Re: NDIS IM Layering

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"Anton Bassov" <AntonBassov@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message news:6D79BA59-382C-4918-B738-2B808429CC22@xxxxxxxxxxxxxxxx
In practice, I was able to install the WDK sample PassThru and our own
driver which is based on PassThru with no observable problems. Both drivers
have their FilterClass specified as failover in their respective INF files.

Am I misunderstanding something here? Is the documentation making a
recommendation instead of stating policy?

As you have experimentally established, this is just one more MSDN claim
that proved to be false, at least in respect of failover drivers. Another
similar claim can be found in NDIS 6 documentation - MSDN claims that you
cannot have more than one modifying LWF in the same stack, and this claim is
false as well.....

I believe that you can read this claim a little differently.

In particular, you can only have one instance of your own modifying LWF on the same stack. For example, if you have a LWF that can bind to 802.3 and WLAN, then it will bind to one or the other but not both. In this case, the modifying driver will probably bind as 802.3 above the Microsoft Native Wi-Fi driver but will not bind a second time below the Native Wi-Fi filter.

A modifying filter setup to bind to 802.3 and WLAN will behave differently and will, in fact, bind itself twice on the same stack.

Agreed that the doc isn't crystal clear, but sometimes you have to experiment a little to find what they really meant.

Thomas F. Divine


Anton Bassov

"tnili" wrote:

According to the WDK documentation, you cannot have more than one NDIS IM
driver of a particular FilterClass (scheduler, loadbalance, failover) in a
stack. This is found under the topic "Filter Intermediate Driver
Installation (NDIS 5.1)".

In practice, I was able to install the WDK sample PassThru and our own
driver which is based on PassThru with no observable problems. Both drivers
have their FilterClass specified as failover in their respective INF files.

Am I misunderstanding something here? Is the documentation making a
recommendation instead of stating policy?




.

Relevant Pages

  • Re: NDIS IM Layering
    ... IM driver is often installed on systems that have VPN products installed, ... can be controlled by changing the FilterClass value in the protocol inf. ... scheduler - this makes the IM go higher in the stack. ... Installation ". ...
    (microsoft.public.development.device.drivers)
  • Re: NDIS IM Layering
    ... IM driver is often installed on systems that have VPN products installed, ... my product I need my IM to always be at the top so I have set FilterClass ... scheduler - this makes the IM go higher in the stack. ... Installation ". ...
    (microsoft.public.development.device.drivers)
  • Re: NDIS IM Layering
    ... have their FilterClass specified as failover in their respective INF ... cannot have more than one modifying LWF in the same stack, ... then it will bind to one or the other but not both. ... modifying driver will probably bind as 802.3 above the Microsoft Native ...
    (microsoft.public.development.device.drivers)
  • NDIS IM Layering
    ... you cannot have more than one NDIS IM ... This is found under the topic "Filter Intermediate Driver ... have their FilterClass specified as failover in their respective INF files. ...
    (microsoft.public.development.device.drivers)
  • [Q]FilterClass and Layering
    ... Is there a way to have an NDIS IM driver load at the bottom of the driver ... Define a proprietary FilterClass in my .inf ... MyClass after failover. ... the installer could call the appropriate ...
    (microsoft.public.development.device.drivers)