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 (91.197.135.x/24) can spoof 0 neighboring addresses
Spoofed source address (anon)
Prefix Length
ASN of spoofed source address
Received
91.197.135.x/24
/31
204144
natblock
91.197.135.x/24
/30
204144
natblock
91.197.135.x/24
/29
204144
natblock
91.197.135.x/24
/28
204144
natblock
91.197.135.x/24
/27
204144
natblock
91.197.135.x/24
/26
204144
natblock
91.197.135.x/24
/25
204144
natblock
91.197.135.x/24
/24
204144
natblock
91.197.134.x/24
/23
204144
natblock
91.197.133.x/24
/22
204144
natblock
91.197.131.x/24
/21
8870
natblock
91.197.143.x/24
/20
43584
natblock
91.197.151.x/24
/19
30975
natblock
91.197.167.x/24
/18
43646
natblock
91.197.199.x/24
/17
210218
natblock
91.197.7.x/24
/16
43310
natblock
91.196.135.x/24
/15
43133
natblock
91.199.135.x/24
/14
UNROUTED
natblock
91.193.135.x/24
/13
5610
natblock
91.205.135.x/24
/12
48008
natblock
91.213.135.x/24
/11
42405
natblock
91.229.135.x/24
/10
UNROUTED
natblock
91.133.135.x/24
/9
197207
natblock
91.69.135.x/24
/8
15557
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.
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.