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 (63.135.128.x/24) can spoof 8191 neighboring addresses (within your /19 prefix)
Spoofed source address (anon)
Prefix Length
ASN of spoofed source address
Received
63.135.128.x/24
/31
3663
natblock
63.135.128.x/24
/30
3663
natblock
63.135.128.x/24
/29
3663
natblock
63.135.128.x/24
/28
3663
natblock
63.135.128.x/24
/27
3663
natblock
63.135.128.x/24
/26
3663
natblock
63.135.128.x/24
/25
3663
natblock
63.135.128.x/24
/24
3663
natblock
63.135.129.x/24
/23
3663
yes
63.135.130.x/24
/22
3663
yes
63.135.132.x/24
/21
3663
yes
63.135.136.x/24
/20
3663
yes
63.135.144.x/24
/19
3663
yes
63.135.160.x/24
/18
22626
natblock
63.135.192.x/24
/17
7385
natblock
63.135.0.x/24
/16
23184
natblock
63.134.128.x/24
/15
32709
natblock
63.133.128.x/24
/14
18990
natblock
63.131.128.x/24
/13
14492
natblock
63.143.128.x/24
/12
6128
natblock
63.151.128.x/24
/11
209
natblock
63.167.128.x/24
/10
1239
natblock
63.199.128.x/24
/9
7018
natblock
63.7.128.x/24
/8
701
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.