QoS management system and method of SDN controller

[0037] The present invention will be further described now in conjunction with accompanying drawing.

[0038] refer to figure 1 , the SDN controller QoS management system of the present invention is located in the controller of the SDN control plane, the system includes a core module and an auxiliary module, the core module includes a network state database module, an application information extraction module and a QoS routing calculation module; The auxiliary modules include a network topology management module, a link state discovery module and a flow table automatic distribution module.

[0039] The network topology management module is used to generate and manage network topology information, and the obtained results are transmitted to the network state database module.

[0040] The link state discovery module is used to obtain the link state of the data plane, and the obtained result is transmitted to the network state database module.

[0041] The network state database module is used to store the network topology information and link state information acquired from the topology management module and the link state discovery module.

[0042] The application information extraction module extracts data packet information, and sends the data packet information to the QoS routing calculation module. Wherein, the data packet information includes data packet source IP address, destination IP address and application feature information. The application feature information refers to the field information that can reflect the service level required by the application data packet, such as the service type field of the IPv4 protocol, or the service flow category field of the IPv6 protocol, or the field of other predefined protocols reflecting the application type, etc., the above As the application feature information, the field that can reflect the QoS information of the data flow service needs to be filled with valid information before the data flow is sent or enters the SDN controller control domain.

[0043] The QoS routing calculation module calculates the data flow transmission path according to the network state information extracted from the network state database module and the data packet information input by the application information extraction module, and the obtained result is transmitted to the The flow table is automatically delivered to the module. Specifically, the QoS routing calculation module will query the application feature information and QoS level mapping table according to the application feature information extracted from the application information extraction module. If a matching QoS level value can be obtained, this value will be used as The QoS level of the application; if the corresponding QoS level value does not match, the default QoS value will be used as the QoS level of the application. The QoS routing calculation module also calculates the data flow transmission path through a constrained shortest path first (CSPF) algorithm according to the applied QoS level, in combination with the network state information extracted from the network state database module, and obtains The result is transmitted to the automatic delivery module of the flow table. In this embodiment, the QoS routing calculation module uses the constrained shortest path first (CSPF) algorithm to calculate the path, and in other embodiments, other algorithms, such as heuristic algorithms, can also be used to calculate the path.

[0044] The automatic distribution module of the flow table calculates and generates the corresponding flow table according to the data flow path information obtained by the QoS routing calculation module, calls the controller flow table delivery API provided by the SDN controller, and the controller flows The table delivery API completes the flow table delivery.

[0045] The above is a description of the SDN controller QoS management system of the present invention, below on the basis of the system figure 2 The corresponding QoS path selection method is described.

[0046] Step 1), after the SDN data plane switch receives the application data packet that does not match the flow table, the data packet is uploaded to the control plane SDN controller through the OpenFlow protocol channel;

[0047] Step 2), the application information extraction module receives the above data packet that does not match the flow table, parses the data packet header, obtains information such as the source IP address of the data packet, the destination IP address and the application characteristic information, and sends the above information to the QoS routing calculation module .

[0048] The application feature information involved in this step refers to the field information that can reflect the service level required by the application data packet, such as the service type field of the IPv4 protocol, or the service flow category field of the IPv6 protocol, or the field of other predefined protocols reflecting the application type Wait.

[0049] Step 3), the QoS routing calculation module requests current network status information from the network status database module, including current network topology structure and link status information;

[0050] Step 4), according to the application feature information obtained in step 2), search the application feature information and QoS level mapping table maintained by the QoS routing calculation module, and determine the QoS level of the corresponding application of this data packet; wherein,

[0051] The feature information and QoS level mapping table records the correspondence between preset application feature information and QoS levels. The QoS level indicates the QoS required by the application data flow and the QoS that can be satisfied by the actual path link of the physical network, including: path delay, delay jitter, available bandwidth information, and a combination of one or more of the above. For example, when the network packet is of IPv4 type and the ToS field value is 001 (Priority, priority), the corresponding QoS level is 2; and when the QoS level is 2, the corresponding network status is "the overall delay is less than 40ms ". The setting of the above QoS level and its corresponding relationship with application characteristic information and network status are not limited to the above description, and are definable.

[0052] Step 5), according to the network status information obtained in step 3), and the QoS level requirements determined in step 4), calculate the feasible shortest path between the source IP address and the destination IP address of the data packet.

[0053] Step 6), if there are multiple shortest paths obtained according to step 5), then select the path with the least number of hops, and the path selection ends; otherwise, if the link cannot generate a feasible path between the packet source and the destination IP address after pruning , the path selection fails and the packet will be discarded.

[0054] In the above-mentioned technical solution, described step 5) further includes:

[0055] Step 5-1), the QoS routing calculation module will request network status information from the network status database module, including the current network topology and link operation status.

[0056] Step 5-2), the QoS routing calculation module cuts out all the links that do not meet the QoS requirements based on the available topology of the above network and according to the network status restrictions determined by the applied QoS level. For example, if the application QoS class requires a path bandwidth of at least 5M, then all links in the above topology whose bandwidth does not meet this requirement will be pruned to meet the application QoS constraints.

[0057] Described step 6) also comprises:

[0058] If a feasible path meeting the QoS level requirements is obtained, the path information is delivered to the flow table automatic delivery module; otherwise, the route calculation process is ended, and the data packet will be discarded.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than limit them. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent replacements to the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention, and all of them should be included in the scope of the present invention. within the scope of the claims.