Spoofing and Internet Filtering

Hi all,

I'm working on a project designed to determine the extent of ingress and
egress filtering on the Internet. Specifically interested in the ability
to forge headers and source spoofed packets. The project relies on
clients running an active measurement program from as wide a distribution
of netblocks as possible. If you're curious about your connection,
your upstream or how prevalent filtering is on other's networks,
try out the source or one of the binaries from:

Many more details of the program, methodology and current results are
on the web site as well. Thanks!


For those that expressed interest, in the month since this original
email, I collected results from around 300 unique hosts on ~200
netblocks and ~100 ASes. Statistics on spoofing coverage, operating
system blockage of raw sockets, NAT rewriting of spoofed headers,
inconsistent filtering policies and more are summarized here:

Thanks to all for their help!