There are legitimate ways that follow the letter of the RFC to prevent spam over SMTP (greylisting, etc.), or to overlay sender/server validation on top of it (SPF, etc.), but most of these lessons aren't cross applicable to XMPP
Sure, Google could spend a lot of time trying to come up with a technological solution that doesn't break federation (except for in spam cases), but it would be difficult to do on a service that fundamentally doesn't make money.
This sounds like blog trackback all over again - useful, a nice idea, but nearly worthless once spammers figure out how to pee in the communal pool.
Sure, Google could spend a lot of time trying to come up with a technological solution that doesn't break federation (except for in spam cases), but it would be difficult to do on a service that fundamentally doesn't make money.
This sounds like blog trackback all over again - useful, a nice idea, but nearly worthless once spammers figure out how to pee in the communal pool.