Basic Internet Connectivity And Modem Help

[ccomer]

For the past few days I've been having some intermittent issues in Houston, TX (Southwest side, in Katy) that have been causing some considerable headaches.

During the day my connection seems work fine. I have about 25mbps down and 3.5mbps up with really low latency and no packet loss what so ever during usual business hours. However in the evening starting right around 6-8pm something happens and I started to experience packet loss between 10-15% making the internet nearly unusable. Most websites take 20-30 seconds to even resolve and then loading the pages can take several minutes. I'm not able to keep a consistant connection to remote servers. Anything that depends on me uploading data somewhere fails completely (such as FTP or SCP).

A couple of things I've noticed. When this started happening, my IP changed and I started using a completely different gateway than I had been using the past ~2-3 years. I know this because I work form home and I've had the same IP for nearly the lifetime of my service with Comcast. I have iptables setup on a number of servers I work on and when this started happening, one of the first things I noticed was my inability to connect to those servers due to the change in IP address.

What's very very interesting to me is I noticed yesterday while the internet was working I was back on the old gateway and I was using my old IP address again. It makes me wonder if this is some kind of temporary gateway setup while they do some kind of maintenance of upgrade? Here's the information for my current connection.

Internet IP Address:      98.197.242.121
Subnet Mask:      255.255.254.0
Default Gateway:      98.197.242.1
DNS1:      75.75.76.76
DNS2:      75.75.75.75

Here's what a ping to google.com looks like for me.

64 bytes from 74.125.227.133: icmp_seq=5965 ttl=54 time=17.920 ms
64 bytes from 74.125.227.133: icmp_seq=5966 ttl=54 time=14.879 ms
64 bytes from 74.125.227.133: icmp_seq=5967 ttl=54 time=15.816 ms
Request timeout for icmp_seq 71504
Request timeout for icmp_seq 71505
64 bytes from 74.125.227.133: icmp_seq=5970 ttl=54 time=15.906 ms
Request timeout for icmp_seq 71507
64 bytes from 74.125.227.133: icmp_seq=5972 ttl=54 time=16.692 ms
Request timeout for icmp_seq 71509
64 bytes from 74.125.227.133: icmp_seq=5974 ttl=54 time=15.584 ms
64 bytes from 74.125.227.133: icmp_seq=5975 ttl=54 time=14.214 ms

Here's a traceroute to google.com

$ traceroute google.com
traceroute: Warning: google.com has multiple addresses; using 74.125.227.104
traceroute to google.com (74.125.227.104), 64 hops max, 52 byte packets
 1  192.168.1.1 (192.168.1.1)  1.464 ms  1.273 ms  1.309 ms
 2  73.211.110.1 (73.211.110.1)  7.755 ms  9.636 ms  7.899 ms
 3  ge-2-30-ur02.rosenberg.tx.houston.comcast.net (68.85.251.113)  8.963 ms  9.184 ms *
 4  * xe-11-0-0-0-sur01.rosenberg.tx.houston.comcast.net (68.85.246.165)  10.110 ms *
 5  xe-2-1-1-0-ar01.bearcreek.tx.houston.comcast.net (68.85.247.129)  9.838 ms  9.416 ms  10.066 ms
 6  pos-0-6-0-0-pe01.56marietta.ga.ibone.comcast.net (68.86.94.137)  18.235 ms
    pos-3-7-0-0-cr01.dallas.tx.ibone.comcast.net (68.86.90.29)  15.702 ms
    pos-0-5-0-0-pe01.56marietta.ga.ibone.comcast.net (68.86.94.141)  17.872 ms
 7  pos-0-2-0-0-pe01.1950stemmons.tx.ibone.comcast.net (68.86.86.150)  15.491 ms  15.389 ms  16.206 ms
 8  75.149.231.70 (75.149.231.70)  112.676 ms  86.486 ms  80.232 ms
 9  72.14.233.77 (72.14.233.77)  14.581 ms  15.364 ms *
10  209.85.240.91 (209.85.240.91)  14.735 ms  16.090 ms  15.892 ms
11  dfw06s16-in-f8.1e100.net (74.125.227.104)  15.128 ms  15.728 ms  16.468 ms

Notice I start seeing dropped packets immediately at the edge router here in Rosenburg, this has been pretty consistent.

Here's what Shaperprobe says:

DiffProbe release. January 2012.
Shaper Detection Module.

Connected to server 64.9.225.166.

Estimating capacity:
Upstream: 382 Kbps.
Downstream: 20480 Kbps.

The measurement will last for about 4.0 minutes. Please wait.

Checking for traffic shapers:

Upstream: Measurement aborted due to high packet loss rate.
logout

[Process completed]

Here's the status info from my modem:

RF Parameters Downstream
Frequency:    591.000 MHz
Power:    -3 dBmV
Signal to Noise Ratio:    38 dB
Modulation:    QAM-256

Upstream
Frequency:    31.800 MHz
Power:    50 dBmV
Upstream Data Rate:    5120 Ksymbol/second
Modulation:    QAM-64

Status
System uptime    0 days 00h:38m:42s
Computers Detected:    2
CM Status:    Operational
WAN Isolation:    OFF
Time and Date:    Sat Mar 24 20:33:17 2012

Interfaces Parameters(for each interface)
Interface Name    Provisioned    State    Speed    MAC Address
LAN: Ethernet Interface    Enabled    Up    100    00:11:e6:de:40:17
Cable: Cable Modem Interface CATV-MAC IF    Enabled    Up    0    00:11:e6:de:40:14
Cable: Cable Modem Interface CATV-DS IF    Enabled    Up    43    n/a
Cable: Cable Modem Interface CATV-US IF    Enabled    Up    31    n/a
USB: USB Interface    Enabled    Dormant    12    00:11:e6:de:40:15
Software Loopback    Enabled    Up    0    n/a
PacketCable Embedded Interface    Enabled    Up    0    00:11:e6:de:40:16

And the event log from my modem as well:

CM Event Log
Date/Time    Event Level    Event ID    Description
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/23/2012 21:30    Critical (3)    I2.0    REG RSP not received
03/23/2012 21:30    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/23/2012 21:29    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/23/2012 21:28    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/22/2012 20:01    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/22/2012 20:01    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
03/22/2012 20:01    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/22/2012 20:00    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/22/2012 19:16    Error (4)    C401.0    DCC-ACK not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/22/2012 01:10    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Warning (5)    D4.1    ToD request sent - No Response received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response

Pingtest.net

http://www.pingtest.net/result/59601362.png

Speedtest.net
I cannot complete a test here or using the Comcast speed test, they both say they're unable to upload anything.

What's weird about this is when it happens, my ping is still usually pretty good between 10-30ms for most servers, and my download speed is essentially cut in half coming in at 10-12mbps but I seem to have almost 0 upload speed.

It's uncanny that this has happened now for 5 days straight in a row with the same predictable behaviour and time... surely this has to be something like scheduled maintenance? I had a technician out to check the line a long while ago (over a year) and he said everything was fine at the time; do I need to have someone out again? I'm really frustrated since I work online from home and I have to have the internet but I can't seem to get this fixed and there's absolutely no other choice for high speed internet in my area.

I spoke to a neighbor and he was also having problems with his internet. Not exactly the same issue as me, but he has had bouts of downtime over the past few days between 10-30 minutes long. Could this be related?

Anyone have suggestions? Comcast, any way someone who actually knows what a traceroute is could see this and I won't have to explain what's going on to someone who's going to ask me to unplug my modem over and over again? It would be great if somehow a net admin could see this and just take a look; it just seems like there's something going on here that someone would have some information on. I don't mind waiting if I know this problem is going to be cleared up, but I can't keep operating like this. I would gladly pay to talk to a network admin who knew what he was doing, the phone support is severely lacking in understanding of anything beyond unplugging things.

[i-am-nerdburg]

Wow, thanks for all the info. Lets just start with the basics tho:

Please give us more information:

1) Please connect your computer directly to the modem via Ethernet ( no router, no wireless, no USB )
2) Run ShaperProbe and post your results. (It works with Win 7)
3) Post your upstream and downstream signal levels (click the link.) We are interested in your power levels (dBmV) and your Signal to Noise Ratio (SNR).
4) Let us know to what speed tier you subscribe.
5) Post the make a model of your modem.
6) Post your modem's error logs.

[UHFhd]

Found this post from UK discussion board . Seems like same issue but I'm a newbie .

  http://www.cableforum.co.uk/board/12/33660978-cable-slowed-crawl-peak-times-like.html

         Im sure someone will be along to escalate this issue to local folks .

 One other post that might be helpfull is router model . Besides one expert posted .

[ccomer]

1) The above information is consistant whether connecting to wifi, lan, or directly to the modem. I have a Cisco Linksys E4200 and I've tried using G, N and the gigbit lan to see if that made a difference, but I received the same packet loss and slow connections peeds no matter what method I was connecting.

One thing to note: every now and then when connecting to the modem, I would get a local dhcp IP instead of a real IP, usually 192.168.100.10 and I would have to restart the modem.

4) I believe I have Blast! - My billing simply states HIGH SPEED INTERNET but my usual download speeds seem consistent with what is offered as part of the Blast! plan. 

5) Looks like I have a Scientific Atlanta DPX2203 

6) The log is in the above post.

So it's the middle of the afternoon on Sunday and now the internet is working fine. No packet loss, speed is where it should be, although I am still using the new gateway and IP.

Speedtest.net

http://www.speedtest.net/result/1855510599.png

Pingtest.net

http://www.pingtest.net/result/59639010.png

Another thing to note, when logging into my account page, there is a notice that there's something going on in my area. This notice has been here for a whole week however. All I can do at this point is just cross my fingers and hope that Comcast gets things fixed soon. It's so frustrating having absolutely no control or not having any options in this situation especially when I work from home.

[i-am-nerdburg]

It sounds like they are doing upgrades in your area right now, so there is a possibility that you just need to ride things out for awhile. On the other hand, those Webstar modems are getting pretty long in the tooth and probably should be retired.

[ccomer]

Is there a particular modem that's recommend? This is the one Comcast provided when I started service with them ages ago, and I believe it was replaced once with the same model. Is it possible to request a different modem?

[ccomer]

Unfortunately it looks like I'm right back to massive slowness and packet loss.

 

Info from my modem:

 

RF Parameters Downstream
Frequency:     591.000 MHz
Power:    -3 dBmV
Signal to Noise Ratio:     39 dB
Modulation:    QAM-256

Upstream
Frequency:     31.800 MHz
Power:    53 dBmV
Upstream Data Rate:    5120 Ksymbol/second
Modulation:    QAM-64

Status
System uptime    0 days 06h:22m:24s
Computers Detected:    2
CM Status:    Operational
WAN Isolation:    OFF
Time and Date:    Sun Mar 25 20:57:41 2012

Interfaces Parameters(for each interface)
Interface Name    Provisioned    State    Speed    MAC Address
LAN: Ethernet Interface    Enabled    Up    100    00:11:e6:de:40:17
Cable: Cable Modem Interface CATV-MAC IF    Enabled    Up    0    00:11:e6:de:40:14
Cable: Cable Modem Interface CATV-DS IF    Enabled    Up    43    n/a
Cable: Cable Modem Interface CATV-US IF    Enabled    Up    31    n/a
USB: USB Interface    Enabled    Dormant    12    00:11:e6:de:40:15
Software Loopback    Enabled    Up    0    n/a
PacketCable Embedded Interface    Enabled    Up    0    00:11:e6:de:40:16

 

CM Event Log
Date/Time    Event Level    Event ID    Description
03/25/2012 19:07    Error (4)    C401.0    DCC-ACK not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/25/2012 14:35    Critical (3)         Resetting the cable modem due to docsDevResetNow
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/25/2012 14:34    Critical (3)         Resetting the cable modem due to docsDevResetNow
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/23/2012 21:30    Critical (3)    I2.0    REG RSP not received
03/23/2012 21:30    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/23/2012 21:29    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/23/2012 21:28    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/22/2012 20:01    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/22/2012 20:01    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
03/22/2012 20:01    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/22/2012 20:00    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/22/2012 19:16    Error (4)    C401.0    DCC-ACK not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/22/2012 01:10    Critical (3)    I2.0    REG RSP not received

 

Pingtest.net

http://www.pingtest.net/result/59662175.png

 

Can't run speedtest.net due to the packet loss.

[ccomer]

And now it seems to be back to working mostly...

If there is some sort of scheduled maintenance or something happeing during a particular time, it would be incredibly helpful to know this ... it's impossible to work during the time the connection is degraded, and if I could schedule my work around the time it will be available, that would be much better.

I wish there were options for high speed internet in my area.

[ccomer]

And again... starting at 8pm I am back to 11% packet loss and almost no upload speed. Cannot run a speedtest.net and shaperprobe won't run due to packet loss.

What is going on... why has this been happening for a week straight at this time, are they switching something off at a certain time???

I can't do anything with this!!

Comcast, anyone, please give me some information, when will this be fixed?????

[Pockaden]

You are describing exactly what I have been witnessing. Every time I call they say there is a reported signal degradation in the area. 3 times in the last 4 days... I Explained I usually get between 18-20 Mbps now I'm lucky if it works at all.

[EG]

Original poster. FWIW, the modem's upstream power level was only borderline in your first post and now in your latest post it is out of spec;  (Power: 53 dBmV). It should be in the range of 40 dB to 50 dB with 45 dB being the sweet spot and it shouldn't fluctuate more than 2-3 dB. This indicates an intermittent impairment in the return (upstream) path some where. It may be noise ingressing in to the lines somewhere between your modem and the neighborhood node device. Are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured ? This will help reduce the modem's need to shout so loud in order for the system to be able to hear it. If a premise tech can't find the source of the issue it is he who is responsible for escalating it to the line/maintenance techs to investigate the neighborhood plant/infrastructure.

In addition, it could be a problem with that modem. It is classifed as being "end of life" as of early 2009 on their Approved Modems List here; http://mydeviceinfo.comcast.net/  and should be swapped for a more  current model ASAP.

[bjackson57]

I have the same issue since Wednesday the 21st, and am just south of Katy in Richmond.

Every night right near 8pm I start receiving a lot of packet loss and timeouts.  Tried calling customer support 4 times, and they've set up tech appointments 3 times.  Every time I get a tech appointment scheduled, the next morning I get an automated call saying the issue is due to an area outage and service has been restored and they cancel the service call.  Yet my service will start having problems again at 8pm.  

[ccomer]

I'm going to be watching the connection tonight. It's just a little after 5:30pm and so far so good, today has been a normal day of activity and usage with expected speeds and performance.

Speedtest.net

http://www.speedtest.net/result/1859829969.png

Pingtest.net

http://www.pingtest.net/result/59779262.png

Modem status:

RF Parameters Downstream
Frequency:     591.000 MHz
Power:    -4 dBmV
Signal to Noise Ratio:     39 dB
Modulation:    QAM-256

Upstream
Frequency:     31.800 MHz
Power:    50 dBmV
Upstream Data Rate:    5120 Ksymbol/second
Modulation:    QAM-64

Status
System uptime    0 days 19h:57m:21s
Computers Detected:    2
CM Status:    Operational
WAN Isolation:    OFF
Time and Date:    Tue Mar 27 16:40:54 2012

Interfaces Parameters(for each interface)
Interface Name    Provisioned    State    Speed    MAC Address
LAN: Ethernet Interface    Enabled    Up    100    00:11:e6:de:40:17
Cable: Cable Modem Interface CATV-MAC IF    Enabled    Up    0    00:11:e6:de:40:14
Cable: Cable Modem Interface CATV-DS IF    Enabled    Up    43    n/a
Cable: Cable Modem Interface CATV-US IF    Enabled    Up    31    n/a
USB: USB Interface    Enabled    Dormant    12    00:11:e6:de:40:15
Software Loopback    Enabled    Up    0    n/a
PacketCable Embedded Interface    Enabled    Up    0    00:11:e6:de:40:16

Modem log:

CM Event Log
Date/Time    Event Level    Event ID    Description
03/27/2012 10:09    Critical (3)    T1.0    SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/25/2012 21:49    Error (4)    C401.0    DCC-ACK not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/25/2012 21:19    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
03/25/2012 21:18    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/25/2012 21:18    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/25/2012 21:17    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/25/2012 19:07    Error (4)    C401.0    DCC-ACK not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/25/2012 14:35    Critical (3)         Resetting the cable modem due to docsDevResetNow
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/25/2012 14:34    Critical (3)         Resetting the cable modem due to docsDevResetNow
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/23/2012 21:30    Critical (3)    I2.0    REG RSP not received
03/23/2012 21:30    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/23/2012 21:29    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/23/2012 21:28    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/22/2012 20:01    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/22/2012 20:01    Critical (3)    D2.0    DHCP FAILED - Request sent, No response

Shaperprobe:

DiffProbe release. January 2012.
Shaper Detection Module.

Connected to server 213.244.128.138.

Estimating capacity:
Upstream: 3587 Kbps.
Downstream: 106461 Kbps.

The measurement will last for about 3.0 minutes. Please wait.

Checking for traffic shapers:

Upstream: Burst size: 4903-4958 KB; Shaping rate: 2053 Kbps.

Downstream: Burst size: 5653-5745 KB; Shaping rate: 17584 Kbps.

For more information, visit: http://www.cc.gatech.edu/~partha/diffprobe
logout

[Process completed]

I noticed this while Shaperprobe was running, don't know if it is related...I've kept a terminal open pinging google.com for days now, just started this one up and noticed some random packet loss and spikes in latency.

64 bytes from 74.125.227.129: icmp_seq=472 ttl=54 time=18.340 ms
64 bytes from 74.125.227.129: icmp_seq=473 ttl=54 time=131.791 ms
64 bytes from 74.125.227.129: icmp_seq=474 ttl=54 time=313.576 ms
64 bytes from 74.125.227.129: icmp_seq=475 ttl=54 time=494.105 ms
64 bytes from 74.125.227.129: icmp_seq=476 ttl=54 time=682.578 ms
64 bytes from 74.125.227.129: icmp_seq=477 ttl=54 time=740.262 ms
64 bytes from 74.125.227.129: icmp_seq=478 ttl=54 time=16.629 ms
Request timeout for icmp_seq 479
Request timeout for icmp_seq 480
64 bytes from 74.125.227.129: icmp_seq=481 ttl=54 time=21.575 ms
64 bytes from 74.125.227.129: icmp_seq=482 ttl=54 time=21.573 ms
Request timeout for icmp_seq 483
Request timeout for icmp_seq 484
64 bytes from 74.125.227.129: icmp_seq=485 ttl=54 time=15.574 ms
Request timeout for icmp_seq 486
64 bytes from 74.125.227.129: icmp_seq=487 ttl=54 time=17.869 ms
64 bytes from 74.125.227.129: icmp_seq=488 ttl=54 time=18.931 ms

Let's see how tonight goes...

[ccomer]

EG: "In addition, it could be a problem with that modem. It is classifed as being "end of life" as of early 2009 on their Approved Modems List here; http://mydeviceinfo.comcast.net/  and should be swapped for a more  current model ASAP."

Thanks, I'm going to look into getting a replacement ASAP to help with order of elimination. I want to say the last time I had a technician out here to check on something unrelated he replaced the modem and it was after 2009 but I can't be sure.

As far as splitters go, the only thing I have is what the cable guy installed, so I believe I have the bare minimum. I'm convinced this is being caused by some sort of scheduled maintenance or some known process because it is becoming increasingly predictable for myself and other users in the area.

[ccomer]

As expected, after 8pm we're back to degraded service. 8% packet loss, can't run shaperprobe, can't run speedtest.net.

Pingtest.net

http://www.pingtest.net/result/59785347.png

Modem status:

RF Parameters Downstream
Frequency:     591.000 MHz
Power:    -4 dBmV
Signal to Noise Ratio:     39 dB
Modulation:    QAM-256

Upstream
Frequency:     31.800 MHz
Power:    50 dBmV
Upstream Data Rate:    5120 Ksymbol/second
Modulation:    QAM-64

Status
System uptime    0 days 22h:21m:03s
Computers Detected:    2
CM Status:    Operational
WAN Isolation:    OFF
Time and Date:    Tue Mar 27 19:04:36 2012

Interfaces Parameters(for each interface)
Interface Name    Provisioned    State    Speed    MAC Address
LAN: Ethernet Interface    Enabled    Up    100    00:11:e6:de:40:17
Cable: Cable Modem Interface CATV-MAC IF    Enabled    Up    0    00:11:e6:de:40:14
Cable: Cable Modem Interface CATV-DS IF    Enabled    Up    43    n/a
Cable: Cable Modem Interface CATV-US IF    Enabled    Up    31    n/a
USB: USB Interface    Enabled    Dormant    12    00:11:e6:de:40:15
Software Loopback    Enabled    Up    0    n/a
PacketCable Embedded Interface    Enabled    Up    0    00:11:e6:de:40:16

Model log:

CM Event Log
Date/Time    Event Level    Event ID    Description
03/27/2012 10:09    Critical (3)    T1.0    SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/25/2012 21:49    Error (4)    C401.0    DCC-ACK not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/25/2012 21:19    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
03/25/2012 21:18    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/25/2012 21:18    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/25/2012 21:17    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/25/2012 19:07    Error (4)    C401.0    DCC-ACK not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/25/2012 14:35    Critical (3)         Resetting the cable modem due to docsDevResetNow
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/25/2012 14:34    Critical (3)         Resetting the cable modem due to docsDevResetNow
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/23/2012 21:30    Critical (3)    I2.0    REG RSP not received
03/23/2012 21:30    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/23/2012 21:29    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/23/2012 21:28    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/22/2012 20:01    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/22/2012 20:01    Critical (3)    D2.0    DHCP FAILED - Request sent, No response

Tried unpluggin the modem and letting it sit for a while thinking maybe it needed a restart, but all of the information on the status screen stayed the same and these 3 new entries were in the event log

Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received

Pingtest.net after restarting the router (9% packet loss)

http://www.pingtest.net/result/59785881.png

I called Comcast again and after going through the unplugging jig we reset the modem and he watched as it cycle a few times trying to grab an IP and hung for a while. While we were talking it finally did get an IP but then dropped it again for a few minutes and then grabbed it again. I noticed some new entries in the event log of the modem.

Pingtest.net after the call (12% packet loss)

http://www.pingtest.net/result/59787194.png

Modem status: (after reset)

RF Parameters Downstream
Frequency:     609.000 MHz
Power:    -5 dBmV
Signal to Noise Ratio:     38 dB
Modulation:    QAM-256

Upstream
Frequency:     31.800 MHz
Power:    51 dBmV
Upstream Data Rate:    5120 Ksymbol/second
Modulation:    QAM-64

Status
System uptime    0 days 00h:11m:58s
Computers Detected:    2
CM Status:    Operational
WAN Isolation:    OFF
Time and Date:    Tue Mar 27 19:51:13 2012

Interfaces Parameters(for each interface)
Interface Name    Provisioned    State    Speed    MAC Address
LAN: Ethernet Interface    Enabled    Up    100    00:11:e6:de:40:17
Cable: Cable Modem Interface CATV-MAC IF    Enabled    Up    0    00:11:e6:de:40:14
Cable: Cable Modem Interface CATV-DS IF    Enabled    Up    43    n/a
Cable: Cable Modem Interface CATV-US IF    Enabled    Up    31    n/a
USB: USB Interface    Enabled    Dormant    12    00:11:e6:de:40:15
Software Loopback    Enabled    Up    0    n/a
PacketCable Embedded Interface    Enabled    Up    0    00:11:e6:de:40:16

Modem event log:

CM Event Log
Date/Time    Event Level    Event ID    Description
03/27/2012 19:43    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/27/2012 19:39    Notice (6)    E112.0    SW download Successful - Via Config file
03/27/2012 19:37    Notice (6)    E102.0    SW Download INIT - Via Config file ************************
03/27/2012 19:36    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/27/2012 19:36    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/27/2012 19:36    Critical (3)    R7.0    Unicast Ranging Received Abort Response - Re- initializing MAC
03/27/2012 19:36    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/27/2012 19:36    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/27/2012 19:35    Critical (3)    I2.0    REG RSP not received
03/27/2012 19:35    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/27/2012 19:35    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
03/27/2012 19:34    Critical (3)    R5.0    Started Unicast Maintenance Ranging - No Response received - T3
03/27/2012 19:34    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/27/2012 19:34    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/27/2012 19:33    Critical (3)    I2.0    REG RSP not received
03/27/2012 19:33    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/27/2012 19:33    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/27/2012 19:32    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
Time Not Established    Critical (3)    R5.0    Started Unicast Maintenance Ranging - No Response received - T3
Time Not Established    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/27/2012 19:36    Critical (3)    T1.0    SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK

The phone support guy said he wasn't able to see any known problems in the area, and we rescheduled a technician to come out to the house and check everything again. I guess I'm just going to update this thread every day with my before and after until Comcast can give me some kind of solution or until this goes away.

[Pockaden]

And.. it's back to screaming fast during the day.  Last night it was completely unresponsive.

[ccomer]

Pockaden: Yup, pretty much. What's really annoying is this is causing the tech appointments to be cancelled every morning, third time this morning.

Pingtest.net

http://www.pingtest.net/result/59817934.png

Speedtest.net

http://www.speedtest.net/result/1861131637.png

ShaperProbe

DiffProbe release. January 2012.
Shaper Detection Module.

Connected to server 80.239.142.202.

Estimating capacity:
Upstream: 3676 Kbps.
Downstream: 126503 Kbps.

The measurement will last for about 3.0 minutes. Please wait.

Checking for traffic shapers:

Upstream: Burst size: 4976-5028 KB; Shaping rate: 2090 Kbps.

Downstream: Burst size: 6217-6294 KB; Shaping rate: 17397 Kbps.

For more information, visit: http://www.cc.gatech.edu/~partha/diffprobe
logout

[Process completed]

Modem info:

RF Parameters Downstream
Frequency:     609.000 MHz
Power:    -6 dBmV
Signal to Noise Ratio:     38 dB
Modulation:    QAM-256

Upstream
Frequency:     25.000 MHz
Power:    49 dBmV
Upstream Data Rate:    2560 Ksymbol/second
Modulation:    QAM-64

Status
System uptime    0 days 14h:06m:58s
Computers Detected:    2
CM Status:    Operational
WAN Isolation:    OFF
Time and Date:    Wed Mar 28 09:46:16 2012

Interfaces Parameters(for each interface)
Interface Name    Provisioned    State    Speed    MAC Address
LAN: Ethernet Interface    Enabled    Up    100    00:11:e6:de:40:17
Cable: Cable Modem Interface CATV-MAC IF    Enabled    Up    0    00:11:e6:de:40:14
Cable: Cable Modem Interface CATV-DS IF    Enabled    Up    43    n/a
Cable: Cable Modem Interface CATV-US IF    Enabled    Up    15    n/a
USB: USB Interface    Enabled    Dormant    12    00:11:e6:de:40:15
Software Loopback    Enabled    Up    0    n/a
PacketCable Embedded Interface    Enabled    Up    0    00:11:e6:de:40:16

Modem log:

CM Event Log
Date/Time    Event Level    Event ID    Description
03/28/2012 08:09    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/28/2012 08:09    Critical (3)    R5.0    Started Unicast Maintenance Ranging - No Response received - T3
03/28/2012 08:09    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/28/2012 08:09    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/28/2012 08:08    Critical (3)    R5.0    Started Unicast Maintenance Ranging - No Response received - T3
03/28/2012 08:08    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/28/2012 08:07    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/28/2012 08:07    Critical (3)    R5.0    Started Unicast Maintenance Ranging - No Response received - T3
03/28/2012 07:54    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/28/2012 07:54    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/28/2012 07:53    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/28/2012 07:53    Critical (3)    R5.0    Started Unicast Maintenance Ranging - No Response received - T3
03/28/2012 07:52    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/28/2012 07:52    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/28/2012 07:51    Critical (3)    R5.0    Started Unicast Maintenance Ranging - No Response received - T3
03/27/2012 19:43    Critical (3)    I2.0    REG RSP not received
Time Not Established    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
Time Not Established    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
Time Not Established    Critical (3)    D1.0    DHCP FAILED - Discover sent, no offer received
03/27/2012 19:39    Notice (6)    E112.0    SW download Successful - Via Config file
03/27/2012 19:37    Notice (6)    E102.0    SW Download INIT - Via Config file ************************
03/27/2012 19:36    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/27/2012 19:36    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/27/2012 19:36    Critical (3)    R7.0    Unicast Ranging Received Abort Response - Re- initializing MAC
03/27/2012 19:36    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/27/2012 19:36    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica
03/27/2012 19:35    Critical (3)    I2.0    REG RSP not received
03/27/2012 19:35    Critical (3)    D3.0    DHCP FAILED - Requested Info not supported.
03/27/2012 19:35    Critical (3)    D2.0    DHCP FAILED - Request sent, No response
03/27/2012 19:34    Critical (3)    R5.0    Started Unicast Maintenance Ranging - No Response received - T3
03/27/2012 19:34    Critical (3)    R2.0    No Ranging Response received - T3 time-out
03/27/2012 19:34    Critical (3)    R4.0    Received Response to Broadcast Maintenance Request, But no Unica

Technician appointment for Thursday automatically cancelled this morning. Gotta call and try to have the appointment rescheduled... again...

[Pockaden]

Where are you pulling al those reports from?  I would like to help 

[ccomer]

Pockaden:

Posts by i-am-nerdburg and EG are extremely helpful, keep an eye out for them. i-am-nerdburg has one in this thread with some of the info you can help with, and EG provided a link earlier concerning the modems and which ones should be used for Comcast (to indicate that mine has been EOL since '09)

Please give us more information:

1) Please connect your computer directly to the modem via Ethernet ( no router, no wireless, no USB )
2) Run ShaperProbe and post your results. (It works with Win 7)
3) Post your upstream and downstream signal levels (click the link.) We are interested in your power levels (dBmV) and your Signal to Noise Ratio (SNR).
4) Let us know to what speed tier you subscribe.
5) Post the make a model of your modem.
6) Post your modem's error logs.

I use http://www.pingtest.net and http://www.speedtest.net to test the line and ShaperProbe (http://www.cc.gatech.edu/~partha/diffprobe/shaperprobe.html)

You can get your modem information going to http://192.168.100.1

[Pockaden]

And it's back to slow again

[bjackson57]

Yet again packet loss problems start at 8pm last night.  Fine in the morning of course.

My Arris TM502G modem (replacement from Comast 3/22) currently if it matters:

Downstream  

Freq/Power: 597.000 MHz -5 dBmV    

Signal to Noise Ratio:  37 dB    

Modulation: QAM256  

---

Upstream  

Freq/Power: 31.800 MHz 50 dBmV    

Channel Type: DOCSIS 2.0 (ATDMA)    

Symbol Rate: 5120 kSym/sec    

Modulation: QAM64

System Uptime: 3 days 11h:1m:1s

Computers Detected: 1

CM Status: Docsis-AC Power Iso OFF Data Reg Complete

Time and Date: THU MAR 29 07:07:07 2012

Interface Name Provisioned State Speed MAC address

LAN Enabled UP 100 (Full) 00-15-A3-C3-A7-9C

CABLE Enabled UP ---- 00-15-A3-C3-A7-9D

USB Enabled DOWN 12 00-15-A3-C3-A7-9F

MTA failConfigFileError DOWN ---- 00-15-A3-C3-A7-9E

[UHFhd]

 That's still a docsis 2 modem you may want to ask to have it swapped out for a docsis 3

                         http://mydeviceinfo.comcast.net/       considering your current speed tier 

[Pockaden]

We can post information all day long.. the fact of the matter is service is fine until about 8 o'clock P.M. then gets back to normal in the A.M.  this needs to be fixed or comcast is going to start hemmoraging customers.  If AT&T was available in my neighborhood I would have switched already.

[smithj1]

I have been experiencing the same issue the last few days only thing is I am in Michigan.  Roughly around 8 or 9 PM Eastern internet speeds drop to a screeching halt.  I called comcast a few nights ago about it and they said there was trouble in my area so i didnt worry about it and just went to bed early.  

Last night same thing happened called comcast they reset the modem had me try to run speedtest which was running horribly and had me reboot my computer several times.  Eventually it reported that I was getting a peak of about 3 meg down and couldnt give me a measurement for upstream.  Tech on the phone says he will send out a tech and the earliest he can get it scheduled is Friday at 4 PM.  So I grumble and take the appointment.  

After I got off the phone I decided to try and flush the dns cache and rebooted my system.  Went to speedtest again and reported 34 down and 7 meg up which is about the normal for me.  Just flushed the cache on my other computer and didnt reboot and was able to get about the same results from speedtest.  That worked for about an hour then things went back to a screeching halt.  So I opened a command prompt and flushed the dns again and it fixed the speeds again.  So my guess is maybe comcast is having some sort of DNS issue maybe?  Debating on keeping the appointment or not since the issue only appears in the evening.

[UHFhd]

smithj1         What type modem and router ?      

[Pockaden]

I have a technician coming out to my home today.  I will be leaving work in a few minutes and headed home to gather every single piece of information anyone wants.

[smithj1]

@ UHFhd

Not at home right now I believe its an Aris brand modem.  Its the one that does phone and internet.  I do have a Trendnet brand 4 port gigabit router with wireless N can't remember the exact model number right now sorry.  Connection has been solid until just recently.  Before calling last night I removed the router from the equation just to make sure it wasn't something on my end.

[Pockaden]

Well Nevermind they couldn't get me an appointment for today I scheduled for tomorrow morning.

[smithj1]

OK still at work but found out the model is the Aris TM602g/ct.  I forgot to mention during these periods of extreme slowness digital phone service does not seem to be affected all.

[Pockaden]

I am running tests while my service is working and will posts results now and when it stops in a couple hours (if I can that is).

[Pockaden]

1) Please connect your computer directly to the modem via Ethernet ( no router, no wireless, no USB )
2) Run ShaperProbe and post your results. (It works with Win 7)
3) Post your upstream and downstream signal levels (click the link.) We are interested in your power levels (dBmV) and your Signal to Noise Ratio (SNR).
4) Let us know to what speed tier you subscribe.
5) Post the make a model of your modem.
6) Post your modem's error logs.

I dont know how to post my modem information.. error logs etc..

I use http://www.pingtest.net and http://www.speedtest.net to test the line and ShaperProbe (http://www.cc.gatech.edu/~partha/diffprobe/shaperprobe.html)

You can get your modem information going to http://192.168.100.1

My first speedtest from http://www.speedtest.net was as follows - http://www.speedtest.net/result/1863960142.png  this was taken at 6:21 P.M. 3/29/2012

Pingtest.net gathered the following information at 6:24 P.M. –

http://www.pingtest.net/result/59909234.png

Modem info -

Cable Modem : DOCSIS 1.0/1.1/2.0 Compliant

MAC Address : C4:46:19:0D0:3C

IP Address : 73.211.111.240

IPV6 Address : ::

Serial Number : 0652F11003250

Boot Code Version : 1.1.2b

Software Version : 2.105.3002

Hardware Version : 1.3

CA Key : Installed

I have the blast residential service.

Here are my shaperprobe results: DiffProbe release. January 2012. Build 1008.

Shaper Detection Module.

Connected to server 217.163.1.100.

Estimating capacity:

Upstream: 3211 Kbps.

Downstream: 31367 Kbps.

The measurement will take upto 2.5 minutes. Please wait.

Checking for traffic shapers:

Upstream: No shaper detected.

Median received rate: 3136 Kbps.

Downstream: Burst size: 29107-29373 KB;

Shaping rate: 24434 Kbps.

For more information, visit: http://www.cc.gatech.edu/~partha/diffprobe

[Pockaden]

9:30 and it's working for now.  I had to reboot my modem twice. 

[smithj1]

I didn't seem to have any connection issues last night either.  Maybe Comcast finally figured out what was broken?

[bjackson57]

There was two trucks out in my neighborhood last night watching signals waiting for 8pm to hit. Tried later that night and been good since, knock on wood.

[Pockaden]

Mine is working tonight as well.  

[rdoussa]

I'm in the Houston area, as well and have been having problems for almost two weeks now. Like the above posters, it is mostly unuseable at night and, unfortuantely, I work from home at night (or at least I try to, but can't with this packet loss).

I did have a tech out the other day and he said everything was fine at my home, but that a "plant is out" in my area and they're working to get it fixed. I'm not a tech person, so I have no idea what that even means or if it makes sense for something like that to take 2+ weeks to fix.

I call in every day and every day I'm told the issue is being worked on and has a estimated fix time of 1 to four hours. It's never fixed, though. I plan on calling to get credited for all of the down time, but it doesn't make the loss of time/income any easier to deal with.

Does anyone have any info on a "plant outage" and what kind of down time might be reasonable?