Spam blocking
Spam blocking is due for an improvement.
On some days, about 80% of the received mail concers sexual ‘enhancement’ (where I surely doubt women would really like it) in any form, medication I don’t need, other attractions, casino’s – and all kinds of unwanted stuff. And that’s just the part that gets through, a similar amount is kept out for different reasons: invalid domains, bad addresses, blocked domains…
So more control is needed on contents and headers, and this product from Process software can be used under the hobbyist license scheme.
I got a license a week ago but Outlook ruined it, nevertheless I installed the stuff but didn’t get it running. Today I got the new license, I re-considered the configuration and launched it.
Originally, as is stated in the documentation, I configured PMAS to listen on port 25 – the default SMTP port, and had to locate the regular service on another one. That is not that easy on OpenVMS’s TCPIP: the part in TCPIP$CONFIG that creates the service needed to be extracted and altered. That works, but I’m not really satisfied with that. I could instead hack the commandprocedure – but that could blow the whole system and that was not exactly what I have in mind.
It isn’t needed anyway. Since incoming mail from the Internet will arrive on the firewall for port 25, I can redirect everything that enters the network on that port to another port on Diana so the new spam-filtering service can intercept the message, press it through the filter and deliver the message on the normal SMTP port or discard it, depending on the outcome of the filter.
This has at least one big advantage: It’s just the firewall rules to be changed: close the original port 25 and enable the redirection to the PMAS port. When it fails, just restore the firewall and it”s done.
Secondly, it makes it qiute easy to test the product on the LAN without interfering with the regular mail: as long as I’m not finished, regular mail will continue to be delivered. It’s just a second path, usable on the local LAN.
In the end, I may have to do some re-configuration on the regular service but that’s minor.
Another thing to consider: AntiVirus.
It is possibe to screen incoming mail on Windows/Linux virusses as well. PMAS has a built-in facility for Sophos but they don’t offer hobbyist licences and is quite expensive – so I may have to turn to Clamav – freeware AND available on VMS, but probably it cannot be intgegrated like Sophos is. That’s a future thing…
Now the problem is merely a recall of the SMTP protocol, to test it with plain TELNET…
Don’t bother to try. The configuration on the outside hasn’t changed yet 🙂
