit of latency for BR nodes and the upper limit of latency for inter-domain links between neighboring BRs and its own BRs, to the blockchain network. Within the source AS domain, global path routing calculations are performed based on shared information, and traffic characteristic descriptions and demand information are uploaded to the blockchain network; If there exists an intra-domain path with deterministic delay forwarding within each AS domain, the acceptable intention and the corresponding intra-domain path's delay upper bound will be uploaded to the blockchain network.

3. The method for deterministic delay transmission of cross-domain traffic according to claim 1, characterized in that: The routing calculation is as follows: the objective is to minimize the upper bound of latency, and the constraint is that the available resources for each process are greater than or equal to the resources required by the deterministic traffic. Within each AS domain, after route calculation, resource reservation is initiated according to the deterministic traffic transmission path within the domain.

4. The method for deterministic delay transmission of cross-domain traffic according to claim 1, characterized in that: Each AS domain performs traffic shaping and traffic scheduling for deterministic traffic transmitted within the domain.

5. The cross-domain traffic deterministic delay transmission method according to claim 4, characterized in that: The traffic scheduling includes: Traffic orchestration among multiple deterministic traffic streams: Based on the traffic characteristics description of the deterministic traffic streams, calculate the number of buffer queues occupied by the stream, select the buffer queue sequence number for the deterministic traffic streams, and distribute the multiple deterministic traffic streams carried on the same link for transmission in different time units; Integrated scheduling among multiple deterministic traffic flows: bandwidth is reserved for deterministic traffic. The difference between the interface bandwidth and the total reserved bandwidth for all deterministic flows currently being served is used for scheduling nondeterministic traffic.

6. The cross-domain traffic deterministic delay transmission method according to claim 4, characterized in that: The traffic shaping is as follows: based on the deterministic traffic characteristic description, a hybrid model of token bucket and leaky bucket is used to configure shaping parameters; wherein, the token bucket rate is set at α% of the minimum bottleneck link bandwidth, and the leaky bucket capacity is set at the maximum transmission unit (MTU) * maximum burst length * coefficient β.

7. A cross-domain traffic deterministic delay transmission system, characterized in that: Each AS domain has a WRAS deployed, which is responsible for performing route calculations for deterministic traffic and for traffic shaping and scheduling during traffic transmission. The blockchain network is jointly maintained by blockchain nodes set up in each AS domain and is used to share information for WRAS in each AS domain. Based on the cross-domain traffic deterministic delay transmission method according to any one of claims 1 to 6, deterministic traffic is transmitted.

8. The cross-domain traffic deterministic delay transmission system according to claim 7, characterized in that: The WRAS is deployed on the ingress router where deterministic traffic enters the AS domain, including: Deploy WRAS at the PE router connected to DES to perform global route calculations for deterministic traffic from DES within the domain to DES outside the domain, and to shape and schedule deterministic traffic within the domain. Deploy WRAS at the BR router at the entry point of each AS domain to respond to the source domain, formulate the actual transmission path of deterministic traffic within the domain, and shape and schedule deterministic traffic from adjacent AS domains.

9. The cross-domain traffic deterministic delay transmission system according to claim 7, characterized in that: Within each AS domain, WRAS has a secure communication channel with the blockchain nodes.

10. The cross-domain traffic deterministic delay transmission system according to claim 7, characterized in that: The WRAS is also responsible for actively performing performance testing on links, nodes, or subnets, including latency and packet loss; the testing methods are active measurement, passive measurement, or a combination of both.

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