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what is spam or junk email?

Spam or junk email commonly refers to unsolicited commercial email messages. Almost every email users nowadays are being driven crazy by junk emails, primarily due to the following nature:

  • unsolicited, mostly we never opted in any of the spammers' list
  • offensive content, like indecent and obscene services and products
  • false sender identity
  • inability to opt-out of the mailing list
  • come with misleading information, subject lines and headers
  • come in big quantity on a daily basis
  • potentially with dishonest and deceptive purposes, like scams and phishing
  • potentially carry viruses
  • cause more time for us to identify genuine emails
  • cause more time spent to download unnecessary junk emails

Do you know that 100 known spam operations are responsible for 80% of your spam?


is it possible to completely stop junk emails?

Unfortunately, there is no way to completely block junk mails. However, with both legislative and technological approaches, we may be able to reduce a substantial number of spammers who blatantly spam almost every email user in the world.

Besides, some prudent practices could also safeguard your email accounts from junk email attacks for a relatively longer period of time:

  • use separate email accounts for private and public purposes, make sure that you only hand out your email account information to trusted party, or at worst, give away some web-based email accounts that you could create and discard easily.
  • if possible, do not open any of the junk emails, as they may contain some scripts to verify that your email address is valid and that you are reading the content. A simple trick to achieve this is by embedding a link or image inside the junk email pointing to their server with your email address as a parameter being passed back.
  • do not easily trust the unsubscription links or URLs listed inside any junk emails or spams that you never opted-in. They may be at best a mechanism to confirm that your email address is valid and continue to send you more junk emails later.
  • do not publish your email address publicly, especially inside the signature of your mail when you are sending any messages to public newsgroups or forums. Spammers love this piece of information as they have some simple automated bots to scour and extract these email addresses from public newsgroups and forums. If necessary, simply modify your email address to be human understandable text, such as, instead of, write it in such a way "myemail at domain dot com" or "".


stop junk emails with legislation?

Several countries in the world have bitten the bullet to enact relevant anti-spam/ anti-junk-email laws, which include the US, UK, Australia, South Korea and others. Arguably, these anti-junk-email laws have failed most of the expectations.

The biggest loophole behind this approach is that those anti-junk-email laws are not enacted in every country in the world, which allows major spammers to shift their base to other more lenient countries to continue their cash-making business.

On the other hand, legislative approach has to consider legitimate online email marketeers, who have been running direct email campaigns to deliver effective means of marketing products and services to a particular group of audience. Hence, these anti-junk-email laws could not simply outlaw every act of sending email messages that contains marketing information.

In view of this, technological approaches would be a better solution to stop junk emails.


stop junk emails with technology?

Spamming or the junk email problems arise out of the abuse of Internet technology, or specifically the underlying SMTP protocol. Fortunately, the solutions to stopping or minimizing junk email problems can also rely on the Internet technologies.

At present moment, various attempts to stop junk emails are beginning to emerge, but none of them seems to be the holy grail of stopping junk emails yet:

Technology framework. New standards like Sender Policy Framework, Caller ID and DomainKeys are making inroads to providing the ultimate solution of stopping junk emails. However, until the standards are finally agreed upon by all the major players and server implementers, we will still have to rely on other technological approaches to stop junk emails.

Server side filtering. This approach is becoming more and more popular, at least until before the above mentioned technology frameworks are to be finalized. Many ISPs and email servers are starting to support statistical filtering called Bayesian filters coupled with external DNSBL servers to stop junk emails.

The best thing about this approach is that junk emails get rejected or deleted or categorized into folders when they arrive at your email account. Those Bayesian filters are first fed with numerous junk emails to raise its effectiveness in identifying junk emails. And as you may have guessed, the effectiveness of these Bayesian filters improves over time, when more junk emails are being processed. On the down side, you may not even know that sometimes some genuine emails which are trying to reach you get deleted! Which means that if your friend's email content is deemed to be matching the spam patterns, you will know about it only if your friend calls you up to complain why you are not replying his/ her message.

Another approach is what we call Challenge and Response method. With this method, an email arrives at the server and is being put into custody. At the same time, the server is sending a notification mail to the sender requesting for acknowledgement that he/ she did send the mail, and of course, his/ her email address must be valid in order to receive this notification mail. After satisfactory acknowledgement from the sender, then only will the email be transferred to the recipient's email account.

Client side filtering. This approach might or might not use Bayesian filters. Most of the people go for this approach if they wish to avoid the problems associated with the server side filtering, i.e.

  • not knowing if any of the genuine emails get deleted on the server

However, if the anti-junk-email client uses Bayesian filters, junk emails are still downloaded onto local PC for further processing. Hence, resulting in the inevitable wastage of bandwidth. Consequently, to effectively stop junk emails at email server with this approach, perhaps a better way is to apply the combination of external DNSBL servers, black and white list as well as predefined filters. This could potentially help identify most of the junk emails while still preserving time and money on unnecessarily wasted bandwidth.