The best replacement for ironport is websense.

The best alternatives to ironport are rated as following:
★★★★★  websense
★★★★★  barracuda
★★★★  ironmail
★★★★  postini
★★★★  bluecoat
★★  proofpoint
★★  fortimail
★★  spamassassin
★★  scansafe
★  brightmail
★  messagelabs
  tumbleweed
  fire eye

Your alternative for ironport is not listed? Suggest!
Speaking about ironport, one probably shouldn't forget about wccp.

Other search terms related to ironport and their ratings are:
★★★★★ wccp
You have in mind a companion for ironport and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of ironport in all years. Click on graph for more.
ironport
websense
barracuda