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 (187.120.23.x/24) can spoof 1023 neighboring addresses (within your /22 prefix)
Spoofed source address (anon)
Prefix Length
ASN of spoofed source address
Received
187.120.23.x/24
/31
262788
yes
187.120.23.x/24
/30
262788
natblock
187.120.23.x/24
/29
262788
yes
187.120.23.x/24
/28
262788
yes
187.120.23.x/24
/27
262788
natblock
187.120.23.x/24
/26
262788
natblock
187.120.23.x/24
/25
262788
natblock
187.120.23.x/24
/24
262788
natblock
187.120.22.x/24
/23
262788
natblock
187.120.21.x/24
/22
262788
yes
187.120.19.x/24
/21
266181
natblock
187.120.31.x/24
/20
266181
natblock
187.120.7.x/24
/19
22381
natblock
187.120.55.x/24
/18
262716
natblock
187.120.87.x/24
/17
28202
natblock
187.120.151.x/24
/16
53126
natblock
187.121.23.x/24
/15
19182
natblock
187.122.23.x/24
/14
28573
natblock
187.124.23.x/24
/13
7738
natblock
187.112.23.x/24
/12
18881
natblock
187.104.23.x/24
/11
28573
natblock
187.88.23.x/24
/10
26599
natblock
187.56.23.x/24
/9
27699
natblock
187.248.23.x/24
/8
22566
natblock
Meaning of status in Received column:
yes
Packets spoofed from adjacent netblock were received (but that netblock is within the source AS)
natblock
Spoofed probe packets appear to be blocked by your local NAT or firewall rather than being rewritten with a public source address.
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.
