Flow transmission

A software defined network (SDN) controller for controlling flow transmission in an SDN virtualized network, comprising:

• a processor;
• and
• a non-transitory machine readable storage medium storing instructions executable on the processor to:
• receive a packet related to flow that is uploaded from a first virtual switch (vSwitch) that is part of a first physical server;
• and
• if a source address and a destination address of the packet related to flow belong to different physical servers, distribute a source flow table entry to the first vSwitch, the source flow table entry to cause the first vSwitch to,
• for a traffic packet whose destination address matches the destination address of the packet related to flow, encapsulate the traffic packet into an encapsulated packet having double layer virtual local area network (VLAN) tags;
• including an outer layer VLAN tag of a service VLAN where a physical network card of the first physical server is located, an inner layer VLAN tag of a customer VLAN where the source address is located, an outer layer source medium access control (MAC) address of the first vSwitch that is connected to a source host having the source address, and an outer layer destination MAC address of a second vSwitch connected to a destination host having the destination address, and forward the encapsulated packet from a port of the first vSwitch leading to the physical network card of the first physical server to cause the encapsulated packet to be sent to the second vSwitch and
• receive, from the first vSwitch, a further traffic packet;
• responsive to determining that the destination MAC address of the further traffic packet is a flag MAC address of a gateway, send, to the first vSwitch, a further source flow table entry with a MAC address substituted with the flag MAC address, to cause the first vSwitch to, if the destination MAC address of the further traffic packet is the flag MAC address, substitute the flag MAC address in the further traffic packet with a MAC address corresponding to a destination IP address.

A non-transitory machine-readable storage medium comprising instructions executable on a first physical server to:

• send, by a first virtual switch (vSwitch) on the first physical server to a SDN controller, a packet related to flow;
• receive, by the first vSwitch from the SDN controller, a source flow table entry responsive to the SDN controller determining that a source address and a destination address of the packet related to flow belong to different physical servers comprising the first physical server and a second physical server;
• for a traffic packet whose destination address matches the destination address of the packet related to flow, encapsulate, by the first vSwitch, the traffic packet into an encapsulated packet having double layer virtual local area network (VLAN) tags, the encapsulating comprising including, in the encapsulated packet, an outer layer VLAN tag of a service VLAN where a physical network card of the first physical server is located, an inner layer VLAN tag of a customer VLAN where the source address is located, an outer layer source medium access control (MAC) address of the first vSwitch that is connected to a source host having the source address, and an outer layer destination MAC address of a second vSwitch connected to a destination host having the destination address;
• forward the encapsulated packet from a port of the first vSwitch leading to the physical network card of the first physical server to cause the encapsulated packet to be sent to the second vSwitch;
• and
• receive, by the SDN controller from the first vSwitch, a further traffic packet;
• responsive to determining that a destination MAC address of the further traffic packet is a flag MAC address of a gateway, send, by the SDN controller to the first vSwitch, a further source flow table entry with a MAC address substituted with the flag MAC address;
• and
• if the destination MAC address of the further traffic packet is the flag MAC address of the further flow table entry, substitute the flag MAC address in the further traffic packet with a MAC address corresponding to a destination IP address of the destination host.