On 9 Jun 2011, at 18:16, Mikhail Lischuk wrote:
>
>
> On Thu, 09 Jun 2011 16:38:10 +0000, W B Hacker wrote:
>
>> Smart
> folks, and they'll probably not be among the 18 Ukrainian .tld I hard
> block who DON'T try to curb the worst of their WinBots.
>
> Sorry for
> off-topic posting, but let me clarify a little about Ukrainian ISPs:
> most of them have a marketing approach of "providing clean unfiltered
> Internet" to their clients, that's why they don't block 25 port. The
> largest cable and ethernet ISPs that come to my mind do not filter 25
> port.
>
> Second - if you block 25 port, it's a good approach to provide
> some kind of smarthost for your clients. Which will be in turn used by
> bots in all ways they want and smarthost will be blacklisted very often
> - maybe sometimes entire subnet. Besides if you implement some ways of
> blocking problem clients on your smarthost, you will greatly increase
> load average for your helpdesk.
>
> So, blocking 25 port is a good
> approach for ISP, but it will not make them spam- or problem-free.
That's true, but when an ISP blocks outbound port 25, two advantages are gained:
1. The ISP can spot, and deal with customers who are sending spam.
2. If the ISP doesn't do that, then the recipients can deal with the ISP instead of the ISP's customers. That's easier because there are fewer people to deal with, and they should have better technical knowledge.
> --
>
> With Best Regards
> Mikhail Lischuk [1]
>
> ITX Ukraine
>
>
>
>
> Links:
> ------
> [1] mailto:mlischuk@itx.com.ua
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