Port 1088 Traffic Question Possible DOS attack?

I've used ethereal to capture packets on my network. We have a partial T1, 512k but the ISP says that it's pegged and I'm not sure why. They think that it could be a DOS attack. Here are the first two packets that I see, which are about 95% of the packets that I see are exactly the same as this one. I'm new at the networking stuff so any help would be greatly appreciated.

No. Time Source Destination Protocol Info
1 0.000000 192.168.0.51 234.8.7.1 UDP Source port: 1088 Destination port: 1088

Frame 1 (106 bytes on wire, 106 bytes captured)
Ethernet II, Src: 192.168.0.51 (00:11:d8:47:db:1f), Dst: 01:00:5e:08:07:01 (01:00:5e:08:07:01)
Internet Protocol, Src: 192.168.0.51 (192.168.0.51), Dst: 234.8.7.1 (234.8.7.1)
User Datagram Protocol, Src Port: 1088 (1088 ), Dst Port: 1088 (1088 )
Data (64 bytes)

0000 4b 53 49 2d 30 35 38 34 38 41 45 45 32 45 33 2d KSI-05848AEE2E3-
0010 50 6f 72 74 3a 33 36 35 30 00 00 00 00 00 00 00 Port:3650.......
0020 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

No. Time Source Destination Protocol Info
2 0.500013 192.168.0.51 234.8.7.1 UDP Source port: 1088 Destination port: 1088

Frame 2 (106 bytes on wire, 106 bytes captured)
Ethernet II, Src: 192.168.0.51 (00:11:d8:47:db:1f), Dst: 01:00:5e:08:07:01 (01:00:5e:08:07:01)
Internet Protocol, Src: 192.168.0.51 (192.168.0.51), Dst: 234.8.7.1 (234.8.7.1)
User Datagram Protocol, Src Port: 1088 (1088 ), Dst Port: 1088 (1088 )
Data (64 bytes)

0000 4b 53 49 2d 30 35 38 34 38 41 45 45 32 45 33 2d KSI-05848AEE2E3-
0010 50 6f 72 74 3a 33 36 35 30 00 00 00 00 00 00 00 Port:3650.......
0020 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

No. Time Source Destination Protocol Info
3 1.000050 192.168.0.51 234.8.7.1 UDP Source port: 1088 Destination port: 1088