port 3717/udp?

[Jacek Lipkowski <sq5bpf () acid ch pw edu pl>]

i'm getting alot (one every few seconds) of packets destined for
one of my machines hitting port 3717/udp.

does anyone have an idea what it is?

Dec 20 21:17:51 firewall kernel: ##0 INPUT: IN=eth0 OUT=
MAC=00:05:5d:2b:c8:ea:00:c0:7b:a3:0e:22:08:00 SRC=81.56.150.220
DST=somehost LEN=47 TOS=0x00 PREC=0x00 TTL=99 ID=54039 PROTO=UDP SPT=11807
DPT=3717 LEN=27
Dec 20 21:18:28 firewall kernel: ##0 INPUT: IN=eth0 OUT=
MAC=00:05:5d:2b:c8:ea:00:c0:7b:a3:0e:22:08:00 SRC=68.59.42.250
DST=somehost
LEN=47 TOS=0x00 PREC=0x00 TTL=110 ID=4842 PROTO=UDP SPT=3243 DPT=3717
LEN=27
Dec 20 21:19:04 firewall kernel: ##0 INPUT: IN=eth0 OUT=
MAC=00:05:5d:2b:c8:ea:00:c0:7b:a3:0e:22:08:00 SRC=80.35.35.28 DST=somehost
LEN=47 TOS=0x00 PREC=0x00 TTL=106 ID=16010 PROTO=UDP SPT=9142 DPT=3717
LEN=27
Dec 20 21:19:40 firewall kernel: ##0 INPUT: IN=eth0 OUT=
MAC=00:05:5d:2b:c8:ea:00:c0:7b:a3:0e:22:08:00 SRC=203.2.94.119
DST=somehost
LEN=47 TOS=0x00 PREC=0x00 TTL=98 ID=42501 PROTO=UDP SPT=10044 DPT=3717
LEN=27
Dec 20 21:20:17 firewall kernel: ##0 INPUT: IN=eth0 OUT=
MAC=00:05:5d:2b:c8:ea:00:c0:7b:a3:0e:22:08:00 SRC=172.176.124.18
DST=somehost LEN=47 TOS=0x00 PREC=0x00 TTL=113 ID=18305 PROTO=UDP SPT=8899
DPT=3717 LEN=27


sample packet:
21:04:11.001441 212.144.222.22.19673 > somehost.3717: [udp sum ok]
udp 19 (ttl 105, id 46615, len 47)
0x0000   4500 002f b617 0000 6911 d507 d490 de16        E../....i.......
0x0010   xxxx xxxx 4cd9 0e85 001b xxxx e30e 049f        xxxxL.....xx....
0x0020   c1d4 8a27 8233 fa0c 9899 3da0 74e5 0c          ...'.3....=.t..

jacek



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