Just got a cable modem....let the tweaking begin.

[josh3336]

Hi. I just got a cable modem and I am getting 1.6 mbps connection speed on average. I d/l a few patches none seem to help alot.
My settings are:TCP options string = 020405b40101040201030300

MTU = 1500
MTU is fully optimized for broadband.

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

Default Receive Window (RWIN) = 5840
RWIN Scaling (RFC1323) = 0 bits
Unscaled Receive Window = 5840
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)
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: 233.6 kbps (29.2 KBytes/s) @ 200ms
Your RcvWindow limits you to: 93.44 kbps (11.68 KBytes/s) @ 500ms
Consider increasing your RWIN value to optimize TCP/IP for broadband.

MTU Discovery (RFC1191) = ON

Time to live left = 57 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 00000000

I'm not sure exactly what all this means but maybe one of you does. I was wondering if there is anything I can do to obtain a faster connection? By the way I am using windows 98. I'm also using comcast as the service provider.

[mnosteele52]

Download Cablenut from my signature and try the following settings:

BcastNameQueryCount - 1
BcastQueryTimeout - 100
BSDUrgent - 1
CacheTimeout - 600000
DefaultRecvWindow - 32120 or 52560 or 64240
DefaultTTL - 64
EnableDNS - 0
GlobalMaxTcpWindoSize - 32120 or 52560 or 64240
KeepAliveInterval - 500
KeepAliveTime - 14400000
Lanabase - 0
LocalCopyMade - 1
MaxConnections - 99
MaxConnectRetries - 5
MaxDataRetries - 64
NameTableSize - 255
NameSrvQueryTimeout - 100
PMTUBlackHoleDetect - 0
PMTUDiscovery - 1
RoutingBufSize - 146432
RoutingPackets - 100
SackOpts - 1
SessionKeepAlive - 7200
SessionTableSize - 255
Size/Small/Medium/Large - 3
Tcp1323Opts - 0
TcpTimedWaitDelay - 30
MaxDupAcks - 2
DefaultTOS - 92
IGMPLevel - 2
MaxConnectionsPer1_0Server - 40
MaxConnectionsPerServer - 20


:) :D

[josh3336]

Thx for the settings. After setting it up I don't see much improvement I am still getting a 1.5-1.6 connection speed.

[mnosteele52]

Post another TCP/IP Analyzer test if you would, with your RWIN as low as it was you should see a difference. Also read the Help & Tips link in my signature for some other tweaks and suggestions.:)

[josh3336]

TCP options string = 020405b401010402

MTU = 1500
MTU is fully optimized for broadband.

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

Default Receive Window (RWIN) = 32120
RWIN Scaling (RFC1323) = 0 bits
Unscaled Receive Window = 32120
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)
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: 1284.8 kbps (160.6 KBytes/s) @ 200ms
Your RcvWindow limits you to: 513.92 kbps (64.24 KBytes/s) @ 500ms

MTU Discovery (RFC1191) = ON

Time to live left = 44 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 01011100
Precedence (priority) = 010 (immediate)
Delay = 1 (low delay)
Throughput = 1 (high throughput)
Reliability = 1 (high reliability)
Cost = 0 (normal cost)

[mnosteele52]

Yep they did take effect, did you try all 3 different values I gave you? If you are on Comcast their caps are 1500/128 so you might be getting all of that already.:) :D

[josh3336]

what do you mean by 1500/128? Umm no I didn't try them all i just used 32120 so far for both. Do i have to use the same number for both?(32120, 52560, 64240?) Also do i have to restart for the settings to change?

[mnosteele52]

Yes you have to use the same number for both and reboot between each change. 1500/128 are Comcast's caps unless you are paying extra for the package with 3500/384 caps.:) ;)

[josh3336]

1.5mbps is the caps? If so then how am i getting more then that. Whys is the cap so low? I'm gonna reboot with 64240 settings now.

[HenryHand1]

Actually, Comcast raised the download cap to 1800kbps. The upload cap remains the same.

My Speed Test on Comcast (http://speeds.henryhand.com/)

[mnosteele52]

Speed tests aren't 100% accurate, try the OOL ftp download test in the Help & Tips link in my signature and see what kind or results you get. I have had speed test results of 4300 when my caps are 3000, so don't base everything on speed tests.:)

[mnosteele52]

Originally posted by HenryHand1
Actually, Comcast raised the download cap to 1800kbps. The upload cap remains the same.

Thanks for the tip, didn't know that.:D

[josh3336]

What connection speed are you getting mnosteele? Also what is ur provider and how much is it monthly? It seems with 64240
the connection is a little bit slower. I will have to run that connection test you were talking about.

[mnosteele52]

My ISP is Cox, it's $35 a month and my caps are 3000/256, my average speeds are 2600-2800. You also might try 37960 for RWIN.:) ;)

[josh3336]

Thats really good i pay more and have a lower caps. Is that ur cable provider also. I'm gonna try to figure out if there is any other type of cable internet that I can get. For RWIn wouldn't a higher or lower number be better? Like does higher mean better and lower worse or what?

[Mohan-san]

Originally posted by mnosteele52
My ISP is Cox, it's $35 a month and my caps are 3000/256, my average speeds are 2600-2800. You also might try 37960 for RWIN.:) ;)

Damn you Americans, getting broadband connections so cheap. I'd have to pay 6 times as much as you to get a 2mbps connection. Its £149.99 a month!!.

[mnosteele52]

Yes they are my local cable tv provider but I have DirectTV for that. Read the Help & Tips link in my signature and it will explain about RWIN size. In a nutshell, you want it large enough to continuosly receive data but not so large that you get lost packets which cause retransmissions which will slow you down.:) ;)

[josh3336]

Ok, I couldn't find that speed test you mentioned what is the name of it?

[mnosteele52]

Here (ftp://ftp1.optonline.net/pub/test64).:)

[HenryHand1]

From what I have gathered in comcast forums on various sites, Comcast may slowly continue to raise the caps as they get the bugs out of their new network (it used to be part of @home, which had much higher caps), so the current caps might not stick for long.

They have OOL in every town in my area, except mine, and they pay $25 a month and get 10MB/s connections... damn them.

[josh3336]

Their gonna increase the caps awesome. Say I wasn't getting the max with the caps now if i increased my caps would i get a faster connection speed? Is there a site where I can check all the cable internet providers in my area?

[josh3336]

Mnosteele that link doesn't work. Also if my connection is not capped then how come I didn't see a performance gain when I switched my registry?

[mnosteele52]

The link works fine for me, you are capped, all connections are capped.:)

[josh3336]

By "not capped" i meant it to the point where i could not get a better connection. Right now I can since it's less then 1800kbps.

[mnosteele52]

Oh OK, yes you can pay more money for more bandwidth with Comcast if it's offered in your area.:)

[josh3336]

But would that give me a better connection? Like if my connection is not to the point where it needs to be capped now if i get more bandwidth wouldn't my connection just stay the same.

[mnosteele52]

Either your confusing me or I'm confusing you;). The speed you are paying for right now is 1800/128 kilobits per second, you have the option of paying for more bandwidth and if you did your caps would be 3500/384 kilobits per second. Your download speed would be close to double what it is now with the more expensive package.:) :D

[josh3336]

Ok that's what I wanted to know. Because like even though it caps at 1800kbps it doesn't mean ur going to get that speed.

[josh3336]

DefaultReceiveWindow = multiply your ISPs download caps in kilobytes by 1024
If so shouldn't i set the defaultreceivewindow at 1843200?(1800kbps X 1024)?

[Mohan-san]

Originally posted by mnosteele52
The link works fine for me, you are capped, all connections are capped.:)

I bet you couldn't say that about Mr.Gate's connection. ;)

[mnosteele52]

Originally posted by josh3336
DefaultReceiveWindow = multiply your ISPs download caps in kilobytes by 1024
If so shouldn't i set the defaultreceivewindow at 1843200?(1800kbps X 1024)?

For 2K & XP only.:)

[Dragonplus]

Also ... it's kilobytes, not kilobits (8 bits per byte).

[josh3336]

Does any of those tips refer to windows 98? I don't know if I should do some of the stuff its not referring to my o/s. Like:Also add the following entry to your registry:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic
es\AFD\Parameters

Add the parameter BufferMultiplier and give it a value of 400 hexidecimal which will make it 1024.

[mnosteele52]

No they are for 2K & XP only, if you read the link it says that the following tweaks are for 2K & XP only.:)

[josh3336]

Yea, i read the link i just didn't know that was with the above information.

[mnosteele52]

josh3336 I think the point you are overlooking in the formula is, Maxium Bandwidth x Maxium Anticipated Latency. Your latency can rise as high as 300-500ms during a file download that is why it is suggested to multiply your "base" RWIN x2, 3 or 4.:)

[josh3336]

Yea, you are right i did miss that. OK so then:(max bandwidth=1800) X (max anticpated latency= 41) (max ping averaged of 7 sites) / 8 (1800 X 41)/ 8= 9225 9225/1460= 6.3 round up to 8 8 x 1460=11680. 11680 x 2=23360 11680 x 3=35040 11680 x 4=46720 So one of these settings should work best for me? If so i guess i will go with 35040 cause it's in the middle.

[Mohan-san]

Originally posted by josh3336
Yea, you are right i did miss that. OK so then:(max bandwidth=1800) X (max anticpated latency= 41) (max ping averaged of 7 sites) / 8 (1800 X 41)/ 8= 9225 9225/1460= 6.3 round up to 8 8 x 1460=11680. 11680 x 2=23360 11680 x 3=35040 11680 x 4=46720 So one of these settings should work best for me? If so i guess i will go with 35040 cause it's in the middle.

Just try all of them. :)

[josh3336]

As it turns out I just got a response back from comcast on connection speed and it is capped at 1.5mbps. Is that low?

[Mohan-san]

Originally posted by josh3336
As it turns out I just got a response back from comcast on connection speed and it is capped at 1.5mbps. Is that low?

Not as low as 1/2mbps :(

[josh3336]

That's what your cap is?

[illestdynasty]

Comcast did raise its download cap to 1800, but this was only to compensate for network overhead so users would actually see the 1500. They still advertise speeds as 1500/128.