working with nemesis

[Bhaarath Venkateswaran <bhaarath.venkateswaran () lucidsecurity com>]

hello everybody,
       i am pretty new working on the packet crafting tool  nemesis. 
though i have efficiently used hping before , i thought nemesis is far 
more interesting than hping and hence started to play around with it, 
but iam still not able to observe the injected packet on my target using 
tcpdump, when the packet injection is successfull.

i have no problem in understanding the options  for all  the protocols 
fields and i even simulate and get the output for
some of the options and results that i got used using the tool are

C:\tools\>nemesis.exe icmp -v -i 13 -S 10.125.125.125  -D 
10.110.110.110  -G 10.107.107.127 -qT

ICMP Packet Injection -=- The NEMESIS Project Version 1.4beta3 (Build 22)

             [IP] 10.125.125.125 > 10.110.110.110
          [IP ID] 65286
       [IP Proto] ICMP (1)
         [IP TTL] 255
         [IP TOS] 00
 [IP Frag offset] 0000
  [IP Frag flags]

      [ICMP Type] Timestamp Request
      [ICMP Code] Timestamp Request
        [ICMP ID] 27402
[ICMP Seq number] 4459

Wrote 40 byte ICMP packet.

ICMP Packet Injected

now , i have successfully used it to get results for tcp and udp , but  
when i try to see the packet injected using tcpdump on my target which i 
attacked iam not able to see anything reaching the target , but the 
results i get show  that the packet has been successfully injected.

Am i missing something here?  enlighten me guys.
how can i know for certain that the target is attacked without seeing 
the packet getting thru to the target.

i do have an checkpoint firewall infront of the target. i do not see the 
packet in the firewall logs also.

thanking you for the same
bhaarath.v

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