Label switching-oriented credit value flow control method

Abstract

The invention provides a label switching-oriented credit value flow control method, which comprises the following steps of: performing two-tuple marking of forwarding equivalence classes and tunnel IDs at an ingress router, and binding a corresponding credit value for each forwarding equivalence class; when it is detected that the forwarding equivalence class carries out traffic transmission, controlling the credit value corresponding to the forwarding equivalence class to be reduced from an initial value to zero at a preset sending slope so as to prevent traffic transmission, and then controlling the credit value to be increased from zero to the initial value at a preset idle slope so as to recover traffic transmission; wherein the sending slope is the slope of the credit value falling process along with the time, and the idle slope is the slope of the credit value rising process along with the time. Therefore, the invention can effectively prevent a single service from occupying excessive bandwidth, and optimize fair distribution of network resources.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a credit value flow control method oriented to label switching. Background Art

[0002] With the continuous development of communication network technology, the complexity and diversity of network traffic are increasing, and the existing network traffic control mechanism is facing more and more challenges. Multi-protocol Label Switching (MPLS) technology is widely used in the network to efficiently manage network traffic through label forwarding mechanism. However, the current label switching mechanism lacks a simple and efficient traffic control strategy, especially when facing multiple types of services, which may cause a certain type of traffic with the same priority to occupy a large amount of network resources, while other services lack transmission opportunities. This unbalanced resource allocation can easily cause network congestion and reduce overall network performance.

[0003] Existing traffic control and scheduling strategies are not flexible enough or have deficiencies.

[0004] The token bucket mechanism mainly relies on fixed-rate token generation to control traffic rate. This fixed rate cannot dynamically adapt to changes in network load and it is difficult to ensure the real-time control of service transmission rate. This mechanism also has weak support for service hierarchical transmission and it is difficult to comprehensively consider the transmission rate requirements of services of different priorities and cannot meet the needs of high-priority traffic.

[0005] The priority scheduling mechanism sets static priorities for different service flows to ensure the transmission of high-priority flows; however, this mechanism easily results in low-priority flows not being able to obtain transmission opportunities when the network load is heavy, and lacks support for the transmission of bursty service flows. At the same time, the static division of priority scheduling also lacks flexibility and cannot dynamically adjust the transmission rate of flows according to the actual network load. Summary of the invention

[0006] The purpose of the present invention is to provide a credit value flow control method for label switching, which is used to improve the bandwidth utilization of the network, enhance the scheduling capability of the network when facing complex business requirements, and meet the efficient transmission requirements in the modern network environment.

[0007] In order to achieve the above object, the present invention provides a credit value flow control method for label switching, characterized in that it includes the steps of:

[0008] Performing a binary tag of a forwarding equivalence class and a tunnel ID at an ingress router, and binding a corresponding credit value to each forwarding equivalence class;

[0009] When it is detected that the forwarding equivalence class is transmitting traffic, the credit value corresponding to the forwarding equivalence class is controlled to decrease from an initial value to zero at a preset sending slope to prevent the traffic transmission, and then the credit value is controlled to increase from zero to the initial value at a preset idle slope to resume the traffic transmission; wherein the sending slope is the slope of the credit value decreasing process changing with time, and the idle slope is the slope of the credit value increasing process changing with time, and the sending slope and / or idle slope of the service can be dynamically adjusted according to the service demand during the transmission process.

[0010] Optionally, the sending slope and the idle slope have the following proportional relationship:

[0011] S dowm =kS up ;

[0012] Among them, S dowm is the sending slope, S up is the idle slope, and k is an adjustable proportional coefficient.

[0013] Optionally, the flow rate is calculated based on a single transmission cycle in which the credit value changes based on the following formula:

[0014]

[0015] Among them, T down is the sending time of the traffic in a single transmission cycle, T up C is the idle time of traffic in a single transmission cycle; i is the credit value;

[0016] The total time for traffic transmission is calculated based on the following formula:

[0017]

[0018] The actual bandwidth of the traffic is calculated based on the following formula:

[0019]

[0020] Among them, B is the bandwidth of the transmission port, D total The total amount of data that needs to be transferred.

[0021] Optionally, also include:

[0022] The sending slope and the idle slope are optimized and solved through a weighted multi-objective optimization model.

[0023] Optionally, the expression of the multi-objective optimization model is:

[0024]

[0025] C i (t)≥0;

[0026] The actual bandwidth constraint of the traffic is:

[0027]

[0028] The minimum bandwidth guarantee constraint for the traffic is:

[0029] B i (t)≥B min,i ,

[0030] The traffic priority and slope adjustment constraints of the traffic are:

[0031] s down,i ∈[s down,min,i ,s down,max,i ],

[0032] Among them, λ1, λ2, and λ3 are adjustable preset weights, B i (t) is the actual rate of flow i, B min,i The minimum bandwidth set for flow i, s down,i is the sending slope corresponding to flow i, s duwn,min,i is the preset minimum sending slope, s down,max,i The preset maximum sending slope can adjust the sending slope and idle slope ratio coefficient of different priority services according to the optimization target to adapt to new transmission requirements.

[0033] The present invention introduces a credit value mechanism to allocate a corresponding credit value to each flow in the network, and performs credit value evaluation and dynamic scheduling; when a certain flow is continuously transmitted, its credit value gradually decreases until it reaches a critical value and suspends transmission, providing transmission opportunities for other flows; when the flow is in an idle state, that is, when transmission is suspended, its credit value gradually recovers until it recovers to the initial value before resuming the transmission of the flow, and the proportional coefficient of the sending slope and the idle slope can be adjusted according to the optimization function to achieve dynamic control of the transmission rate of different services; in this way, the credit value-based mechanism of the present invention can ensure that flows of different business types compete for transmission opportunities fairly, effectively avoid traffic congestion and resource waste, and thus improve the overall performance of the network. At the same time, the present invention also provides a comprehensive mathematical model, which ensures the effectiveness and fairness of flow control through scientific calculation and real-time adjustment; it not only provides the bandwidth utilization of the network, but also can enhance the scheduling ability of the network in the face of complex business needs, and meet the efficient transmission needs in the modern network environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A flowchart of the steps of the credit value flow control method for label switching provided by an embodiment of the present invention;

[0035] Figure 2 A schematic diagram of an application of the credit value flow control method for label switching provided by an embodiment of the present invention in a label forwarding mechanism;

[0036] Figure 3 A line graph showing changes in multiple credit values ​​in actual application of the credit value flow control method for label switching provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0038] It should be noted that references to "one embodiment", "embodiment", "example embodiment", etc. in this specification refer to the embodiment described, which may include specific features, structures or characteristics, but not every embodiment must include these specific features, structures or characteristics. In addition, such expressions do not refer to the same embodiment. Furthermore, when describing specific features, structures or characteristics in conjunction with an embodiment, whether or not there is an explicit description, it has been shown that it is within the knowledge of those skilled in the art to combine such features, structures or characteristics into other embodiments.

[0039] In addition, certain words are used in the specification and subsequent claims to refer to specific components or parts. Those with ordinary knowledge in the relevant field should understand that manufacturers can use different nouns or terms to refer to the same component or part. This specification and subsequent claims do not use differences in names as a way to distinguish components or parts, but use differences in the functions of components or parts as the criteria for distinction. "Including" and "including" mentioned throughout the specification and subsequent claims are open-ended terms and should be interpreted as "including but not limited to". In addition, the word "connected" here includes any direct and indirect electrical connection means. Indirect electrical connection means include connection through other devices.

[0040] With regard to the existing network based on label switching, there is competition between services with the same priority in the same forwarding channel, and high-priority services will excessively preempt the transmission resources of low-priority services. At the same time, the existing service flow control strategy is not flexible enough, and it is difficult to flexibly adjust the transmission rate of different flows while forwarding according to the current network load status. The present invention provides a credit value flow control method for label switching. By introducing a credit value mechanism, credit value evaluation and dynamic scheduling are performed on each flow in the network, which effectively avoids flow congestion and resource waste, and improves the overall performance of the network.

[0041] The method is mainly applied to the label forwarding mechanism, the core of which is to exchange fixed-length labels between various nodes in the network (including ingress nodes, relay nodes and egress nodes). These labels are searched and updated in the label switching router (Label Information Base, LIB) of the network device; each label is associated with a specific forwarding path LSP i Associated.

[0042] See also Figure 2 ,The label forwarding path consists of the following parts:

[0043] Ingress: Responsible for receiving traffic and assigning a label to it based on the FEC (Forwarding Equivalence Class) of the traffic.

[0044] Transit (relay node): Determines the next hop for traffic based on label exchange and updated traffic labels.

[0045] Egress (exit node): receives labels from relay nodes and finally sends traffic to the destination.

[0046] In the same channel, for each forwarding equivalence class i in the channel, it can be independently described by the following mathematical expression:

[0047] LSP i ={FEC i ,TID i};

[0048] Among them, FEC i Indicates the forwarding equivalence class of the traffic, TID i It is the label tunnel ID corresponding to the traffic, which is used to determine the specific transmission path of the traffic, LSP i It can represent a forwarding equivalence class in the tunnel.

[0049] Figure 1 A credit value flow control method for label switching provided by an embodiment of the present invention is shown, and the method includes:

[0050] S101: marking the binary of the forwarding equivalence class and the tunnel ID at the ingress router, and binding a corresponding credit value to each forwarding equivalence class; Figure 2 As shown, there are three forwarding equivalence classes, namely FEC1, FEC2, and FEC3. At the ingress router, the corresponding forwarding equivalence class and the tunnel ID are marked as a binary, and then a corresponding credit value is bound to each forwarding equivalence class. The credit values ​​bound to different forwarding equivalence classes can be the same or different. Specifically, the credit value corresponding to FEC1 is C1, the credit value corresponding to FEC2 is C2, and the credit value corresponding to FEC3 is C3. The three credit values ​​can be set as initial values ​​based on the importance or priority of the forwarding equivalence class. In this embodiment, the label credit value in the tunnel will be changed at the ingress node, and the transmission of traffic will be regulated based on the change of the credit value.

[0051] S102: When the forwarding equivalence class is detected to be transmitting traffic, the credit value corresponding to the forwarding equivalence class is controlled to decrease from the initial value to zero at a preset sending slope to prevent traffic transmission, and then the credit value is controlled to increase from zero to the initial value at a preset idle slope to resume traffic transmission; wherein, the sending slope is the slope of the credit value decreasing process changing over time, and the idle slope is the slope of the credit value increasing process changing over time. That is, the credit value will change dynamically with the transmission of traffic, and the traffic transmission will be regulated at the label network ingress node Ingress. The credit value specifically includes two changing states, as follows:

[0052] 1. Credit value decreases: When traffic is transmitted, the credit value decreases along with the transmitted business volume at a rate of a preset sending slope, which indicates that the traffic is occupying bandwidth resources. When the credit value drops to a critical value (specifically 0 in this embodiment), traffic transmission is blocked, that is, the traffic loses the transmission opportunity at this time.

[0053] 2. Credit value rise: When the traffic is blocked or idle, its credit value gradually recovers with the transmission volume at a preset idle slope rate (no transmission in this recovery phase). When the credit value returns to the initial value C i When the traffic is transmitted, it can regain the transmission opportunity, that is, resume traffic transmission. The sending slope and / or idle slope of this embodiment can be dynamically adjusted according to the business demand during the transmission process to meet the actual demand.

[0054] See also Figure 3The figure shows the forwarding status of three credit values ​​C1, C2, and C3 under different slope states. The colored part is the time when the service can be forwarded, and the gray part is the time when the service cannot be forwarded. Therefore, the purpose of controlling traffic can be achieved by adjusting the slope corresponding to different traffic.

[0055] This embodiment defines each flow based on the label forwarding class and assigns a credit value to it. As the flow is transmitted, the credit value gradually decreases. When it reaches the critical value, the flow is suspended to provide transmission opportunities for other flows. When the flow is idle, the credit value is gradually restored and the transmission priority is regained. Through this mechanism, it is possible to effectively avoid a single service from occupying too much bandwidth and optimize the fair allocation of network resources.

[0056] This embodiment dynamically affects the credit value and transmission opportunity of the traffic by defining the sending slope and the idle slope; compared with the traditional token bucket algorithm and priority scheduling, the slope mechanism can adjust the transmission opportunity of each traffic in real time during the transmission process, rather than relying solely on statically allocated bandwidth or fixed priority.

[0057] In an optional implementation manner, the sending slope and the idle slope have the following proportional relationship:

[0058] S dowm =kS up ;

[0059] Among them, S dowm is the sending slope, S up is the idle slope, and k is an adjustable proportional coefficient. In a specific implementation, the system can flexibly control the transmission frequency and priority of the traffic by adjusting the parameter k corresponding to each type of traffic.

[0060] Exemplarily, the proportional coefficient k of the sending slope and the idle slope may be adjusted according to the optimization function to achieve dynamic control of the transmission rates of different services.

[0061] In each transmission cycle, the traffic will experience a change from the credit value C i Decrease to 0 and then return to C i This process is divided into two stages. The sending time T in a single transmission cycle is calculated by the following formula: down and free time T up :

[0062]

[0063]

[0064] Among them, T down is the sending time of the traffic in a single transmission cycle, Tup C is the idle time of traffic in a single transmission cycle; i is the credit value.

[0065] Furthermore, the flow rate is calculated based on the following formula for a single transmission cycle of the credit value variation:

[0066]

[0067] During the entire network operation, the system will dynamically adjust the transmission status of each flow according to the credit value. Each time, the flow will experience several credit values ​​from 0 to C. i The time period is only i There is a transmission opportunity in the process of decreasing to 0. Assume that the bandwidth of the transmission port is B and the total amount of data to be transmitted is D. total , the total time of traffic transmission T total It can be obtained by summing the time of each transmission cycle:

[0068]

[0069] Due to the dynamic adjustment of the credit value, the actual bandwidth of the traffic is affected by the sending slope and the idle slope. The actual bandwidth B actual It can be calculated based on the total time of the entire transmission cycle:

[0070] After simplification, the actual bandwidth of a single flow is B actual Calculated based on the following formula:

[0071]

[0072] Thus, the calculation method provided by this embodiment has greater flexibility and accuracy than the existing token bucket algorithm and the traditional priority scheduling mechanism. The traditional algorithm is often unable to adapt to the real-time fluctuation of the network load, while the present invention can respond to the change of the network state in time and optimize the utilization of bandwidth resources by dynamically adjusting the sending slope and the idle slope.

[0073] Optionally, this embodiment further includes: optimizing and solving the sending slope and the idle slope through a weighted multi-objective optimization model. In specific implementation, the expression of the multi-objective optimization model is:

[0074]

[0075] C i (t)≥0;

[0076] The actual bandwidth constraint of the traffic in this model is:

[0077] That is, the sum of the actual rates of all traffic should not exceed the bandwidth of the channel.

[0078] In order to ensure that certain key traffic (such as real-time audio and video or emergency data) can obtain a minimum bandwidth allocation, a minimum bandwidth guarantee constraint can be set; preferably, the minimum bandwidth guarantee constraint of the traffic is:

[0079] B i (t)≥B min,i , It can be applied to services that require bandwidth guarantee.

[0080] The slope mechanism of this embodiment can be combined with priority scheduling to ensure that traffic of different priorities can obtain transmission opportunities that match their priorities. The traffic priority and slope adjustment constraints of the configurable traffic are:

[0081] s down,i ∈[s down,min,i ,s down,max,i ],

[0082] Among them, λ1, λ2, and λ3 are adjustable preset weights, B i (t) is the actual rate of flow i, B min,i The minimum bandwidth set for flow i, s down,i is the sending slope corresponding to flow i, s down,min,i is the preset minimum sending slope, s down,max,i It is the preset highest sending slope.

[0083] Specifically, multiple optimization objectives can be designed according to the current model, and the k of each flow can be dynamically adjusted. i Parameters, under the premise of satisfying various constraints, the maximum optimization target, for the setting of the optimization target, the maximum total bandwidth (maximum bandwidth utilization), maximum minimum bandwidth (fairness), minimization of bandwidth allocation variance (load balancing), etc. can be used as the optimization target, and the proportion of different optimization targets can be achieved by adjusting the weights λ of different optimization targets.

[0084] This embodiment can adjust the proportional coefficient between the sending slope and the idle slope of each type of service according to the service transmission situation to adjust the service transmission rate (bandwidth); and achieve transmission optimization of multiple forwarding equivalence classes according to the optimization target.

[0085] In practical applications, the credit value mechanism and slope adjustment strategy provided in this embodiment have good application effects in MPLS or SR networks, and can realize efficient allocation of network resources and dynamic control of traffic scheduling. Compared with the traditional token bucket and priority scheduling mechanism, the present invention has higher flexibility and fairness, and is suitable for various dynamic network environments; at the same time, it can be combined with QoS technology for differentiated flow scheduling. In summary, the present invention introduces a credit value mechanism to allocate corresponding credit values ​​to each flow in the network, and performs credit value evaluation and dynamic scheduling; when a certain flow is continuously transmitted, its credit value gradually decreases until it reaches a critical value and suspends transmission, providing transmission opportunities for other flows; when the flow is in an idle state, that is, when the transmission is suspended, its credit value gradually recovers until it recovers to the initial value before resuming the transmission of the flow; in this way, the credit value-based mechanism of the present invention can ensure that flows of different business types compete fairly for transmission opportunities, effectively avoiding traffic congestion and resource waste, and thus improving the overall performance of the network. At the same time, the present invention also provides a comprehensive mathematical model to ensure the effectiveness and fairness of traffic control through scientific calculations and real-time adjustments; it not only improves the bandwidth utilization of the network, but also enhances the scheduling capability of the network in the face of complex business needs, and meets the needs of efficient transmission in modern network environments.

[0086] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A credit value flow control method for label switching, characterized in that: Includes steps: Performing a binary tag of a forwarding equivalence class and a tunnel ID at an ingress router, and binding a corresponding credit value to each forwarding equivalence class; When it is detected that the forwarding equivalence class is transmitting traffic, the credit value corresponding to the forwarding equivalence class is controlled to decrease from an initial value to zero at a preset sending slope to prevent the traffic transmission, and then the credit value is controlled to increase from zero to the initial value at a preset idle slope to resume the traffic transmission; wherein the sending slope is the slope of the credit value decreasing process changing with time, and the idle slope is the slope of the credit value increasing process changing with time.

2. The credit value flow control method for label switching according to claim 1, characterized in that: The sending slope and the idle slope have the following proportional relationship: S dowm =kS up ; Among them, S dowm is the sending slope, S up is the idle slope, and k is an adjustable proportional coefficient.

3. The credit value flow control method for label switching according to claim 2, characterized in that: The flow rate is calculated based on the credit value change for a single transmission cycle based on the following formula: Among them, T down is the sending time of the traffic in a single transmission cycle, T up C is the idle time of traffic in a single transmission cycle; i is the credit value; The total time for traffic transmission is calculated based on the following formula: The actual bandwidth of the traffic is calculated based on the following formula: Among them, B is the bandwidth of the transmission port, D total The total amount of data that needs to be transferred.

4. The credit value flow control method for label switching according to claim 3, characterized in that: Also includes: The sending slope and the idle slope are optimized and solved through a weighted multi-objective optimization model.

5. The credit value flow control method for label switching according to claim 4, characterized in that: The expression of the multi-objective optimization model is: C i (t)≥0; The actual bandwidth constraint of the traffic is: The minimum bandwidth guarantee constraint for the traffic is: The traffic priority and slope adjustment constraints of the traffic are: Among them, λ1, λ2, and λ3 are adjustable preset weights, B i (t) is the actual rate of flow i, B min,i The minimum bandwidth set for flow i, s down,i is the sending slope corresponding to flow i, s duwn,min,i is the preset minimum sending slope, s down,max,i It is the preset highest sending slope.

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