FragGuard and Virtual Re-Assembly
fragguard and virtual re-assembly is a feature that provides ip fragment protection. this feature performs full reassembly of all icmp error messages and virtual-reassembly of the remaining ip fragments that are routed through the pix firewall. virtual reassembly is currently enabled by default.this feature uses syslog to log any fragment overlapping and small fragment offset anomalies, especially those caused by a teardrop.c attack.