Protocol Packet Transparent Transmission in a VLAN

When the device is used as a gateway or a Layer 2 switch enabled with snooping functions such as DHCP/IGMP/MLD snooping, the device needs to parse and process the corresponding protocol packets. Protocol packets received by an interface are sent to the CPU for processing and the interface sends protocol packets without differentiating VLANs. If the preceding snooping functions are deployed, protocol packets from all VLANs are sent to the CPU for processing.

If the device is a gateway for some VLANs or snooping functions are deployed in some VLANs, the device does not need to process protocol packets from other VLANs. After the protocol packets in other VLANs are sent to the CPU, the CPU needs to forward them to other devices. This mechanism is called software forwarding. Protocol packet processing in software forwarding decreases the forwarding efficiency.

To address this issue, deploy protocol packet transparent transmission in VLANs where protocol packets do not need to be processed. This function enables the device to transparently transmit the protocol packets from VLANs to other devices, improving forwarding speed and efficiency.

Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730-H, S6730S-H, S6730-S, and S6730S-S support this function.