Small businesses 'fall into spam filtering's black hole'

Small businesses and mum-and-dad users fall into a ‘black hole’ when using spam-filtering solutions, according to data security expert Peter Stewart.

He says the filtering techniques that most anti-spam vendors deploy work well enough for computer savvy users and larger organisations whose technical staff have the time and patience to adjust and balance their filters, but small businesses usually lack the time, expertise and resources to tackle the vagaries of spam filters.

Stewart, who is CIO of TotalBlock Pty Ltd, says: “If users set the spam filter too tight, they lose ‘wanted’ emails to false positives – legitimate messages the filters class as spam. If they loosen the filters, they receive shoals of spam.”

He says most mum-and-dad users usually accept their default filter setting, and input from TotalBlock users suggests that this is too lax in most cases, plaguing the users with far too much spam.

Home user Paul Hunter has the expertise to deal with spam since he is a former senior executive with IBM. He drew the line after receiving 20-30 junk emails per day despite using BigPond’s anti-spam service, and switched to the TotalBlock anti-spam solution which uses challenge-response techniques rather than filtering.

Likewise the Managing Director of B&C Mailing, Australia’s oldest mailing house, was receiving 60 spam emails a day despite using a security management solution from CA. B&C Mailing also turned to the challenge-response solution.

So did businessman Richard Newton, CEO of Videowall Pty Ltd, who had been receiving about 300 spam emails a day in his in-box, despite using Microsoft’s anti-spam tool.

“Immediately, all three eliminated practically all unwanted email and missed no legitimate email messages,” says Peter Stewart.

Challenge-response works by blocking all machine-generated spam. TotalBlock builds a list of acceptable incoming email senders, first adding names from the user’s address book, then adding addresses from all outgoing emails. TotalBlock replies automatically to emails from anyone who is not on the allowed list, sending back a simple challenge. Once legitimate senders respond to the challenge, they are added to the allowed list for all future communication. This authorisation process halts the flood of emails from the drone machines that spew out huge volumes of spam.

According to Stewart, the often perceived downside to challenge-response is the reluctance of legitimate email senders to respond to a challenge. A survey of TotalBlock users found that about 80 per cent of legitimate emailers will respond to a challenge. For the remaining 20 per cent, TotalBlock users are able to check a Control Panel and authorise these personally.

However, challenges to legitimate emailers are few and far between. Almost all are already on the user’s list of acceptable email sources. Because outgoing email addresses are added automatically to the approved list, there are just two instances where legitimate incoming spam is challenged.

The first relates to email from unexpected but welcome sources. The second concerns recipients of the challenge-response user’s outgoing email, who choose to reply from a different email address.

TotalBlock customers can use the system’s online Control Panel to free these messages. They can also authorise domain names so that if a firm acquires new business from a firm called XYZCo, incoming emails from all staff at XYZCo are pre-authorised. Similarly, email services like online newsletters can be authorised in advance.

Peter Stewart has a stock reply to critics who claim people will not respond to a challenge: "If you knock on someone’s door and a voice says: ‘Who's there?’ do you walk away?”

He adds: “In my view, users continue to pay the price for spam-filtering vendors’ reluctance to adopt new technology. There is a delay in the market’s reaction because the cost of anti-spam solutions is being buried along with anti-virus technology, so people are not generally aware of the individual costs.

“Filtering and quarantining systems are constantly viewing and assessing the millions of messages that are flying around out there to determine if they are spam; it's nothing but a catch-up game in which the user pays.”

Stewart believes that vendors are reluctant to support challenge-response because it represents an alternative to an approach that creates ongoing revenue for them. Their solutions continue to investigate spam messages and update filters to defend against them, in a time-consuming and ultimately expensive process.

He says: “Only when email administrators’ frustration peaks will they turn to outsourcing, or to an alternative. When they seek an alternative, they often embrace challenge-response solutions.”

About TotalBlock

TotalBlock - www.totalblock.net - is an Australian-developed anti-spam solution that also guards against network overloads caused by storming, harvesting and denial-of-service (DoS) attacks. It works by blocking ALL machine-generated unwanted email, using a challenge-response technique rather than commonly used filtering. TotalBlock builds a list of acceptable incoming email senders, using a customer’s address book as well as replying automatically to any emailers who are not on the allowed list, and no further emails are challenged. The reply contains a simple action that, when followed, adds the sender to the allowed list. The action can be as simple as replying to the challenge. Since this authorisation process requires human intervention, it bypasses drone machines that spew out huge volumes of spam. The TotalBlock solution also features a free Webmail service.

For more information

Peter Stewart TotalBlock Pty Ltd Tel. 61-2-9437 9800 Email: pstewart@totalblock.net