Well, after many years with zero anti-spam technologies (and manual deletion of ~ 200 items a day) I decided it was time to move my mail host and implement anti-spam technologies.

Now I already have a home SAMBA server, running Debian, which also acts as a mini desktop. I decided to use this as my mail volume isn’t huge… I get ~20 valid emails a day, ~200-500 spams depending on the day of week really.

SpamAssassin looked to be the premier anti-spam solution out there for Linux, and I selected a Debian EXIM integration. Took a while to learn exim, but I’m now mostly impressed with the configuration. I’ve used dovecot as a IMAP server. All these are the standard Debian stable packages……

Basic procedure for me was I installed the packages - then I followed this guide and got a basic system up and running… and moved a “test” domain name to point inbound SMTP at the box so I could then fully test all the options and tune the anti-spam.

Tricks the above guide missed:

Using CPAN (perl -m CPAN -e shell) to install Net::DNS. Without this vital step Spamassassin missed out on ALL DNS tests, which are quite good for scoring.

Bayesian filtering.

• Set this up to use a system wide database, in a folder you control with world read/write access. The default isn’t right.
• You may wish to increase the default size of the bayes database. I increased mine 10 times.
• It seems to require 200 spams and 200 non-spams to be learnt before its operational - at first I did not realise this. I fed Bayes a folder of 2000 spams, and let it read my (already filtered of spam) archive of personal mails as non-spam (3400 items). This trained the spam filter quite well.. I used a variation of this script
• If you run sa-learn with -D for debug it does tend to show faults in your SA config.
• Increasing score of BAYES_99 for me at least results in better results.
• I’ve set up learn as spam folders in my mailfile, which is learnt and deleted every 6 hours (ie mails making it through SA I drag to this folder).

Setting SpamAssassin up is NOT easy, and requires a lot of tinkering to get runnign as you want (hence my playing with a test domain). Once complete however, its an brilliant system in my opinion at least.

Now its up and running, only 4 spams have hit my mailbox (though I’m still storing all spam - aim is to not store very high scoring spams in future, and only store “uncertain” results. Though right now, with ~5000 spams not hitting my mailbox I’m a happy bunny.

SpamAssassin is also available as a windows version I believe. For Exchange users with nothing else it may be worth a look.

I friend I met up with last week does not have Broadband at home via DSL or Cable. Nor do they use Wifi. They actually use a Vodafone 3G Datacard, providing 3Gig of data a month for a monthly fee.

All the UK carriers now I believe are doing some form of 3G datacard - but finally with decent usage limits (1 Gig being a minimal usable level per month) - and all for varying fees. The above example, in my friend, pays £45-50 a month for her 3G of data. But as she says, “I can use it anywhere” - but she says she will move to a cheaper provider when contract is up. Three now are I see doing same amount of data for £15 a month if tied to a 18 month contract and T-mobile do the same deal also I believe(but with free wifi access in their hotspots bundled). Which brings me to the point of this article:

If you can get 3Gig of data for £15 a month, providing 3Gig of data at up to 2.8Mbit a sec of bandwidth (assuming HSDPA) - why would you use a public hotspot in say Starbucks (which is probably uplinked to the net at a very similar speed)?

More to the point - you can use that data on the train, in places other than the hotspot - using it literally everywhere. The friend in question chatted to me using MSN - in a cab on the way to Heathrow - in a video call for example - impossible with Wifi.. and very impressive.

I also see that Three are even doing pay as you go data (at 10 pounds for the use of 1Gigabyte for 30 daysif the advert in todays paper is to be believed). The use of even 2-3 hours of wifi in many coffee shops would easily pay for 1 gig of data to be used in many coffee shops over the entire country. And with pay and go, theres no need to even be contracted, so this service could even be used by a foreign visitor…

Thus I believe that the days of coffee shops charging expensive rates for broadband access via wifi will soon be over (well assuming the coffee shop isn’t in underground with no signal).

This of course also applies to overcharging hotel chains - in Europe last year I got charged > £15 for 24 hours Internet access (and only for one device!) - now if I could get a pay-and-go sim and a hsdpa modem/3g card for the country being visited (or just take an unlocked one), why would I pay those prices?

Of course all this could lead to coffee shops and Hotels lead lining / filtering to stop 3g signal entering their premises…

I’ve had ADSL since around 2003 - initially with a 512K service, then 2Mbit, then MAX upon release, all via Andrews and Arnold (who incidentially provide a fine service or I would have moved ages ago).

Anyhow, this post is about my experience over the past few years since I moved into my new build house in  early ‘06 with Sync speeds and MAX .   Initially I was the only person in my street with ADSL and got a full 8Mbit sync - however as my two immediate neighbors got DSL, my sync dropped to a level of 6Mbit a few months upon moving in.
Yesterday one of the neighbors moved house and terminated their DSL as would be expected.    My sync as they moved out has now increased to 8Mbit!.     I believe the 2 things are related - and I’m now happy as I have full speed DSL at home.

Only downside is as the new neighbors move in, I expect I’ll get a drop in sync again..!

Anyone else had similar experiences?