Just received an ASA with a SSM-20 module. I am trying to determine the most recent sensor software revision for the IPS module. v5.1(7)E1 has an Oct 18, 2007 issue date and version 6.0(3)E1 has a June 28, 2007 date. Which is the most current version?
6.x is the most recent version. What you're talking about are simply patch levels. It's certainly possible that the 5.x and 6.x versions are both being actively maintained (I haven't been paying much attention to 5.x since moving to 6.x). The "most recent" release or patch is relative to the version of software you're running. IOW, if 5.1(8)E1 is released tomorrow, 6.0(3)E1 is still the most current patch for customers running 6.x.