--On 8 January 2008 08:10:57 +0900 Michael Heydon <michaelh@???>
wrote:
> Ian Eiloart wrote:
>> I've seen several instances over the past few years where I've had to
>> disable user accounts here because of backscatter. This isn't simply a
>> theoretical problem.
>>
> Out of curiosity, what percentage (roughly) of this backscatter was
> proper bounce messages and what percentage was OoO replies?
0% was proper bounce messages. None of the bounces went to the originator
of the message.
I don't know the precise answer to the question. However, I do know that in
some instances it's been sufficient to block messages with empty
return-path, in other instances the majority of the messages haven't had
empty return-paths.
However, I also know that there are many sites out there that don't use
empty return-paths for non-delivery bounces!
> As I mentioned in an earlier message, I have had my address spoofed a
> couple of times and the 2-3 OoO replies I recieved were buried amongst
> several hundred bounces.
Yes, that can happen. However, as people are increasingly using rejection
rather than bouncing, the proportion of OoO replies will increase.
> *Michael Heydon - IT Administrator *
> michaelh@??? <mailto:michaelh@jaswin.com.au>
>
--
Ian Eiloart
IT Services, University of Sussex
x3148
