Spam now accounts for over 90% of all e-mails
New guidelines for how internet service providers should combat spam have been published.
The advice, from the Messaging Anti-Abuse Working Group (MAAWG) recommends ISPs use separate servers for received and forwarded e-mails.
It also recommends ISPs block the port - known as port 25 - through which spam travels.
Richard Cox from UK anti-spam group Spamhaus believes the guidelines could be implemented within the year.
"These are very significant recommendations and they are coming from a well-respected body so there is not much excuse for not following them," he said.
It is estimated that over 90% of all e-mail is spam.
Even if the guidelines are taking up by a majority of ISPs, experts admit it is unlikely that people will see a drastic reduction in spam any time soon.
"Some ISPs will always remain wide open even if we succeed in closing port 25," said Matt Sergeant, a senior anti-spam technologist with security firm MessageLabs.
"But that doesn't mean that it isn't worth doing. If we don't do it spam volumes will increase," he said.
The first of MAAWG's recommendations calls for a separation between original e-mails and those that are forwarded on.
"When mail is forwarded it is often the case that spam and viruses are also forwarded," said Mr Sergeant.
Making a distinction will make stop those sending e-mail from being associated with spam.
"It will give recipients the ability to recognise spam and reject it," Mr Cox added.
The second looks at the issue of so-called botnets - networks of computers that have been taken over by hackers to send malicious software and spam.
MessageLabs estimates that over 90% of spam is sent via botnets.
The idea of blocking port 25 is not a new one but it will gain new impetus now it has been officially outlined by MAAWG, thinks Mr Cox.
A number of ISPs in the US - from where historically the majority of spam originates - are already implementing the block.
But Mr Sergeant thinks spammers are bound to stay ahead of the attempts to limit their influence.
"They will have fewer ISPs to use but they will simply develop faster engines," he said.