how to recognized Sending Packet in intermediate driver mux ?

Hi Everyone,

My first intention is implement n-to-one using mux.sys,for now I understood how to recognize received packet base on DstMac in PtMatchPacketToVElan and Calling NdisMIndicateReceiveNetBufferLists with pVElan->MiniportAdapterHandle for virtual adapter.

but I confuse how to recognized Sending Packet,Whether or not as same as Protocol’s receive did by DstMac to recognize extracting from NBL in miniport’s MPSendNetBufferLists to recognize virtual adapter or real adapter ?

Moreover, Can I use certain field of NBL to mark it such as OOB struct relative to NdisPacketOobOffset,etc…

Thanks