Hi there,
I have searched the web to find the answer to this question and all I have come up with no real cause or solution.
The setup:
Time Warner Cable Internet Dynamic IP
DIR-655 A3 Firmware 1.21
3 hard wired, fully updated, virus free, windows xp pro machines
The Issue:
When only one PC is running or actively being used there is no issue. However, when there is moderate internet usage on a second pc the internet connection will drop (the WAN light on the router stays on as does the ethernet light on the modem) and give this pair of log entries.
[INFO] Thu Jan 08 21:27:37 2009 WAN interface cable has been connected
[INFO] Thu Jan 08 21:27:35 2009 WAN interface cable has been disconnected
This message can be forced by running any internet based game on the first by and then opening playing a movie on netflix. It will happen every time there is significant internet traffic on multiple pcs.
What I have tried:
Replaced with old netgear router no problems with the connection dropping connection.
Turned off all non essential options in the 655 (i.e. QoS, UPnP, Multicasting, traffic shaping, etc)
Reverted to old firmware versions to test.
Any insight? Thanks in advance.
EDIT
The Cause?: Incompatibility between DIR-655 and the Motorola SB-4100 cable modem (or perhaps bad modem, but I could not replicate the issue with an old router).
The Solution: Replace with newer modem. I would suggest any DOCSIS 2.0 modem, I specifically used the Linksys CM100, but the D-Link DCM-202 seems like a good option as well.