Method and apparatus for datacenter congestion control based on software defined network

A congestion control apparatus based on a software defined network (SDN), which is applicable to an SDN controller, comprising:

• a message obtaining module configured to obtain a packet-in message sent by a switch;
• a message determining module configured to determine a data packet included in the packet_in message, trigger a first control module when the data packet is a handshake information SYN packet for requesting to establish a new transmission control protocol (TCP) connection, trigger a second control module when the data packet is a first FIN packet for responding to disconnection of an established TCP connection corresponding to the packet in message in the network, and trigger a third control module when the data packet is a second FIN packet for requesting to disconnect the established TCP connection corresponding to the packet_in message in the network;
• the first control module is configured to perform a first congestion control processing for the network where the SDN controller is located based on a topological structure and link information of the network;
• the second control module is configured to perform a second congestion control processing for the network based on the link information;
• the third control module is configured to delete information of the established TCP connection stored in a database and corresponding to the data packet, wherein the database is used to store information of the new and the established TCP connections;
• the first control module is further configured for:
• extracting information of both communication parties from the SYN packet, wherein the information of both communication parties includes:
• an IP address of a sender, a port address of the sender, an IP address of a receiver and a port address of the receiver;
• determining path information of data flows between the sender and the receiver based on the topological structure and target information, wherein the target information includes:
• an ID of the switch, a input port number of the switch and information of both communication parties;
• storing the target information and the path information of the data flows into the database;
• allocating bandwidth for each of the data flows based on the link information and the path information of each of the data flows currently stored in the database;
• calculating a target window value of a receiving window for each of the data flows based on the bandwidth allocated for each of the data flows;
• for each of the data flows, generating a target flow table for the data flow, and forwarding the target flow table to a target switch corresponding to the data flow, wherein the target flow table for the data flow is used to update a size of the receiving window of the data flow to the calculated target window value for the data flow;
• wherein the allocating bandwidth for each of the data flows based on the link information and path information of each of the data flows currently stored in the database, comprises:
• obtaining target link information of each target link in the topological structure through statistics based on the link information and the path information of each of the data flows, wherein the target link is a link of a data flow having not been allocated with bandwidth, and the target link information of each target link includes:
• an available bandwidth of the target link and the number of data flows flowing through the target link and having not been allocated with bandwidth;
• determining among the target links, a most congested target link as a to-be-allocated link based on the target link information of each target link;
• allocating available bandwidth of the to-be-allocated link for a to-be-allocated data flow of the to-be-allocated link, wherein the to-be-allocated data flow is a data flow flowing through the to-be-allocated link and having not been allocated with bandwidth;
• updating link information of a link through which the to-be-allocated data flow flows, and returning to the step of obtaining target link information of each target link in the topological structure through statistics based on the link information and the path information of each of the data flows, until there is no target link in the topological structure.