D-Link Time Server Abuse Running Rampant
The combination of a poor implementation of the protocol, and the fact that millions of people are probably using these routers are simply swamping the time servers that were providing these services and actually costing them so much money on bandwidth charges that many have been turned off. The shame is most people don't know they are causing this problem!
Normally you would ask permission of these various entities if you would like to use stratum 1 or 2 (first tier, second) time sourcing which is generally only available for one server in an office (other servers are expected to ask this one). If you had a whole office load of servers and PCs your would only connect to the time server 1) with permission 2) with one machine. Imagine all the D-Link routers on home connections and you get an idea of how big this problem really is. The NTP protocol is very chatty, and that is why we would typically ask for permission!
As a part of being Net-Friendly I believe it is your duty to turn off the NTP setting on your router and set your clock to your computers clock! Look at my screen shot and the crude notations for which I apologize ahead of time. You can only do so much with MS Paint! Not only will you be saving bandwidth, and being nice to the net but you will be saving your tax dollars as most of the time sources are governmental or educational facilities!
Obligatory links to the Register story here.