From: Mike N. 

On Thu, 10 Jul 2003 17:19:44 -0400, Mike '/m'  wrote:

>It's trying to come in om UDP port 53, so it's not NetBIOS.  The way I
>turn it off is to block incoming port 53 requests.  :-)

  Perhaps your ISP has delegated your IP as authoritative for reverse DNS -
either for the
entire  class C or via a fractional class C subdelegation technique.

  The following sequence shows windows reverting to Netbios on the host when
DNS reverse
IP fails (which of course has nothing to do with what you're seeing on 53.).


23:59:19.0603 eth2 snd:
ETH 00C0F0087CDE->0004A827EFD0 typ=IP IP  len=46 id=49AB ttl=7F prot=UDP
ckSum=4F67 192.168.0.20->204.70.127.127 UDP 1191->53 len=32
ckSum=9AA0
02 2F 01 00 00 01 00 00  00 00 00 00 02 39 37 02   ./...........97.
32 34 01 31 03 32 31 30  07 69 6E 2D 61 64 64 72   24.1.210.in-addr
04 61 72 70 61 00 00 0C  00 01                     .arpa.....

23:59:19.4529 eth2 rcv:
ETH 0004A827EFD0->00C0F0087CDE typ=IP IP  len=9C id=AB37 ttl=72 prot=UDP
ckSum=FA84 204.70.127.127->192.168.0.20 UDP 53->1191 len=88
ckSum=1437
02 2F 85 83 00 01 00 00  00 01 00 00 02 39 37 02   ./...........97.
32 34 01 31 03 32 31 30  07 69 6E 2D 61 64 64 72   24.1.210.in-addr
04 61 72 70 61 00 00 0C  00 01 02 32 34 01 31 03   .arpa......24.1.
32 31 30 07 69 6E 2D 61  64 64 72 04 61 72 70 61   210.in-addr.arpa
00 00 06 00 01 00 00 2A  30 00 35 02 6E 73 04 74   .......*0.5.ns.t
6E 65 74 02 63 6F 02 74  68 00 07 70 72 6F 62 6C   net.co.th..probl
65 6D 07 6C 6F 78 69 6E  66 6F C0 53 77 64 49 6C   em.loxinfo.SwdIl
00 00 A8 C0 00 00 0E 10  00 09 3A 80 00 01 51 80   ..........:...Q.

23:59:19.4808 eth2 snd:
ETH 00C0F0087CDE->0004A827EFD0 typ=IP IP  len=4E id=49AC ttl=7F prot=UDP
ckSum=46D4 192.168.0.20->210.1.24.97 UDP 1192->137 len=3A ckSum=5312
FE 9D 00 00 00 01 00 00  00 00 00 00 20 43 4B 41   ............ CKA
41 41 41 41 41 41 41 41  41 41 41 41 41 41 41 41   AAAAAAAAAAAAAAAA
41 41 41 41 41 41 41 41  41 41 41 41 41 00 00 21   AAAAAAAAAAAAA..!
00 01                                              ..

--- BBBS/NT v4.01 Flag-4