Send Packets Using Native WiFi

There are two NICs in my computer, one is Intel Gigabit network Connection, the other is RT73 USB Wireless LAN card. Now I want to send my packets to some a specified destination PC. For simplicity,this packet just contains an Ethernet header and some unuseful data with total size 80. And the structure of this Header is:
typedef struct _TESTPROV_ETH_HEADER
{
UCHAR DstAddr[TESTPROV_MAC_ADDR_LEN];
UCHAR SrcAddr[TESTPROV_MAC_ADDR_LEN];
USHORT EthType;

} TESTPROV_ETH_HEADER;
And the value of EthType is 0x8e88.
I have a test and find that this packet could be sent outside using the Gigabit network card and here is the result captured by network monitor.

4 0.000000 [VMware, Inc. 81EB42 [00-0C-29-81-EB-42]] [VMware, Inc. 81EB42 [00-0C-29-81-EB-42]] EAPOL EAPOL:EAPOL-Start , Length = 515

While strangely, the USB wireless LAN card fail to send the same packets out. I am wondering maybe the format of packet is not suitable for native wifi. But I am not sure about that. Are there any factors may make this happen? And How can I do if I want to send this packet successfully using native wifi? Thanks.
Yaokee

Ethertype 0x8e88 is EAPoL, wi-fi stack recognizes it and handles in a
special way.
What is strange - why netwok monitor sees the packet length as 515, if the
total size is 80?

–pa

wrote in message news:xxxxx@ntdev…
> There are two NICs in my computer, one is Intel Gigabit network
> Connection, the other is RT73 USB Wireless LAN card. Now I want to send
> my packets to some a specified destination PC. For simplicity,this packet
> just contains an Ethernet header and some unuseful data with total size
> 80. And the structure of this Header is:
> typedef struct _TESTPROV_ETH_HEADER
> {
> UCHAR DstAddr[TESTPROV_MAC_ADDR_LEN];
> UCHAR SrcAddr[TESTPROV_MAC_ADDR_LEN];
> USHORT EthType;
>
> } TESTPROV_ETH_HEADER;
> And the value of EthType is 0x8e88.
> I have a test and find that this packet could be sent outside using the
> Gigabit network card and here is the result captured by network monitor.
> -----
> 4 0.000000 [VMware, Inc. 81EB42 [00-0C-29-81-EB-42]] [VMware, Inc. 81EB42
> [00-0C-29-81-EB-42]] EAPOL EAPOL:EAPOL-Start , Length = 515
> ----
> While strangely, the USB wireless LAN card fail to send the same packets
> out. I am wondering maybe the format of packet is not suitable for native
> wifi. But I am not sure about that. Are there any factors may make this
> happen? And How can I do if I want to send this packet successfully using
> native wifi? Thanks.
> Yaokee
>

I don’t know why the packet’s size is larger than 80. But know this packet could be sent out when using the real MAC address of the wireless NIC. Here is message captured by network monitor:
284 7.437500 [002586 EB7B0C] [USI 5B1430] EAPOL EAPOL:EAPOL-Start , Length = 515
more detail:
Frame: Number = 284, Captured Frame Length = 130, MediaType = WiFi
could someone explain this situation?