packet checksum

Hi !

Each time a packet pass through a firewall (forward rules), its checksum
is re-calculated by the kernel, thus killing the firewall performances.

Is there a way to deactivate this re-calculation ?

Thanks !

C.

C. wrote:

>
> Hi !
>
> Each time a packet pass through a firewall (forward rules), its checksum
> is re-calculated by the kernel, thus killing the firewall performances.
>
> Is there a way to deactivate this re-calculation ?

Don't use NAT? Because NAT changes the destination IP address the router MUST
recalculate the checksum. However, calculating a checksum is not very CPU
intensive, unless you are running on an old '386

> Thanks !
>
> C.
>

--
Phil Frisbie, Jr.
Hawk Software
http://www.hawksoft.com

> Don't use NAT? Because NAT changes the destination IP address the router
> MUST recalculate the checksum.

No NAT at this time, the firewall acts like a regular ethernet bridge.
The TTL must be decreased, therefore the checksum must also be
recalculated...


> However, calculating a checksum is not very CPU intensive, unless you are
> running on an old '386

Well...it seems to be quite intensive when Gigabit Ethernet NICs are in
use (I should have mentionned that before ), that's why I'd like to
get rid of checksum...

Any idea ?

Thanks

C.

C. wrote:

> Well...it seems to be quite intensive when Gigabit Ethernet NICs are in
> use (I should have mentionned that before ), that's why I'd like to
> get rid of checksum...
>
> Any idea ?
>

Checksums are part of the package. You can't get rid of them.

--

Fundamentalism is fundamentally wrong.

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