[Operators] DNSBLs

[Sean Dilda]

Norman Rasmussen wrote:
> I was under the impression the DNS block lists don't work well anymore 
> (too many false positive, not enough true negatives)

DNS block lists are commonly used by many organizations and large 
companies.  Often they're used as one of several factors in deciding if 
the email received is spam.

> 
> XMPP validates the sending server via tls and/or dns (dial-back), so it 
> removes many of the unauthenticated problems of SMTP.  XMPP are also 
> working on allowing servers to inter-operate (XEP-0158, XEP-0159 and 
> XEP-0161) to help block clients clients that are spamming.

XEP-0158 doesn't help an individual account (or rogue jabber server) 
sending out spam to users instead of chat rooms.

XEP-0159 and XEP-0161 are listed as deferred and not to be implemented. 
  Do they really count for this conversation?