Arun Raghavan wrote:
>> We could use such an identifier to identify repeated submissions
>> (users should send in more up to date again later) and handle
>> some kind of "database pollution" attacks.  We wouldn't catch
>> attackers that change their MAC before submission.
> 
> Not sure how you can deal with this. How does Smolt or Debian's thing
> deal with it?

About Debian popcon:

The file

  /etc/popularity-contest.conf

contains a key MY_HOSTID which is initialized during package
installation through this code:

  generate_id() {
    if [ -x /usr/bin/uuidgen ] ; then
      MY_HOSTID=`uuidgen | tr -d -`
    else
      MY_HOSTID=`dd if=/dev/urandom bs=1k count=1 2>/dev/null \
          | md5sum | sed 's/  -//'''`
    fi
  }

The result is a 32 digit hex string.  On submission, data for that
host ID is replaced by the new set of data.



Sebastian