[vpn-help] Windows 7 64bit Slow VPN

[Matthew Grooms]

On 2/14/2012 7:21 PM, Mark A. DeMichele wrote:
> Yes, that's the mode I'm using.
>

This improvement is most likely related to proper emulation of Large 
Segment Offload in 2.2.x.

What happens is this: A packet is sometimes send down the NDIS driver 
stack with the expectation that the adapter will handle a specific task 
on behalf of the OS to increase throughput. However, the VPN Client can 
intercept and process packets before they reach the adapter. In 2.1.7, 
the client doesn't emulate any bypassed hardware features, so the only 
option is to disable it in the adapter properties ( or experience awful 
throughput due to malformed packets ). The problem isn't reported very 
often as most people use a virtual adapter mode which doesn't claim to 
support any hardware acceleration. In 2.2.x, the client emulates most of 
the common task offload features to avoid these kinds of issues.

-Matthew