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New Member

Packet processing on VLAN interface

Hi All,

I have some missunderstunding about VLAN interface packet processing. Please confirm the patch:

1.IP Packet incoming on the vlan 10 access interface

2.Switch decapsulate the L2 header and check if it has dst MAC address in it's MAC table. In this example let's assume that this is a MAC address of the L3 interface for that VLAN

3.Packets go to the VLAN L3 interface (it's rate as incoming packet) and then router looks for the dst IP adrress to check on wich interface it should outbound.

4.Router change L2 src and dst address and send packet on sourced MAC interface

Is those steps are correct ?

In general I would like to know what exacly mean Input/Output rate on VLAN logical interface's. I assume that inboud rate is the traffic FROM the vlan X where interface VLAN belong and output rate is the traffic that is routed TO the VLAN X from other L3 interfaces. Also, when the traffic is only bridged - from one access port to other access port (or trunk) on same router the input/ouput rate on VLAN interface should not count.

Please help clarify


New Member

Re: Packet processing on VLAN interface

You are absolutely right, the counters are only incrementing if the packets hit the gateway, but when these packets moving from one access port to another within the same vlan they will not hit the gateway so it will not be counted

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