slow cable speed

kidd · Post by **kidd** » Sun Nov 18, 2001 3:47 pm

Test running.....
** Speed 201(down)/na **
(At least 4 times faster than a 56k modem)
Finish. <--- that's the speed i get on the speed tests..
--------------------------------------------------------------------
here's my analyzer settings

MTU = 1500
MTU is fully optimized for broadband.

MSS = 1460
Maximum useful data in each packet = 1460, which is equal to MSS.

Default Receive Window (RWIN) = 513920
RWIN Scaling (RFC1323) = 3 bits
Unscaled Receive Window = 64240
RWIN is a multiple of MSS
Other values for RWIN that might work well with your current MTU/MSS:
256960 (MSS x 44 * scale factor of 4)
128480 (MSS x 44 * scale factor of 2)
64240 (MSS x 44)

bandwidth * delay product:
Your RcvWindow limits you to: 20556.8 kbps (2569.6 KBytes/s) @ 200ms
Your RcvWindow limits you to: 8222.72 kbps (1027.84 KBytes/s) @ 500ms

MTU Discovery (RFC1191) = ON

Time to live left = 52 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 00000000

i'm running on a system w/

windows 2000 (all patches and updates installed)
all the sg_tweaks for win2k

system configs are

AMD athlon 1.2Ghz
2x256MB PC2100 DDR
linksys ethernet card -> hooked up to a linksys 4port router -> hooked up to the tobisha PCX1100U cable modem

before my system upgrade to win2k (from win98se)
my speed was running fairly fast... but lacked the stability... so i did a full clean to win2k and installed all the service patchses...

but now... my connection seems to lag pretty bad
before my upload speed was at least 40Kbps which isn't bad but not all that great either and my download sleep was around 250Kbps that's slow too... but my speed tests on the old OS was going at 3-4Mbps...

so i was wondering what could be the problem...
i checked my isp and everything seemed to check out fine don't know what could be the cause... anyone know?

garbage · Post by **garbage** » Sun Nov 18, 2001 4:25 pm

i have and still have the same exact problem. when i was in 98, i could download over 500k/s+ any time i wanted to, day or night. now that im in xp, it seems im capped at 390k/s whenever i try. the other day for some ****ing weird reason, it went back to those sweet speeds (got over 600k/s) but after i rebooted, it was back to **** speed again. i did all the tweaks, nothing seemed to help. if you find anything, let me know.

mnosteele52 · Post by **mnosteele52** » Sun Nov 18, 2001 5:06 pm

Check my post Fyi, same thing happened to me and what I posted fixed my speed.

earthmofo · Post by **earthmofo** » Sun Nov 18, 2001 5:20 pm

Garbage, what's your RWin value?

Kidd, your RWin may be too high. Try 51100, it's very fast. The only time a high RWin value should be used is if you're experienceing slow pings or packet loss. If pings are below 100 ms with no packet loss then a smaller RWin value works best.

I have Windows XP installed and my RWin value is only 64240. I'm getting speeds around 4 Mbits.

HalfLifer · Post by **HalfLifer** » Sun Nov 18, 2001 5:24 pm

Originally posted by earthmofo
Garbage, what's your RWin value?

Kidd, your RWin may be too high. Try 51100, it's very fast. The only time a high RWin value should be used is if you're experienceing slow pings or packet loss. If pings are below 100 ms with no packet loss then a smaller RWin value works best.

I have Windows XP installed and my RWin value is only 64240. I'm getting speeds around 4 Mbits.

kidd · Post by **kidd** » Sun Nov 18, 2001 5:33 pm

thank you guys... will try that and reboot and see how it turns out...

okie line tested... rebooted...
my speed did seem to increase by some bits... but...
still seems slow...
could it be that i should lower my mtu?
but how do i do that in win2k?
or should i raise/lower my RWIN setttings?

btw... could the router setup affect the speed too and uhmmm what other settings should i check for?

garbage · Post by **garbage** » Sun Nov 18, 2001 6:07 pm

so i tried mnosteele52 said to do, cept my settings were already set on "auto sense" so i tried the other settings and they just decreased my speed. if anyone has ANY ideas on what to do, please share! heres the results for the tcp/ip analyzer:

TCP options string = 020405b40103030201010402

MTU = 1500
MTU is fully optimized for broadband.

MSS = 1460
Maximum useful data in each packet = 1460, which is equal to MSS.

Default Receive Window (RWIN) = 256960
RWIN Scaling (RFC1323) = 2 bits
Unscaled Receive Window = 64240
RWIN is a multiple of MSS
Other values for RWIN that might work well with your current MTU/MSS:
513920 (MSS x 44 * scale factor of 8)
128480 (MSS x 44 * scale factor of 2)
64240 (MSS x 44)

bandwidth * delay product:
Your RcvWindow limits you to: 10278.4 kbps (1284.8 KBytes/s) @ 200ms
Your RcvWindow limits you to: 4111.36 kbps (513.92 KBytes/s) @ 500ms

MTU Discovery (RFC1191) = ON

Time to live left = 53 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 00000000

mnosteele52 · Post by **mnosteele52** » Sun Nov 18, 2001 7:01 pm

Your settings look fine, that is what I have set and it works best for me, something you might want to try is download the latest drivers for your NIC if you are using the standard drivers in Win2k, I have found that alot of the "stock" drivers in any OS are either outdated or subpar.

kidd · Post by **kidd** » Sun Nov 18, 2001 7:47 pm

hmmmz thx for the input...
i found that it's probably my cable line itself that's causing the problem...
not 100% sure... but just got off da fone w/ my cable company... they said that that might be the cause of my probs... and they'll have someone come out and take a look at the lines and see if anything is wrong

garbage · Post by **garbage** » Sun Nov 18, 2001 8:10 pm

hmm, maybe i should try a different nic card?

earthmofo · Post by **earthmofo** » Sun Nov 18, 2001 8:39 pm

Garbage, I don't think it's your NIC. Try pinging Speedguide and see if you are getting very slow ping times or packet loss. If times are quick 100 ms or less with no packet loss then use a low RWin value. If pings are over 200 ms then use a higher RWin than you have now.

To ping Speedguide click on Start Menu, Run, type in Command then at the dos prompt type:

ping http://www.speedguide.net -n 10 -l 1460

This will give you a pretty accurate average of your ping time and if you have any packet loss.

FinalRender · Post by **FinalRender** » Sun Nov 18, 2001 8:45 pm

What exactly do these numbers mean?
Your RcvWindow limits you to: 20556.8 kbps (2569.6 KBytes/s) @ 200ms
Your RcvWindow limits you to: 8222.72 kbps (1027.84 KBytes/s) @ 500ms

garbage · Post by **garbage** » Sun Nov 18, 2001 8:52 pm

Ping statistics for 161.58.189.81:
Packets: Sent = 10, Received = 10, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 46ms, Maximum = 84ms, Average = 51ms

how do i know what rwin values to use?

earthmofo · Post by **earthmofo** » Sun Nov 18, 2001 8:53 pm

Kidd, I am running pretty much the same setup as you are. Intel 1.0 GHz, 256 meg ram, Linksys Fast Eithernet NIC, Linksys BEFSR41 V2 router and a Toshiba PCX1100U modem. Do you have CableNut installed? If you do, try putting the RWin in the following 3 places: DefaultReceiveWindow, GlobalMaxTcpWindowSize and TcpWindowSize.

kidd · Post by **kidd** » Sun Nov 18, 2001 9:24 pm

no i don't have cablenut installed...
but was thinking about it... i've seen it around alot in this list... just dunon where to get it...
can you show me where and what's the preferable setting i can use for it?

btw what's the speed that you've been getting w/ RR? or ur cable connection...
when i got off the phone w/ my company... they said my line was capped to 1.5Mbps down and 51.6Kbps up..
that's kinda low.. wonder if it's my line...

FinalRender · Post by **FinalRender** » Sun Nov 18, 2001 9:30 pm

http://www.cablenut.com
than go to Software Section

mnosteele52 · Post by **mnosteele52** » Sun Nov 18, 2001 9:35 pm

Download Cablenut from http://www.broadbandnuts.com and put in the following settings, you can adjust them if needed, but it will give you a starting point. Open up the adjuster and try these settings, leave all other boxes blank, save to registry and reboot.

DefaultRecieveWindow = 256960
DefaultSendWindow = 64240
InitialLargeBufferCount = 100
InitialMediumBufferCount = 500
InitialSmallBufferCount = 800
MaxFastTransmit = 2
MediumBufferSize = 1705
PriorityBoost = 0
SmallBufferSize = 1024
EnablePMTUDiscovery = 1
GlobalMaxTcpWindowSize = 256960
SackOpts = 1
Tcp1323Opts = 1
TcpMaxDupAcks = 3
TcpRecvSegmentSize = 1460
TcpSendSegmentSize = 1460
TcpWindowSize = 256960
MaxConnectionsPer1_0Server = 32
MaxConnectionsPerServer = 32
DefaultTTL = 64

FinalRender · Post by **FinalRender** » Sun Nov 18, 2001 9:38 pm

Can someone explain what these numbers mean?
bandwidth * delay product:
Your RcvWindow limits you to: 20556.8 kbps (2569.6 KBytes/s) @ 200ms

Your RcvWindow limits you to: 8222.72 kbps (1027.84 KBytes/s) @ 500ms

earthmofo · Post by **earthmofo** » Sun Nov 18, 2001 10:31 pm

If you're capped at 1.5 Mbits then then that's as fast as you can get.

I have an Cox@home connection and it's advertised at 3000 down and 300 up.

Latest test from Cox@home test site

Test Your Internet Connection Speed
Your line speed:

4636.4 kbps

568.2 K bytes/sec
To run this test again click Here

I've been as high as 8000 kbps but it's prime time here. It's way over my cap because the node I'm on isn't loaded with other connections.