It depends.
http://kerneltrap.org/node/5607 gives part of the answer...
-Steve S.
> -----Original Message-----
> From:
owner-misc@... [mailto:
owner-misc@...] On Behalf
> Of Karsten McMinn
> Sent: Friday, April 25, 2008 7:39 PM
> To:
misc@...
> Subject: Re: OpenBSD isakmpd and pf vs Cisco PIX or ASA
>
> On Fri, Apr 11, 2008 at 9:13 AM, Matthew Dempsky <
matthew@...>
> wrote:
> >
...
> I've benchmarked PIX 515s running 7.2 code using stateful
> failover and the proprietary serial cable. Powering down
> the active firewall nets about 700-750ms of downtime consistently.
> How does carp fare?
