Lots of dropped 10.132.88.1:67 packets from WAN port

Hi,

I see a pair of these broadcast(?) packets every 25-35 seconds whenever I enable logging on this FW rule:

3    ;;; defconf: drop all from WAN
      chain=input action=drop tcp-flags="" in-interface=ether1 log=no log-prefix="WANDrop "



16:46:36 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 394 
16:46:36 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 394 
16:48:53 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 344 
16:49:14 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 394 
16:49:14 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 394 
16:50:49 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 394 
16:50:49 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 394 
16:52:41 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 344 
16:53:04 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 344 
16:53:04 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 344 
16:53:30 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 344 
16:53:30 firewall,info WANDrop  input: in:ether1 out:(none), src-mac 60:73:5c:72:23:d9, proto UDP, 10.132.88.1:67->255.255.255.255:68, len 344

Is my ISP checking to see if I’m alive?