Source 126.0.0.1 UDP/137

[<jlepich () fidmail com>]

Can anyone tell me what is causing these entries to pop up in my firewall log?
On our network we use a 10.x.x.x IP scheme. There is no host with the address
of 126.0.0.1 on our network anywhere. I was able to capture this by sniffing
the traffic from source 126.0.0.1.
............ CKAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAA..!
 
I have learned that this is a legitimate NetBIOS query.
 
Here is an excerpt from my firewall log.
 
Deny udp src inside:126.0.0.1/137 dst outside:3.13.0.10/137        (General
Electric, NJ USA)
Deny udp src inside:126.0.0.1/137 dst outside:63.14.0.10/137      (UUNET, VA,
USA )
Deny udp src inside:126.0.0.1/137 dst outside:210.11.0.10/137    (Asia
Pacific Network Information Centre, AU)
 
By sniffing the traffic I was able to find get the source MAC address. The
MAC I got is that of our core router. I have not attempted to track the source
beyond that router yet. 
 
-Jesse
___________________________________________________________
Fidelity Communications Webmail - http://webmail.fidnet.com



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