Re: Blocking traffic by Country to reduce spam

[Stephen Mullins <steve.mullins.work () gmail com>]

> From Wikipedia by way of Sophos:

"In terms of volume of spam: According to Sophos, the major sources of
spam in the fourth quarter of 2008 (October to December)
were:[20][46][47][48][49][50][51][52][53][54]

    * The United States (the origin of 19.8% of spam messages, up from
18.9% in Q3)
    * China (9.9%, up from 5.4%)
    * Russia (6.4%, down from 8.3%)
    * Brazil (6.3%, up from 4.5%)
    * Turkey (4.4%, down from 8.2%)

When grouped by continents, spam comes mostly from:

    * Asia (37.8%, down from 39.8%)
    * North America (23.6%, up from 21.8%)
    * Europe (23.4%, down from 23.9%)
    * South America (12.9%, down from 13.2%)"

Based on this information alone and simple logic (blocking entire
countries eliminates spam from being delivered from those countries) I
would say the answer is yes.

You need to be ready to white list foreign addresses in the countries
you are blacklisting as it is unlikely that nobody in your
organization will ever need to communicate with someone outside of the
U.S./U.K.

Steve Mullins


On Mon, Jun 22, 2009 at 10:38 AM, <paavan.shah () gmail com> wrote:
> Hello List,
>
> One of our clients is based in USA and has most of the business in USA and UK.
>
> To reduce spam we are planning to propose them a solution to filter traffic by country.
>
> We can add IP Blocks for USA and UK as a whitelist and allow only incoming access to those IP Blocks,everything else 
> is blocked.
>
> Has anyone implemented this change on their production networks?Has it been effective to reduce spam?
>
> Please share your views and experiences
>
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