There is nothing magic in spam filtering. They either use some custom RBLs or combine standard RBLs with content filtering based on some open source software (most likely spamassassin). Even conservative RBLs classify 75-90% of email traffic as spam. Since ironport owns spamcop, then their RBL data can be based on spamcop reports. Spamcop is not conservative RBL. I think they even had page which stated that their RBL should be used only for tagging.
You paid 1.5M for dedicated spam filtering box which you could setup yourself. If your traffic is reduced, then their solution is based on RBL or some RBL data is integrated into firewall or you didn't use RBLs in the first place and relied only on greylisting/content filters. Or they offload email traffic to remote servers and only your own traffic is reduced. 2010.02.08 22:47 Scott Ryan rašė: > To handle over a billion mails a month and reduce bandwidth by about > 50-60% (in a country who's international bandwidth is limited compared > to rest of world) as well as severely reducing the load on the SAN and > mail storage environment - all in all it was about $1.5M. > > Turned out to be a no brainer. > > On Mon, Feb 8, 2010 at 8:49 PM, Hugo Monteiro <hugo.monte...@fct.unl.pt> > wrote: >> On 02/08/2010 07:39 PM, Scott Ryan wrote: >>> >>> I ended up handing the fight over to Ironport. Put in some Ironport >>> devices in front of my mail environment and ... >>> VIOLA! no more spam. >>> >>> >> >> >> Reputation filters .. isn't that a new fancy name for RBLs? Thanks but >> no >> thanks. >> >> Out of curiosity.. how much $/€/£ each, and how many did you need for >> your >> infra-structure? >> >> R's, >> >> Hugo Monteiro. >> >> -- >> fct.unl.pt:~# cat .signature >> >> Hugo Monteiro >> Email : hugo.monte...@fct.unl.pt >> Telefone : +351 212948300 Ext.15307 >> Web : http://hmonteiro.net >> >> Divisão de Informática >> Faculdade de Ciências e Tecnologia da >> Universidade Nova de Lisboa >> Quinta da Torre 2829-516 Caparica Portugal >> Telefone: +351 212948596 Fax: +351 212948548 >> www.ci.fct.unl.pt ap...@fct.unl.pt >> >> fct.unl.pt:~# _ >> >> > > > > -- > Scott Ryan > http://bonoboslr.wordpress.com/ >
