----- Original Message ----- From: "Loris Degioanni" <[EMAIL PROTECTED]>
To: <winpcap-users@winpcap.polito.it>
Sent: Tuesday, February 15, 2005 7:37 AM
Subject: Re: [WinPcap-users] Generic and specific NDISWAN interfaces in WinPcap 3.1 beta 4?
Guy Harris wrote:
> Somebody trying to capture on a serial port in Ethereal sent a long
note about that to the Ethereal list:
>
> http://www.ethereal.com/lists/ethereal-users/200502/msg00140.html
>
> It says:
>
>> 5) Because Windows PPP support is new, there is nothing about it in
>> the Help portion of Ethereal (Live Preserver Icon) or in the online
>> hypertext Help or online PDF Help file. I have attached some screen
>> captures which show that the PPP adapter doesn't show up as available
>> until the computer has established a dial-up connection with the
>> internet. At first all that showed up was "Generic NdisWan adapter:
>> \Device\NPF_GenericNdisWanAdapter". However I was able to capture my
>> dial-up conversations with my internet ISP using this Generic Ndis Wan
>> adapter. After I established the dial-up connection an additional
>> adapter showed up "WAN (PPP/SLIP) Interface:
>> \Device\NPF_{F37D0895-3FB0-4946-89D1-42FE988DBA90}". I reloaded a fresh
>> image of Win 2K and verified that the key
>>
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Tcpip\Parameters\Interfaces\{F37D0895-3FB0-4946-89D1-42FE988DBA90}
>> was present prior to loading WinPcap and Ethereal. It was. This raises
>> the question of why WinPcap can't find it until going online and
>> establishing a dial-up conncection and what the differences are, if >> any,
>> between the two adapters.
>
>
>
> and shows a "before going online" image:
>
> http://www.ethereal.com/lists/ethereal-users/200502/gif00006.gif
>
> with only "Generic NdisWan adapter:
\Device\NPF_GenericNdisWanAdapter" and an "after going online" image:
>
> http://www.ethereal.com/lists/ethereal-users/200502/gif00003.gif
>
> which shows that interface *and* a "WAN (PPP/SLIP) Interface:
\Device\NPF_{GUID inserted here}" interface.
>
> I assume that the latter gets instantiated when an actual PPP
connection is set up. I assume that he expected an interface that explicitly mentioned PPP to show up, but was presumably pleasantly surprised to find that he can capture on the generic interface.
>
> Is there any reason not to tell people to capture on the generic
interface and ignore any specific interfaces that show up after you connect?
The reason why we added the fake GenericNdisWanAdapter interface is that some users complained about not being able to capture before the instantiation of a PPP connection. In fact, the connection is present in the registry *before* calling the phone number, but the IP Helper API shows it (and WinPcap is allowed to open it) only *after* doing that.
Moreover, the Generic Ndiswan adapter is available before a connection is established, but it does not have any IP address associated. The IP addresses are associated to the specific interfaces that are available after the connection is established.
Actually, I think that a better name (like GenericPPPAdapter) could be useful, since many people don't know understand NdisWanAdapter mean.
If the other developers agree on this, I can change the code with the new name.
This is a good idea. I only want to check if the WanAdapter supports PPP connections only, or other ones, as well (like VPNs and SLIP, if there is still someone using SLIP...).
Have a nice day GV
Loris
================================================================== This is the WinPcap users list. It is archived at http://www.mail-archive.com/winpcap-users@winpcap.polito.it/
To unsubscribe use mailto: [EMAIL PROTECTED]
==================================================================
================================================================== This is the WinPcap users list. It is archived at http://www.mail-archive.com/winpcap-users@winpcap.polito.it/
To unsubscribe use mailto: [EMAIL PROTECTED]
==================================================================
