Overview

The OVS control plane is developed in C. It empowers users to customize flow entry issuance when utilizing either open-source or custom OVS, ensuring seamless adaptation between the control plane software and the data plane.

Development of the OVS control plane is optional. By default, if no custom development is performed, the control plane supports a pre-defined set of keys and actions. See Table 1 and Table 2.

**Table 1** Supported DPDK keys
Issuance Condition	DPDK Key Type Name	Valid Field Type Description
The L3 protocol of the packet is IPv4.	RTE_FLOW_ITEM_TYPE_IPV4	IPv4 protocol field, which indicates the protocol type of the next layer.
		IPv4 sip field, which indicates the source IP address.
		IPv4 dip field, which indicates the destination IP address.
The L3 protocol of the packet is IPv6.	RTE_FLOW_ITEM_TYPE_IPV6	IPv6 protocol field, which indicates the protocol type of the next layer.
		IPv6 sip field, which indicates the source IP address.
		IPv6 dip field, which indicates the destination IP address.
The L4 protocol of the packet is TCP.	RTE_FLOW_ITEM_TYPE_TCP	TCP sport field, which indicates the source port.
The L4 protocol of the packet is TCP.	RTE_FLOW_ITEM_TYPE_TCP	TCP dport field, which indicates the destination port.
The L4 protocol of the packet is UDP.	RTE_FLOW_ITEM_TYPE_UDP	UDP sport field, which indicates the source port.
The L4 protocol of the packet is UDP.	RTE_FLOW_ITEM_TYPE_UDP	UDP dport field, which indicates the destination port.
The L2 protocols of the packet are Ethernet and VLAN.	RTE_FLOW_ITEM_TYPE_ETH	Ethernet eth_type field, which indicates the protocol type of the next layer.
		Ethernet smac field, which indicates the source MAC address.
		Ethernet dmac field, which indicates the destination MAC address.
The L2 protocol of the packet is VLAN.	RTE_FLOW_ITEM_TYPE_VLAN	VLAN vlan_tci (pri + cfi + vid) field. pri represents the 802.1p priority of the data frame. cfi indicates whether the MAC address is encapsulated in a standard format across different transmission media. vid indicates the ID of the VLAN to which the data frame belongs.
Default issuance	RTE_FLOW_ITEM_TYPE_PORT_ID	Source port of the packet.
VXLAN tunnel packet	RTE_FLOW_ITEM_TYPE_VXLAN	VXLAN tunnel layer vni field, which is the network identifier of the VXLAN.
The L4 protocol of the packet is ICMP.	RTE_FLOW_ITEM_TYPE_ICMP	ICMP type field, which indicates the message type. The type field and code field together identify the ICMP packet type.
		ICMP code field, which indicates the message sub-type. The type field and code field together identify the ICMP packet type.
		ICMP identifier field, which indicates the echo request corresponding to the echo reply.
The L4 protocol of the packet is ICMPv6.	RTE_FLOW_ITEM_TYPE_ICMP6	ICMPv6 type field, which indicates the message type. The type field and code field together identify the ICMPv6 packet type.
The L4 protocol of the packet is ICMPv6.	RTE_FLOW_ITEM_TYPE_ICMP6	ICMPv6 code field, which indicates the message sub-type. The type field and code field together identify the ICMPv6 packet type.

The issuance of the following actions is determined by the OVS and OpenFlow flow table configurations.

**Table 2** Supported DPDK actions
DPDK Action Type Name	Description
RTE_FLOW_ACTION_TYPE_COUNT	Collects hit statistics for flow entries.
RTE_FLOW_ACTION_TYPE_PORT_ID	Specifies the destination port of a packet, which indicates the output port for the packet.
RTE_FLOW_ACTION_TYPE_SET_IPV4_SRC	Modifies the source IP address in the IPv4 header.
RTE_FLOW_ACTION_TYPE_SET_IPV4_DST	Modifies the destination IP address in the IPv4 header.
RTE_FLOW_ACTION_TYPE_SET_IPV6_SRC	Modifies the source IP address in the IPv6 header.
RTE_FLOW_ACTION_TYPE_SET_IPV6_DST	Modifies the destination IP address in the IPv6 header.
RTE_FLOW_ACTION_TYPE_SET_TP_SRC	Modifies the source port in the TCP/UDP header.
RTE_FLOW_ACTION_TYPE_SET_TP_DST	Modifies the destination port in the TCP/UDP header.
RTE_FLOW_ACTION_TYPE_SET_MAC_SRC	Modifies the source MAC address in the Ethernet header.
RTE_FLOW_ACTION_TYPE_SET_MAC_DST	Modifies the destination MAC address in the Ethernet header.
RTE_FLOW_ACTION_TYPE_OF_POP_VLAN	Decapsulates VLAN tunnel packets.
RTE_FLOW_ACTION_TYPE_OF_PUSH_VLAN	Encapsulates VLAN tunnel packets.
RTE_FLOW_ACTION_TYPE_OF_SET_VLAN_PCP	Modifies the PCP field of VLAN packets.
RTE_FLOW_ACTION_TYPE_OF_SET_VLAN_VID	Modifies the VID field of VLAN packets.
RTE_FLOW_ACTION_TYPE_VXLAN_ENCAP	Encapsulates VXLAN tunnel packets.
RTE_FLOW_ACTION_TYPE_VXLAN_DECAP	Decapsulates VXLAN tunnel packets.
RTE_FLOW_ACTION_TYPE_SET_TTL	Sets the TTL field of IP packets.
RTE_FLOW_ACTION_TYPE_DEC_TTL	Decrements the TTL field of IP packets.

Parent topic: OVS Control Plane Programming