What is the reverse-path filter?

[fox12345]

/etc/sysctl.conf
##############################################################3
# Functions previously found in netbase
#


# Uncomment the next two lines to enable Spoof protection (reverse-path filter)
# Turn on Source Address Verification in all interfaces to
# prevent some spoofing attacks
#net.ipv4.conf.default.rp_filter=1
#net.ipv4.conf.all.rp_filter=1


This is in the backtrack "/etc/sysctl.conf" So why this option give to us?
what is the reverse-path filter?
Are you think This option is most important to hide my ID?


Help me...

[lucid]

Ask intelligent questions with better english and you might get better responses. Seriously, begging for help just makes people like me want to delete your posts.