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 (87.120.11.x/24) can spoof 0 neighboring addresses
Spoofed source address (anon)
Prefix Length
ASN of spoofed source address
Received
87.120.11.x/24
/31
51925
natblock
87.120.11.x/24
/30
51925
rewritten
87.120.11.x/24
/29
51925
natblock
87.120.11.x/24
/28
51925
natblock
87.120.11.x/24
/27
51925
natblock
87.120.11.x/24
/26
51925
natblock
87.120.11.x/24
/25
51925
natblock
87.120.11.x/24
/24
51925
natblock
87.120.10.x/24
/23
33802
natblock
87.120.9.x/24
/22
47748
natblock
87.120.15.x/24
/21
34577
natblock
87.120.3.x/24
/20
34577
natblock
87.120.27.x/24
/19
58271
natblock
87.120.43.x/24
/18
34224
natblock
87.120.75.x/24
/17
43561
natblock
87.120.139.x/24
/16
39396
natblock
87.121.11.x/24
/15
29030
natblock
87.122.11.x/24
/14
8881
natblock
87.124.11.x/24
/13
35456
natblock
87.112.11.x/24
/12
6871
natblock
87.104.11.x/24
/11
44869
natblock
87.88.11.x/24
/10
5410
natblock
87.56.11.x/24
/9
3292
natblock
87.248.11.x/24
/8
29492
natblock
Meaning of status in Received column:
natblock
Spoofed probe packets appear to be blocked by your local NAT or firewall rather than being rewritten with a public source address.
rewritten
The source address of the probe packets we received differs from the spoofed address. It appears that an intermediate device is rewriting your packet headers.
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.