Pattern of tests from this IP block indicates a switch from allowing spoofing to blocking it.
rewritten
Spoofed packet was received, but the source address was changed en route.
blocked
Spoofed packet was not received, but unspoofed packet was.
unknown
Neither spoofed nor unspoofed packet was received.
IPv4 AS Route:
This test run probed the following paths in order to infer your
ability to send different spoofed source packets. Each node
in the graph corresponds to an autonomous system, i.e.
different Internet service providers. NOTE: This graph does NOT show if
an AS blocks spoofed packets, only the path taken by received spoofed
packets. The IP Path Details
are available for this run. If non-spoofed packets weren't received at
a destination, the traceroute to that destination is not included in this
graph and may even cause a totally empty graph.
IPv4 Adjacent Netblock Testing:
Your host (208.81.4.x/24) can spoof 0 neighboring addresses
Spoofed source address (anon)
Prefix Length
ASN of spoofed source address
Received
208.81.4.x/24
/31
18451
sendto
208.81.4.x/24
/30
18451
sendto
208.81.4.x/24
/29
18451
sendto
208.81.4.x/24
/28
18451
no
208.81.4.x/24
/27
18451
sendto
208.81.4.x/24
/26
18451
sendto
208.81.4.x/24
/25
18451
sendto
208.81.4.x/24
/24
18451
sendto
208.81.5.x/24
/23
18451
sendto
208.81.6.x/24
/22
18451
no
208.81.0.x/24
/21
18451
no
208.81.12.x/24
/20
17382
sendto
208.81.20.x/24
/19
10340
sendto
208.81.36.x/24
/18
33010
sendto
208.81.68.x/24
/17
14600
sendto
208.81.132.x/24
/16
UNROUTED
no
208.80.4.x/24
/15
47002
sendto
208.83.4.x/24
/14
395336
sendto
208.85.4.x/24
/13
40244
sendto
208.89.4.x/24
/12
17359
sendto
208.65.4.x/24
/11
25813
sendto
208.113.4.x/24
/10
21570
sendto
208.17.4.x/24
/9
1239
no
208.209.4.x/24
/8
701
sendto
Meaning of status in Received column:
no
Packets spoofed from adjacent netblock were not received, probably due to blocking
sendto
The spoofer client was unable to send spoofed headers due to an operating system restriction.
IPv4 Outbound Filtering Depth:
The tracefilter test found your host
unable to spoof routable, non-adjacent source addresses through
even the first IP hop.
Summary:
The results from all tests are aggregated to produce a summary
"State of IP Spoofing" report.