US Cable Support > Comcast HSI > [Speed] Anyone having problems?

[Speed] Anyone having problems?

use a test server from your area.

reply to Warrior1986
Warrior, I'm in Park Ridge, also.

FWIW, I have the lower tier 4000/384 service and I'm doing fine. I just ran speed tests like yours:

reply to Warrior1986
What does this test say?

»miranda.ctd.anl.gov:7123/

reply to Warrior1986
Here are the results of that website Dadkins.

This was in the main window.

click START to re-test
Checking for Middleboxes . . . . . . . . . . . . . . . . . . Done
running 10s outbound test (client to server) . . . . . 363.58Kb/s
running 10s inbound test (server to client) . . . . . . 3.82Mb/s
Your PC is connected to a Cable/DSL modem

This was under statistics.

WEB100 Enabled Statistics:
Checking for Middleboxes . . . . . . . . . . . . . . . . . . Done
running 10s outbound test (client to server) . . . . . 363.58Kb/s
running 10s inbound test (server to client) . . . . . . 3.82Mb/s

------ Client System Details ------
OS data: Name = Windows XP, Architecture = x86, Version = 5.1
Java data: Vendor = Sun Microsystems Inc., Version = 1.5.0_09

------ Web100 Detailed Analysis ------
Cable modem/DSL/T1 link found.
Link set to Full Duplex mode
No network congestion discovered.
Good network cable(s) found
Normal duplex operation found.

Web100 reports the Round trip time = 114.64 msec; the Packet size = 1460 Bytes; and
There were 1 packets retransmitted, 42 duplicate acks received, and 43 SACK blocks received
The connection stalled 1 times due to packet loss
The connection was idle 0.34 seconds (3.40%) of the time
This connection is receiver limited 85.46% of the time.
This connection is network limited 14.51% of the time.

Web100 reports TCP negotiated the optional Performance Settings to:
RFC 2018 Selective Acknowledgment: ON
RFC 896 Nagle Algorithm: ON
RFC 3168 Explicit Congestion Notification: OFF
RFC 1323 Time Stamping: OFF
RFC 1323 Window Scaling: OFF
Packet size is preserved End-to-End
Server IP addresses are preserved End-to-End
Information: Network Address Translation (NAT) box is modifying the Client's IP address

Finally, this was under More Details.

WEB100 Kernel Variables:
Client: localhost/127.0.0.1
AckPktsIn: 1743
AckPktsOut: 0
BytesRetrans: 1460
CongAvoid: 0
CongestionOverCount: 0
CongestionSignals: 1
CountRTT: 1700
CurCwnd: 17520
CurMSS: 1460
CurRTO: 340
CurRwinRcvd: 65535
CurRwinSent: 5840
CurSsthresh: 32120
DSACKDups: 43
DataBytesIn: 0
DataBytesOut: 4877860
DataPktsIn: 0
DataPktsOut: 3341
DupAcksIn: 42
ECNEnabled: 0
FastRetran: 0
MaxCwnd: 65700
MaxMSS: 1460
MaxRTO: 350
MaxRTT: 220
MaxRwinRcvd: 65535
MaxRwinSent: 5840
MaxSsthresh: 32120
MinMSS: 1460
MinRTO: 320
MinRTT: 100
MinRwinRcvd: 65535
MinRwinSent: 5840
NagleEnabled: 1
OtherReductions: 0
PktsIn: 1743
PktsOut: 3341
PktsRetrans: 1
X_Rcvbuf: 107520
RcvWinScale: 2147483647
SACKEnabled: 3
SACKsRcvd: 43
SendStall: 0
SlowStart: 54
SampleRTT: 110
SmoothedRTT: 120
X_Sndbuf: 107520
SndWinScale: 2147483647
SndLimTimeRwin: 8618699
SndLimTimeCwnd: 1462945
SndLimTimeSender: 3264
SndLimTransRwin: 1
SndLimTransCwnd: 2
SndLimTransSender: 1
SndLimBytesRwin: 4647180
SndLimBytesCwnd: 230680
SndLimBytesSender: 0
SubsequentTimeouts: 0
SumRTT: 194880
Timeouts: 1
TimestampsEnabled: 0
WinScaleRcvd: 2147483647
WinScaleSent: 2147483647
DupAcksOut: 0
StartTimeUsec: 436490
Duration: 10086416
c2sData: 2
c2sAck: 2
s2cData: 3
s2cAck: 3
half_duplex: 0
link: 100
congestion: 0
bad_cable: 0
mismatch: 0
spd: 0.00
bw: 5.62
loss: 0.000299312
avgrtt: 114.64
waitsec: 0.34
timesec: 10.00
order: 0.0241
rwintime: 0.8546
sendtime: 0.0003
cwndtime: 0.1451
rwin: 0.5000
swin: 0.8203
cwin: 0.5013
rttsec: 0.114635
Sndbuf: 107520
aspd: 0.00000

Checking for mismatch on uplink
(speed > 50 [0>50], (xmitspeed .9) [0.85>.9], (loss .15) [2.99>.15], (cwndtime > .6) [0.14>.6],
(loss 0) [32120>0]
Checking for 10 Mbps link
(speed 3.0) [0>3.0]
(xmitspeed 0) [3.0>0]
Checking for Wireless link
(sendtime = 0) [3.0E=0], (speed 50 [5.62>50], (Rwintime > 90) [0.85>.90]
(RwinTrans/CwndTrans = 1) [1/2=1], (mylink > 0) [3.0>0]
Checking for DSL/Cable Modem link
(speed 0) [3.0>0]
Checking for half-duplex condition
(rwintime > .95) [0.85>.95], (RwinTrans/sec > 30) [0.1>30],
(SenderTrans/sec > 30) [0.1>30], OR (mylink .02) [0.14>.02], (mismatch = 0) [0=0]
(MaxSsthresh > 0) [32120>0]

estimate = 5.62 based on packet size = 11Kbits, RTT = 114.64msec, and loss = 2.99312E-4
The theoretical network limit is 5.62 Mbps
The NDT server has a 105.0 KByte buffer which limits the throughput to 7.15 Mbps
Your PC/Workstation has a 63.0 KByte buffer which limits the throughput to 4.36 Mbps
The network based flow control limits the throughput to 4.37 Mbps

Client Data reports link is 'T1', Client Acks report link is 'T1'
Server Data reports link is 'Ethernet', Server Acks report link is 'Ethernet'

I'm not sure what all that means, but the section that caught my eye was the following.

The theoretical network limit is 5.62 Mbps
The NDT server has a 105.0 KByte buffer which limits the throughput to 7.15 Mbps
Your PC/Workstation has a 63.0 KByte buffer which limits the throughput to 4.36 Mbps
The network based flow control limits the throughput to 4.37 Mbps

So what do I do? Looks like it's something on my end I assume?

ha warrior...enjoying your comcast while home? i know i am...25 mbps down, 720 up and rock solid pings..ill take it over insight

reply to Warrior1986
LOL.

Actually, I'm not sure. I guess I technically pick here for gaming because all my pings are so low here compared to back at school.

But for downloading or browsing, definitely pick school. For some reason, I've got some issues here according to the test I ran above.

reply to Warrior1986
Oh, also my connection was down around 6pm or so according to my line monitor. Here's what the modem has to say.

2006-11-17 18:18:10 critical SYNC Timing Synchronization failure - Loss of Sync
2006-11-17 18:18:10 information Sync recovery loop is locked
2006-11-17 18:18:06 critical SYNC Timing Synchronization failure - Loss of Sync
2006-11-17 18:18:06 critical SYNC Timing Synchronization failure - Failed to acquire FEC framing
2006-11-17 18:17:58 warning Cable Lost FEC lock
2006-11-17 18:17:11 critical SYNC Timing Synchronization failure - Failed to acquire FEC framing
2006-11-17 18:17:11 warning Cable Lost FEC lock
2006-11-17 18:17:04 critical SYNC Timing Synchronization failure - Failed to acquire FEC framing
2006-11-17 18:17:04 warning Cable Lost FEC lock
2006-11-17 18:15:48 notice CM RF interface LinkUp
2006-11-17 18:15:48 information Authorized
2006-11-17 18:15:47 notice Cable Modem Status set to Registration Complete
2006-11-17 18:15:47 information Received REG-RSP from CMTS
2006-11-17 18:15:47 information Sending Registration Request
2006-11-17 18:15:47 information Processing Configuration File
2006-11-17 18:15:40 information DHCP: IP complete
2006-11-17 18:15:39 debug DHCP_coldstart() successfully
2006-11-17 18:15:36 information Beginning ranging process. Initial Power=43.00 dBmV
2006-11-17 18:15:33 information Sync recovery loop is locked
2006-11-17 18:15:29 information Scan Downstream Frequency...

I should add. The modem is quite old. It's a Linksys BEFCMU10. I got it at least 5 years ago. Same with the router. Linksys BEFSR41. But I really hope it's got nothing to do with those things as I never noticed a problem before.

reply to Warrior1986
Does anyone know how I can fix this? Or do I have to call Comcast and have someone come out?

Speedtest I just did. Not looking good.

reply to Warrior1986
Well, I just called and apparently I'm getting some packet loss. I'm not sure how much that should affect the speeds but I guess the tech will look and see why is there packet loss.

Is there anything I can do on my end to address this issue?

The theoretical network limit is 5.62 Mbps
The NDT server has a 105.0 KByte buffer which limits the throughput to 7.15 Mbps
Your PC/Workstation has a 63.0 KByte buffer which limits the throughput to 4.36 Mbps
The network based flow control limits the throughput to 4.37 Mbps

Adjusting that buffer or something?

Anyone?

trace routes to sites and your signal level readings from the modem (see forum faq's).

reply to Warrior1986
Essentially, run pingplotter or a traceroute to a site or two, to start generating some logs/documentation of packet loss.

What is your downstream SNR? Check at »192.168.100.1 and post the whole signals page here.
--
"Some people never see the light till it shines thru bullet holes." -Bruce Cockburn

I'm testing Gmail's spam filters: Broadbandreports1@gmail.com
Spam: 12900+ messages currently using 406 MB.

Speed test just run


Info from my modem signal page

Downstream Channel
The data shown in the table below provides information about the signal coming from the
network to your cable modem.
Lock Status Locked Modulation QAM256
Channel ID 69 Symbol rate 5360537 sym/sec
Downstream Frequency 711000000 Hz Max Bit Rate 6600000 bps
Downstream Power 6.32 dBmV SNR 36 dB

Upstream Channel
The data shown in the table below provides information about the signal being transmitted to
the network from your cable modem.
Lock Status Locked Modulation 16 QAM
Channel ID 9 Symbol rate 2560 ksym/sec
Upstream Frequency 24000000 Hz Max Bit Rate 384000 bps
Upstream Power 40.00 dBmV

Well, your signals look acceptable, SNR and downstream are fine, as well as upstream power level.

Have you tested against any other sites? Say »ftp://ftp1.optonline.net/pub/test64 ?

reply to Warrior1986
Here are some trace routes

Tracing route to www.l.google.com [72.14.203.104]
over a maximum of 30 hops:

1 * * * Request timed out.
2 11 ms 18 ms * 68.86.118.13
3 14 ms * * 10g-9-1-ar02.elmhurst.il.chicago.comcast.net [68
.87.230.45]
4 10 ms 13 ms * 68.87.231.165
5 10 ms 11 ms 12 ms 68.87.231.250
6 10 ms 11 ms 11 ms 12.125.194.9
7 13 ms 12 ms 12 ms tbr1-p011901.cgcil.ip.att.net [12.123.4.226]
8 12 ms 11 ms 12 ms ggr3-ge00.cgcil.ip.att.net [12.123.4.241]
9 32 ms 32 ms 30 ms att-gw.chi.qwest.net [192.205.32.98]
10 32 ms 32 ms 31 ms cer-core-02.inet.qwest.net [205.171.139.61]
11 32 ms 31 ms 31 ms chx-edge-01.inet.qwest.net [205.171.139.166]
12 12 ms 12 ms 12 ms 63.144.64.134
13 11 ms 13 ms 14 ms 66.249.95.253
14 14 ms 14 ms 28 ms 72.14.238.89
15 16 ms 16 ms 15 ms 64.233.175.94
16 13 ms 14 ms 13 ms ro-in-f104.google.com [72.14.203.104]

Trace complete.

Tracing route to www.comcast.net [204.127.195.15]
over a maximum of 30 hops:

1 * * * Request timed out.
2 10 ms * * 68.86.118.13
3 * 9 ms * 10g-9-1-ar02.elmhurst.il.chicago.comcast.net [68
.87.230.45]
4 13 ms 9 ms * 68.87.231.165
5 11 ms 10 ms 11 ms 68.87.231.250
6 12 ms 11 ms 11 ms 12.116.7.17
7 55 ms 54 ms 52 ms 12.122.99.10
8 52 ms 52 ms 52 ms tbr1-cl1.sffca.ip.att.net [12.122.10.6]
9 51 ms 53 ms 52 ms gar4-p300.sffca.ip.att.net [12.123.13.174]
10 52 ms 52 ms 52 ms idf22-gsr12-1-pos-7-0.rwc1.attens.net [12.122.25
5.218]
11 62 ms 62 ms 64 ms 63.241.85.98
12 * * * Request timed out.
13 51 ms 51 ms 50 ms www.comcast.net [204.127.195.15]

Trace complete.

reply to Nerdtalker

FTP Site Test

Here is a line quality test I just ran.

»/linequality/nil/2134027

reply to Warrior1986
Anyone?

Have you tried testing your speeds without your router?