TWI558133B - Controlling method, controller and packet processing method for a software-defined network - Google Patents

Description

Software definition network control method, controller and packet processing method

The disclosure relates to a bandwidth aggregation technology of an SDN (Software-Defined Network), and particularly relates to a software definition network control method, a controller, and a packet processing method.

Smart phones with multiple network interfaces are already very common. This smart phone can connect to multiple wireless networks at the same time and establish multiple network connections. These wireless networks connect to the Internet for the access and use of the Internet's services and resources.

The current bandwidth aggregation technology is to set up a centralized network device on the network side, called an aggregation point (AE: aggregation entity). Aggregation points aggregate multiple network connections of a smartphone into a single network connection. If one of the wireless networks is not available due to factors such as signal interference or mobile phone movement, the aggregation point allows the smartphone's packets to be freely switched between the rest of the wireless network, so that the transmission is not interrupted.

The current aggregation point is centralized, that is, there may be a large number of smart phones sharing an aggregation point to connect to the Internet.

The present disclosure provides a software-defined network control method, controller, and packet processing method, which uses a software-defined network of multiple switches to replace a traditional single aggregation point to avoid bottleneck effects of centralized aggregation points.

The control method of the present disclosure can be used for a software-defined network, comprising the steps of: receiving a registration message from a user equipment, wherein the registration message includes a network access status of the user equipment; and selecting a software-defined network exchange according to the network access status. One of the devices is an aggregation point of the user equipment; calculating a plurality of routing paths between the user equipment and the aggregation point, wherein each of the foregoing routing paths is coupled to one of a plurality of network interfaces of the user equipment; The aggregation point and each of the plurality of routing paths set a routing rule to bypass the packet between the user equipment and the remote network.

The packet processing method of the present disclosure may be used in a software-defined network, including the steps of: receiving an uplink packet transmitted by a user equipment to a remote network; removing a channel header of the uplink packet, and transmitting the uplink packet to the remote network; Receiving a downlink packet transmitted by the remote network to the user equipment; selecting one of a plurality of routing paths coupled to the user equipment to transmit the downlink packet; and adding a channel header corresponding to the selected routing path to the downlink packet And then transmitting the downlink packet to the user equipment through the selected routing path.

The controller of the present disclosure can be used in a software-defined network, including a network interface and processor. The network interface is coupled to the software-defined network to transmit and receive packets for the controller. The processor is coupled to the network interface and performs the above-described control method of the software-defined network.

The above-mentioned software-defined network control method, controller, and packet processing method can specify different aggregation points for each user equipment, which can effectively distribute the load of the traditional single aggregation point, and it is difficult to form a transmission performance bottleneck around the dispersed aggregation points. To avoid network congestion.

The above described features and advantages of the present invention will be more apparent from the following description.

100‧‧‧Software Definition Network

110‧‧‧ Controller

121~124‧‧‧Switch

131~134‧‧‧Edge device

140‧‧‧User equipment

150‧‧‧Remote network

210~260, 310~340, 410~450, 610~640, 810~850‧‧‧ process steps

910, 930‧‧‧ network interface

920, 940‧‧‧ processor

1 is a schematic diagram of a software-defined network in accordance with an embodiment of the present disclosure.

2 to FIG. 4 are flowcharts of a method for controlling a software-defined network according to an embodiment of the disclosure.

FIG. 5 is a schematic diagram of a software defined network in accordance with another embodiment of the present disclosure.

FIG. 6 is a flowchart of a method for controlling a software-defined network according to an embodiment of the disclosure.

FIG. 7 is a schematic diagram of a software defined network in accordance with another embodiment of the present disclosure.

FIG. 8 is a control side of a software-defined network according to an embodiment of the disclosure. Flow chart of the law.

9 is a schematic diagram of a controller and an exchanger in accordance with an embodiment of the present disclosure.

FIG. 1 is a schematic diagram of a software defined network 100 in accordance with an embodiment of the present disclosure. The software definition network 100 includes a controller 110 and switches 121-124. The controller 110 and the switches 121-124 are coupled to each other within the software-defined network 100. The controller 110 controls the network topology and packet routing of the entire software-defined network 100. The switch 124 is coupled to the remote network 150. The remote network 150 can be the Internet or the internal network of a company or organization. The base station 131 is coupled to the switch 121. An access point (AP) is coupled to the switch 122. The access point 133 and the base station 134 are coupled to the switch 123.

Base stations 131, 134 and access points 132, 133 may be referred to as edge devices, respectively belonging to different wireless networks. The user device 140 can be a network-enabled mobile electronic device such as a smart phone or a tablet. The user equipment 140 has a plurality of network interfaces, each of which can be connected to an edge device to connect to the remote network 150 through the wireless network to which the edge device belongs and the software-defined network 100. In this embodiment, the base stations 131 and 134 are base stations of a Long Term Evolution (LTE) network. Access points 132 and 133 are access points for a wireless fidelity (Wi-Fi) network. One network interface of the user equipment 140 is connected to the LTE base station 131, and the other network interface is connected to the Wi-Fi access point 132.

The disclosure is not limited to two wireless networks, LTE and Wi-Fi. Another embodiment of the present disclosure may include other types of wireless networks, such as a 3G network and a Worldwide Interoperability for Microwave Access (WiMAX) network, for the user equipment 140 to connect to the software-defined network 100 and Remote network 150.

FIG. 2 is a flowchart of a method for controlling a software definition network 100 according to an embodiment of the disclosure. FIG. 2 illustrates a flow of registration to the controller 110 when the user equipment 140 connects to the software-defined network 100 in the above control method. In step 210, the user equipment 140 sends a registration message through a network interface. This registration message includes the network access status of the user device 140. The network access status described above records the edge device to which each network interface of the user equipment 140 is connected and the wireless network to which the edge device belongs. At step 220, the switch 121 or 122 receives the registration message and forwards the registration message to the controller 110. At step 230, the controller 110 receives a registration message from the user device 140. The controller 110 may select one of the switches 121-124 as the aggregation of the user equipment 140 according to the network access status of the user equipment 140 and the load of each of the switches 121-124 of the software definition network 100 in step 230. point. In this embodiment, the aggregation point selected by the controller 110 is the switch 121.

The controller 110 may also calculate a plurality of routing paths between the user equipment 140 and the aggregation point 121 in step 230, wherein each of the routing paths couples the aggregation point 121 and the plurality of network interfaces of the user equipment 140. one of them. There are two routing paths in this embodiment. The first routing path includes a base station 131 corresponding to the LTE network to which the base station 131 belongs. The second routing path includes access point 132 and switching The device 122 corresponds to the Wi-Fi network to which the access point 132 belongs.

Controller 110 may also assign the network address of user equipment 140 and the network address of aggregation point 121 in step 230. User equipment 140 requires a network address to receive downstream packets from remote network 150. Aggregation point 121 requires a network address to aggregate upstream packets sent by user equipment 140.

Next, at step 240, the controller 110 sets a flow entry at the aggregation point 121 and each of the plurality of routing paths to bypass the user device 140 and the remote network 150. Packet. Aggregation point 121 may remove the tunnel header for the upstream packet according to these routing rules and add a channel header to the downstream packet. The remaining switches may forward the packets of the user equipment 140 to the user equipment 140, the aggregation point 121, or the remote network 150 in accordance with these routing rules.

At step 250, the controller 110 transmits the network address of the user equipment 140 and the network address of the aggregation point 121 to the user equipment 140. At step 260, user equipment 140 performs its own network address setting and records the network address of aggregation point 121. The registration process is now complete. The network address of the aggregation point 121 can be a common aggregation point network address, that is, the network addresses of all the aggregation points in the software definition network 100 can be the same. Because the different user equipments 140 have different network addresses, the controller 110 can route the packets of the user equipment 140 to the aggregation point 121 to which the user equipment 140 belongs according to the network address of the user equipment 140.

FIG. 3 is a flowchart of a method for controlling a software definition network 100 according to an embodiment of the disclosure. FIG. 3 illustrates the user equipment 140 in the above control method. The process of sending an upstream packet. The so-called uplink packet refers to a packet that the user equipment 140 transmits to the remote network 150. At step 310, user equipment 140 may analyze the packet to determine the proportion of transmission of the upstream packet between the plurality of network interfaces. In step 320, the user equipment 140 selects the Wi-Fi network to which the LTE network or access point 132 to which the base station 131 belongs according to the transmission ratio to transmit the uplink packet. The user equipment 140 adds the uplink packet to the channel header corresponding to the selected wireless network, and the destination address in the channel header is the network address of the aggregation point 121. The user equipment 140 then transmits the upstream packet to the aggregation point 121 via the selected wireless network.

At step 330, aggregation point 121 receives the upstream packet and removes the channel header of the upstream packet. Then at step 340, aggregation point 121 transmits the upstream packet to remote network 150 in accordance with the routing rules.

The user equipment 140 is connected to multiple wireless networks at the same time, and the packets of the same service flow may be transmitted in multiple wireless networks, and the packets are aggregated at the aggregation point 121. Because the upload speed of each wireless network may be different, the order in which these packets arrive at the aggregation point 121 may be different from the order in which the user equipment 140 is sent. In order to correct the problem of the disorder of the sequence, for each service flow between the user equipment 140 and the remote network 150, the aggregation point 121 can receive the uplink packet of the service flow and remove the channel header of the uplink packet. These uplink packets are sorted according to the sequence number of these uplink packets, and then these uplink packets are sequentially transmitted to the remote network 150. The sequence number of the uplink packet may be located in the channel header of the uplink packet.

The aggregation point 121 can set a sorting queue for each service flow between the user equipment 140 and the remote network 150, and use the sorting queue to sort the uplink packets of the corresponding service flow. When the aggregation point 121 receives an uplink packet, the uplink packet may be placed in the sequence queue corresponding to the service flow to which the uplink packet belongs. The location of the upstream packet in the queue is determined by the sequence number of the upstream packet. Packets with a smaller sequence number are arranged in front of the sorting queue. For each service flow, aggregation point 121 can record the sequence number k of the upstream packet that should currently be sent. If the sequence number of the first packet in the sort column corresponding to the service flow is equal to k , the first packet is sent and the sequence number k is incremented by one, and so on. If the sequence number of the first packet is not equal to k , a timer is started. If the timer expires, the sequence number of the first packet is still not equal to k , then all the packets in the sorting queue are sent.

FIG. 4 is a flowchart of a method for controlling a software definition network 100 according to an embodiment of the disclosure. FIG. 4 illustrates a processing flow of a downlink packet transmitted from the remote network 150 to the user equipment 140 in the above control method. At step 410, aggregation point 121 receives the downstream packet transmitted by remote network 150 to user equipment 140. In step 420, the aggregation point 121 selects one of the multiple routing paths for each downlink packet transmitted to the user equipment 140 according to the downlink packet transmission ratio between the plurality of routing paths to transmit the downlink packet to the user. Device 140. The controller 110 can determine the downlink packet transmission ratio according to the state of each routing path (for example, the available bandwidth), and transmit the downlink packet transmission ratio to the aggregation point 121.

At step 430, aggregation point 121 is the downlink packet plus the channel header corresponding to the selected routing path. If it is selected, it is a bypass route through the base station 131. The path, aggregation point 121 is the downlink packet plus the channel header of the LTE network. If the routing path through the access point 132 is selected, the aggregation point 121 is the downstream packet plus the channel header of the Wi-Fi network. The aggregation point 121 then transmits the downstream packet to the user equipment 140 via the selected routing path at step 440.

In step 450, the user equipment 140 receives the downlink packet, removes the channel header of the downlink packet, and transmits the data or message in the downlink packet to the corresponding application software. The user equipment 140 may set a sorting queue for each service flow to sort the packets of each service stream and then sequentially transmit them to the application software. The sorting queue of the user equipment 140 is similar to the sorting queue of the aggregation point 121, and details are not described herein.

FIG. 5 is a schematic diagram of a software defined network 100 in accordance with another embodiment of the present disclosure. The software-defined network 100 of FIG. 5 is the same as FIG. 1, except that the user equipment 140 stops using the Wi-Fi network to which the access point 132 belongs because it detects that the connection signal of the access point 132 is degraded. FIG. 6 is a flowchart of a method for controlling a software definition network 100 according to an embodiment of the disclosure. FIG. 6 illustrates the above process of deactivating a Wi-Fi network.

At step 610, the user equipment 140 sends an interface switch message to inform the controller 110 that the user equipment 140 will disable the network interface connecting the access points 132. In step 620, the controller 110 receives the interface switching message and modifies the routing rule of the aggregation point 121 to disable the routing path corresponding to the interface switching message (that is, the routing through the switch 122 and the access point 132). Path), and use the remaining routing path to transmit the downlink packet to the user equipment 140. In this embodiment, there are only two routing paths, so the subsequent downlink packets are all transmitted through the routing path of the base station 131. give away. At step 630, the controller 110 transmits a modification success message to the user device 140 to notify the user device 140 that the modification of the routing rule described above has been completed. At step 640, the user equipment 140 may stop transmitting the upstream packet over the Wi-Fi network of the access point 132. The uplink packets of the user equipment 140 are then transmitted to the aggregation point 121 through the LTE network of the base station 131.

FIG. 7 is a schematic diagram of a software defined network 100 in accordance with another embodiment of the present disclosure. The software-defined network 100 of FIG. 7 is the same as FIG. 1, except that the user equipment 140 is instead connected to the LTE network of the base station 131 and the Wi-Fi network of the access point 133. FIG. 8 is a flowchart of a method for controlling a software definition network 100 according to an embodiment of the disclosure. FIG. 8 illustrates a process of aggregation point conversion caused by a change in the network access status of the user equipment 140 of FIG. 7.

At step 810, user device 140 sends an interface update message to controller 110. This interface update message includes the latest network access status of the user device 140. In step 820, the controller 110 receives the interface update message, and selects one of the switches 121-124 as the user according to the network access status and the load of each of the switches 121-124 of the software definition network 100. A new aggregation point for device 140. In this embodiment, the new aggregation point selected by the controller 110 is the switch 123. Controller 110 also calculates a plurality of new routing paths between user equipment 140 and new aggregation point 123 in step 820. There are two new routing paths in this embodiment, which respectively correspond to the LTE network of the base station 131 and the Wi-Fi network of the access point 133.

At step 830, the controller 110 updates the new aggregation point 123, the original aggregation point 121, and the round-trip in the switch of the new routing path and the original routing path described above. The rules are to transfer the packet between the user equipment 140 and the remote network 150 using the new aggregation point 123 and the new routing path.

The calculation of the new aggregation point and the new routing path of step 820 and the calculation of the aggregation point and the routing path of step 230 are similar. The update routing rule of step 830 is similar to the setting routing rule of step 240, except that in step 830, the controller 110 also needs to remove the unwanted windings in the original aggregation point 121 and the original routing path. Send the rules.

At step 840, the controller 110 transmits an update success message to the user device 140 to notify the user device 140 that the update of the routing rules described above has been completed. At step 850, user equipment 140 may begin transmitting uplink packets. These upstream packets can be transmitted to the new aggregation point 123 through the LTE network of the base station 131 or the Wi-Fi network of the access point 133.

FIG. 9 is a schematic diagram of a controller 110 and a switch 121 in accordance with an embodiment of the present disclosure. The controller 110 includes a network interface 910 and a processor 920. The network interface 910 is coupled to the software-defined network 100 for transmitting and receiving packets to the controller 110. In the above embodiments, all data and messages transmitted and received by the controller 110 are transmitted through the network interface 910. The processor 920 is coupled to the network interface 910. In the above method flow, each step performed by the controller 110 is performed by the processor 920.

The switch 121 includes a network interface 930 and a processor 940. The network interface 930 is coupled to the software-defined network 100 for transmitting and receiving packets to the switch 121. In the above embodiments, all data and messages transmitted and received by the switch 121 are transmitted through the network interface 930. The processor 940 is coupled to the network interface 930. The above method flow Each step performed by the switch 121 is performed by the processor 940.

The rest of the switches 122-124 are constructed identically to the switch 121. Therefore, each of the switches 121-124 has the same function, and each of the switches 121-124 can be used as an aggregation point.

The embodiment of the present disclosure can select different switches for each user equipment as an aggregation point, so that a plurality of distributed aggregation points can be used to replace a single centralized aggregation point, and the disclosed embodiment can select neighboring according to the location of the user equipment. Or a lightly loaded switch as an aggregation point. In this way, the load of a single polymerization point can be effectively dispersed, so that the transmission performance bottleneck is not easily formed around each switch. The controller and user equipment in the above embodiments can adjust the packet transmission ratio between the routing paths to balance the network usage of each routing path to avoid network congestion. The above embodiment also provides a switching mechanism for the aggregation point and the routing path. When the user equipment changes the network access status due to poor signal or mobility, the network aggregation service can be uninterrupted.

The present disclosure has been disclosed in the above embodiments, but it is not intended to limit the disclosure, and any person skilled in the art can make some changes and refinements without departing from the spirit and scope of the disclosure. The scope of protection of this disclosure is subject to the definition of the scope of the appended claims.

100‧‧‧Software Definition Network

110‧‧‧ Controller

121~124‧‧‧Switch

131~134‧‧‧Edge device

140‧‧‧User equipment

150‧‧‧Remote network

Claims (14)

A control method for a software-defined network includes: receiving a registration message from a user equipment, wherein the registration message includes a network access status of the user equipment; and according to the network access status and the software definition The load of each switch of the network, selecting one of the switches of the software-defined network as an aggregation point of the user equipment; calculating a plurality of routing paths between the user equipment and the aggregation point, wherein each a routing path coupled to one of the plurality of network interfaces of the user equipment; and setting a routing rule at the aggregation point and each of the plurality of routing paths to bypass the user equipment and A packet between remote networks. The control method of claim 1, further comprising: assigning a network address of the user equipment and a network address of the aggregation point; and a network address of the user equipment and the aggregation point The network address is transmitted to the user equipment. The control method of claim 1, further comprising: determining a transmission ratio between the plurality of routing paths according to a state of each of the routing paths; and transmitting the transmission ratio to the aggregation point, The aggregation point selects one of the multiple routing paths for each downlink packet transmitted to the user equipment according to the transmission ratio to transmit the downlink packet to the user equipment. For example, the control method described in claim 1 of the patent scope further includes: Receiving an interface switching message from the user equipment, where the interface switching message corresponds to one of the plurality of routing paths; modifying a routing rule of the aggregation point to disable the routing path corresponding to the interface switching message And using the remaining routing path to transmit the downlink packet to the user equipment; and notifying the user equipment that the modification of the routing rule described above has been completed. The control method of claim 1, further comprising: receiving an interface update message from the user equipment; and selecting one of the switches of the software-defined network as the user equipment according to the interface update message. a new aggregation point; calculating a plurality of new routing paths between the user equipment and the new aggregation point; updating the new aggregation point, the original aggregation point, and the plurality of new routing paths and the foregoing plurality of windings And a routing rule in the switch of the sending path, to transfer the packet between the user equipment and the remote network by using the new aggregation point and the plurality of new routing paths; and notifying the user equipment of the foregoing routing The update of the rules has been completed. A packet processing method for a software-defined network includes: selecting one of the switches according to a network access state and a load of each of the plurality of switches of the software-defined network As an aggregation point; receiving, by the aggregation point, an uplink packet transmitted by a user equipment to a remote network; Removing, by the aggregation point, a channel header of the uplink packet, and then transmitting the uplink packet to the remote network; receiving, by the aggregation point, a downlink packet transmitted by the remote network to the user equipment; Selecting one of a plurality of routing paths of the user equipment to transmit the downlink packet; and adding, by the aggregation point, the channel header corresponding to the selected routing path to the downlink packet, and then transmitting The selected routing path transmits the downlink packet to the user equipment. The packet processing method of claim 6, further comprising: selecting, by the aggregation point, one of the plurality of routing paths according to a transmission ratio between the plurality of routing paths to transmit the downlink packet. The packet processing method according to claim 6, wherein each service flow between the user equipment and the remote network further includes: receiving, by the aggregation point, a plurality of uplink packets of the service flow; The aggregation point sorts the plurality of uplink packets according to the sequence numbers of the multiple uplink packets, and then sequentially transmits the multiple uplink packets to the remote network. The packet processing method according to claim 8, wherein the serial number is located in a channel header of the plurality of uplink packets. A controller for a software-defined network includes: a network interface coupled to the software-defined network to transmit and receive packets for the controller; a processor coupled to the network interface and receiving a registration message from a user equipment, wherein the registration message includes a network access status of the user equipment; the processor is based on the network access status and the software definition The load of each switch of the network, one of the switches that selects the software-defined network is used as an aggregation point of the user equipment, and calculates a plurality of routing paths between the user equipment and the aggregation point, where Each of the bypass paths is coupled to one of a plurality of network interfaces of the user equipment; the processor sets a routing rule at the aggregation point and each of the plurality of routing paths to bypass the A packet between the user equipment and a remote network. The controller of claim 10, wherein the processor assigns a network address of the user equipment and a network address of the aggregation point, and the network address of the user equipment and the aggregation point The network address is transmitted to the user equipment. The controller of claim 10, wherein the processor determines a transmission ratio between the plurality of routing paths according to a state of each of the routing paths, and transmits the transmission ratio to the aggregation point. The aggregation point selects one of the plurality of routing paths for each downlink packet transmitted to the user equipment according to the transmission ratio to transmit the downlink packet to the user equipment. The controller of claim 10, wherein the processor receives an interface switching message from the user equipment, the interface switching message corresponding to one of the plurality of routing paths; the processor modifying the aggregation point The routing rule is configured to disable the routing path corresponding to the interface switching message, and use the remaining routing paths to transmit the downlink packet to the user equipment, and then the processor notifies the user equipment of the routing rule. The modification has been completed. The controller of claim 10, wherein the processor receives an interface update message from the user equipment, and selects one of the switches of the software-defined network as the user equipment according to the interface update message. a new aggregation point, calculating a plurality of new routing paths between the user equipment and the new aggregation point, updating the new aggregation point, the original aggregation point, and the plurality of new routing paths and the foregoing plurality of a routing rule in the switch of the routing path to transfer the packet between the user equipment and the remote network by using the new aggregation point and the plurality of new routing paths, and then the processor notifies the user equipment The above update of the routing rules has been completed.