As much as client side technology has improved, the biggest boost to stopping spam has been at the server level.

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"These protocols alone are not effective in identifying spam because spammers are doing what they always have, adapting in order to circumvent measures aimed at stopping spam, " said Paul Judge, chief technology officer at CipherTrust.

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While the technique of routing mail via mail servers of net service firms might cause problems for those that use blacklists and block lists it did not mean that other techniques for stopping spam lost their efficacy too.

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The tools used to stop spam get in the way of stopping these messages precisely because they occupy that hard-to-define space between real junk and real messages.

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