Does connection need tuning?

[lem53]

I just installed a new Motorola SB5120. My speed that I am paying for from Charter is supposed to be 3 meg download and 284 upload.

I did a tracert to yahoo.com:

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\tracert www.yahoo.com

Tracing route to www.yahoo-ht2.akadns.net [69.147.114.210]
over a maximum of 30 hops:

1 7 ms 6 ms 11 ms 10.175.32.1
2 24 ms 18 ms 17 ms 24-159-64-161.static.jcsn.tn.charter.com [24.159
.64.161]
3 17 ms 17 ms 18 ms 24-159-64-129.static.jcsn.tn.charter.com [24.159
.64.129]
4 17 ms 17 ms 17 ms 24-159-64-57.static.jcsn.tn.charter.com [24.159.
64.57]
5 19 ms 18 ms 17 ms 24-159-64-38.static.jcsn.tn.charter.com [24.159.
64.38]
6 31 ms 30 ms 31 ms kcm-edge-02.inet.qwest.net [65.120.164.81]
7 31 ms 31 ms 31 ms kcm-core-02.inet.qwest.net [205.171.29.30]
8 43 ms 43 ms 43 ms cer-core-01.inet.qwest.net [67.14.8.10]
9 45 ms 49 ms 43 ms chp-brdr-02.inet.qwest.net [205.171.139.114]
10 64 ms 65 ms 64 ms 63.146.26.62
11 63 ms 63 ms 65 ms if-1-0.core2.CT8-Chicago.teleglobe.net [66.110.1
4.177]
12 63 ms 64 ms 66 ms if-0-1-0.core2.NTO-NewYork.teleglobe.net [66.110
.14.22]
13 69 ms 70 ms 70 ms if-1-0-0.core3.AEQ-Ashburn.teleglobe.net [216.6.
51.5]
14 70 ms 70 ms 70 ms ix-3-1-8.core3.AEQ-Ashburn.teleglobe.net [216.6.
51.26]
15 70 ms 70 ms 71 ms ge-3-1-0-p140.msr1.re1.yahoo.com [216.115.108.57
]
16 70 ms 70 ms 70 ms ge-1-30.bas-a2.re3.yahoo.com [66.196.112.37]
17 70 ms 70 ms 69 ms f1.www.vip.re3.yahoo.com [69.147.114.210]

Trace complete.

[trogers]

The uneven ping times at hop 1 (which is your modem) suggest the following possible causes:

electrical interference from some nearby electrical device.

outdated firmware

loose cable connection or wiring.

[lem53]

I ran that Argonne network tool and here are the results. BTW, my modem is new and it is under the desk and isn't close to any electrical devices, its more than 18 inches. There are no loose cables or anything.

------ Web100 Detailed Analysis ------
Cable modem/DSL/T1 link found.
Link set to Full Duplex mode
Information: throughput is limited by other network traffic.
Good network cable(s) found
Normal duplex operation found.

Web100 reports the Round trip time = 181.28 msec; the Packet size = 1460 Bytes; and
There were 30 packets retransmitted, 56 duplicate acks received, and 84 SACK blocks received
The connection was idle 0 seconds (0%) of the time
This connection is network limited 99.97% 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: ON
Packet size is preserved End-to-End
Server IP addresses are preserved End-to-End
Client IP addresses are preserved End-to-End



Checking for mismatch on uplink
(speed > 50 [0>50], (xmitspeed < 5) [0.25<5]
(rwintime > .9) [0>.9], (loss < .01) [6.88<.01]
Checking for excessive errors condition
(loss/sec > .15) [6.88>.15], (cwndtime > .6) [0.99>.6],
(loss < .01) [6.88<.01], (MaxSsthresh > 0) [62780>0]
Checking for 10 Mbps link
(speed < 9.5) [0<9.5], (speed > 3.0) [0>3.0]
(xmitspeed < 9.5) [0.25<9.5] (loss < .01) [6.88<.01], (mylink > 0) [3.0>0]
Checking for Wireless link
(sendtime = 0) [3.0E=0], (speed < 5) [0<5]
(Estimate > 50 [2.34>50], (Rwintime > 90) [0>.90]
(RwinTrans/CwndTrans = 1) [0/1=1], (mylink > 0) [3.0>0]
Checking for DSL/Cable Modem link
(speed < 2) [0<2], (SndLimTransSender = 0) [1=0]
(SendTime = 0) [3.0E-4=0], (mylink > 0) [3.0>0]
Checking for half-duplex condition
(rwintime > .95) [0>.95], (RwinTrans/sec > 30) [0>30],
(SenderTrans/sec > 30) [0.1>30], OR (mylink <= 10) [3.0<=10]
Checking for congestion
(cwndtime > .02) [0.99>.02], (mismatch = 0) [0=0]
(MaxSsthresh > 0) [62780>0]

estimate = 2.34 based on packet size = 11Kbits, RTT = 181.28msec, and loss = 6.88231E-4
The theoretical network limit is 2.34 Mbps
The NDT server has a 8192.0 KByte buffer which limits the throughput to 353.05 Mbps
Your PC/Workstation has a 501.0 KByte buffer which limits the throughput to 21.62 Mbps
The network based flow control limits the throughput to 5.28 Mbps

Client Data reports link is 'T1', Client Acks report link is 'T1'
Server Data reports link is '10 Gig', Server Acks report link is 'Ethernet'



Results of the TCP optimizer

MTU = 1500
MTU is fully optimized for broadband.

MSS = 1460
Maximum useful data in each packet = 1460, which equals MSS.

Default TCP Receive Window (RWIN) = 513920
RWIN Scaling (RFC1323) = 3 bits (scale factor of 6)
Unscaled TCP Receive Window = 64240

RWIN is a multiple of MSS
Other RWIN values that might work well with your current MTU/MSS:
513920 (MSS x 44 * scale factor of 8) <-- current value
256960 (MSS x 44 * scale factor of 4)
128480 (MSS x 44 * scale factor of 2)
64240 (MSS x 44)

bandwidth * delay product (Note this is not a speed test):

Your TCP Window limits you to: 20557 kbps (2570 KBytes/s) @ 200ms
Your TCP Window limits you to: 8223 kbps (1028 KBytes/s) @ 500ms

MTU Discovery (RFC1191) = ON

Time to live left = 48 hops
TTL value is ok.

Timestamps (RFC1323) = OFF
Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349) = 00000000 (0)

[trogers]

Your RWIN has been set too high, and is applicable only for 10 mbps and above.

Try the following with TCP Optimizer:

General Settings tab:
Custom settings - check
Modify All Network Adapters - check
network adapter selection - your NIC
MTU 1500
TTL - 64
TCP Receive Window - 64240
MTU Discovery - Yes
Black Hole Detect - No
Selective Acks - Yes
Max Duplicate ACKs - 2
TCP 1323 Options:
Windows Scaling - uncheck
Timestamps - uncheck

Advanced Settings tab:
Max Connections per Server - 10
Max Connections per 1.0 Server - 20
LocalPriority - 1
Host Priority - 1
DNSPriority - 1
NetbtPriority - 1
Lan Browsing speedup - optimized
QoS: NonBestEffortLimit - 0
ToS: DisableUserTOSSetting - 0
ToS: DefaultTOSValue - 80
MaxNegativeCacheTtl - 0
NetFailureCacheTime - 0
NegativeSOACache Time - 0
LAN Request Buffer Size - 32768
Then select "Apply Changes" and reboot to take effect

[lem53]

That seemed to help when I applied the settings. I am supposed to be upgraded later this month to 5 meg speed, do I keep those same settings that you gave me in the above message for that upgrade? I don't suppose a 5 meg will do all that much in terms of speed.

[trogers]

That seemed to help when I applied the settings. I am supposed to be upgraded later this month to 5 meg speed, do I keep those same settings that you gave me in the above message for that upgrade? I don't suppose a 5 meg will do all that much in terms of speed.

You can test speed a few days after the upgrade to see if your speed reaches 4.5 mbps. If not, use the same custom settings with just these 2 changes:

TCP Receive Window - 128480
Windows Scaling - checked

[lem53]

Thanks very much for the help!