Hi, I am a Rogers broadband customer. I have a Motorola modem, connected to a D-Link ethernet router.

Over the last week or so, I've noticed that there is continuous traffic between the modem and the router. The PC Activity light on the modem and the WAN light on the router both blink rapidly and incessently. This occurs whether or not I have any computers connected to the router. At first I thought it was some kind of incoming traffic/attack from the internet, but if I disconnect the router, the modem's Activity light ceases to blink; it will immediately resume blinking once the router is reconnected. This behaviour also persists when the modem is connected directly to a computer without the router.

In the time since I first noticed this traffic, I have upgraded my service from Rogers Lite to Express. The blinking continues, although it does not seem to affect my internet connection whatsoever: I get full bandwidth at either service level. There is nothing indicating any kind of problem in either the modem or the router's logs or status pages.

I'm inquiring about this because I've only noticed this activity recently, and I've had Rogers for some time. Since it does not seem to be interfering with anything, can it be safely ignored?

Thanks...

If you unplug the computer, does the traffic continue between the router and the modem? If not, I'd hazard a guess that you are running something on your PC that is doing a lot of web traffic.

Tom

Hi, thanks for your reply. The traffic between the router and the modem continues even if I physically disconnect both computers. The modem's "PC Activity" light only stops flashing if I disconnect the router; it starts again immediately after re-connecting, so it doesn't seem to be coming from the internet side.

I am willing to bet that your IP address recently changed.

Earlier this month my IP address changed and since then the DHCP server has been pounding the crap out of my modem/router. It has trailed off but is still happening 3 weeks later.

A moderator on dslreports thinks it is the DHCP server trying to provision the modems that get turned off during the IP address reclamation process.

Yes, I do seem to recall having an IP address in the 74. (?) range, and am now part of the infamous 99.x.x.x.

Would the traffic from the DHCP server stop as soon as the router or computer is disconnected from the modem, and then start again immediately upon reconnect? Because that's what I'm seeing here.

A new development is that the constant blinking now has an occasional, brief pause; unfortunately, my internet connection does too, although it is almost imperceptible most of the time. :/

I'm hoping this is just part of some transition and that it will work itself out eventually...

I am with Shaw Internet and using a Motorola cable modem , Model SB5101. I was offered this in replacement for my old modem that I had purchased a few years ago.

One thing I noticed about the new modem is that it has different status lights. The old one had a status light for Internet send and receive while the new one has just a PC activity light. From the very first I observed that the PC Activity status was almost always on but flickering. This was even if all my computers are shut off and there is no Wi-Fi activity. I even checked it with the Wi-Fi functionality turned off. Basically it is a useless status light as it is always in the same state. I just noticed this thread and thought I would add my experience and will follow this thread to see if I can learn anything new on the situation.

Just for your information, the new modem supports higher speeds and I was given a free trade and 1 month free trial of the next higher speed service. I said I didn't think the extra speed would be worth the extra $10 a month. The offer stood so I replaced my old modem and found that Internet access was faster but not enough to be worth the $10 a month extra so made sure I canceled before my free period was up.

Hi,

Interesting, OP, you are not alone.
Mine started doing the exact same thing just today. I did the same as you, I was able to determine it was the motorola modem talking, even with everything turned off.

I contacted Rogers and tried to get an answer of why this is happening. The technical rep said she didn't know why, but, some customers report having a constant blinking and some don't.

The why still goes unanswered but at least you know you aren't alone.

Edit:

Cable Modem's config/log pages http://192.168.100.1

The problem is on Rogers end I suspect perhaps a time sync issue (at least that's what I see in my log).

I am getting the EXACT same thing my friend.

Anyone get a response on what to do?

In searches of modem FAQs and other forums the most common answer to the question seems to be:

If your "PC Activity" light is blinking rapidly, then that's normal operation.

I know my Motorola modem, with a Linksys router on Rogers, is always flashing whether the computer is on or off. I have had constant speeds and uptime for months so I am reluctant to turn off either the modem or router to test any further. ;)

Thanks for the responses. I guess the flashing light is simply part of normal operation. It just struck me as odd that I've only noticed this behaviour in recent weeks, while I've had the service for well over a year.
However, I see that I'm not alone, and since it doesn't seem to reflect any sort of malicious traffic and it isn't affecting my bandwidth, I'm quite content to ignore it. Cheers!

Hello,

I took at look at my modem's log pages and there is a ton of error messages that have the incorrect time stamp and the error message contains,

Time Priority Code Description
1970-01-01 00:00:13 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:15 3-Critical D001.0 DHCP FAILED - Discover sent, no offer received
1970-01-01 00:00:10 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:25 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
1970-01-01 00:00:11 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
1970-01-01 00:00:11 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
1970-01-01 00:00:02 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
1970-01-01 00:00:13 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:28 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
1970-01-01 00:00:13 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
1970-01-01 00:00:13 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
1970-01-01 00:00:12 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:09 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:11 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
2007-08-20 18:53:10 3-Critical R005.0 Started Unicast Maintenance Ranging - No Response received - T3 time-out
1970-01-01 00:00:12 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:06 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:12 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:01:34 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
1970-01-01 00:01:19 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
1970-01-01 00:01:19 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
1970-01-01 00:00:56 3-Critical R004.0 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance o
1970-01-01 00:00:23 3-Critical R005.0 Started Unicast Maintenance Ranging - No Response received - T3 time-out
1970-01-01 00:00:07 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:10 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:07 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:12 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:09 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:14 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:09 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:12 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:08 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:11 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:09 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:16 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:09 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:13 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:08 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:13 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:09 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:14 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:09 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:12 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:07 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:11 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:09 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:14 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:07 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:00:12 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
2007-04-03 23:40:27 5-Warning D103.0 DHCP RENEW WARNING - Field invalid in response
2007-04-03 22:40:44 6-Notice I401.0 TLV-11 - unrecognized OID
1970-01-01 00:00:12 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
2007-04-03 22:35:11 6-Notice I401.0 TLV-11 - unrecognized OID
1970-01-01 00:01:30 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:01:27 3-Critical D001.0 DHCP FAILED - Discover sent, no offer received
1970-01-01 00:01:17 3-Critical R002.0 No Ranging Response received - T3 time-out
1970-01-01 00:01:01 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
1970-01-01 00:00:28 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
1970-01-01 00:00:28 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
1970-01-01 00:00:27 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
1970-01-01 00:00:27 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
1970-01-01 00:00:10 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
1970-01-01 00:00:10 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing

Can someone look at this information and help me? I'm on Rogers.

That's your problem right there: You're trying to access the internet from 1970 with a PET computer from Commodore!!! ;)

Seriously, why is your router show january 1st 1970?

Also, we need more info like router, modem used and so on.

Its the one we are talking about in this thread, the MOtorola Surfboard sb5101. I have rogers also, and my IP address had changed to the 99.xxx range.

My bad....I guess I let my fingers do the typing instead of my eyes reading the whole thread...:o
Have you tried unplugging your modem for 5 minutes and let it reset itself? My guess would be that it will ask for new DHCP and hopefully get the proper info minus all the errors you got. I know it's low key but you have to start somewhere.

It appears I am not alone afterall. I too have a Motorola SB5101 cable modem on a D-Link router on the Rogers network and just found out that I was moved from a 74.X network to a 99.X network and now my cable modem pc/activity light flashes constantly as well.

When my IP address was 74.X range, my pc/activity light never blinked if my home system was turned off, now without any computers being on, and with wireless disconnected, my pc/activity light flashed constantly. A definite change from before. I am not too sure whether my performance on the network is impacted and the speedtest site http://speedcheck.rogers.com/ doesn't indicate that performance is affected. Their tech support is useless as all they tell me is that my cable signal is strong, no explanation for the change in the pc/activity light. With all the IP port scans and hackers out there, I would hate to find out that I am a target for a hacker and Rogers is not willing to do anything about it.

I will keep trying to get an answer though!

Well I have been on 99.X IPs for quite some time and just recently all the activity lights stopped flashing. :confused:

My network performance does not seem to be impacted whether there are flashing activity lights or not...although they do look kind of cool in the dark. ;)