Cablenut    dslnuts

Software · Discussion Forum ·

       Thursday, 09-Dec-2021 03:42:16 Central Standard Time


The answers to the following questions are very important when posting asking for assistance, if you answer them accordingly it will save you and us alot of time in helping you get your connection optimized quickly and easily.

1. Download Cablenut.

2. What type of connection do you have? i.e. 56K, ISDN, DSL (PPPoE or not), Cable etc.

3. Who is your ISP and what is your advertised speed from them? i.e. & 3000/256 - this is advertised in kilobits per second. If you don't know your caps please provide us with a link to your ISPs homepage.

4. What are your current settings now? Do a TCP/IP Analyzer test and copy and paste the results (remember to XXXXX out your IP address) here.

5. What kind of speeds are you getting now? Do 10 speed tests from Speakeasy (choose the location nearest to you) clearing your internet temp files prior to each test, and give us the average of your top 5 tests. This will give you a good baseline to go by but remember speed tests are not 100% accurate.

6. Please tell us your operating system i.e. 95, 98, 98SE, ME, 2K or XP.

Remember your goal is to get about 90% of your rated speed, sometimes depending on factors beyond your control i.e. routers, servers, line quality etc. it just isn't gonna happen, no matter what you do.

The following are my suggested settings in Cablenut for 2K & XP:

DefaultReceiveWindow = multiply your ISPs download caps in kilobytes by 1024
DefaultSendWindow = multiply your ISPs upload caps in kilobytes by 1024
DisableAddressSharing = 1
InitialLargeBufferCount = 100
InitialMediumBufferCount = 240
InitialSmallBufferCount = 320
LargeBufferSize = 81920
MaxFastTransmit = 64000
MediumBufferSize = 15040
PriorityBoost = 0
SmallBufferSize = 1280
TransmitWorker = 32
FastSendDatagramThreshold = 4096
EnableFastRouteLookup = 1
EnablePMTUDiscovery = 1
IgnorePushBitOnReceives = 0
GlobalMaxTcpWindowSize = use the calculator to find your best value*
MaxFreeTcbs = 8000
MaxHashTableSize = 16384
MaxNormLookupMemory = 5000000
SackOpts = 1
SynAttackProtect = 1
Tcp1323Opts = 0 (set to 1 if TcpReceiveWindow is 65535 or higher)
TcpLogLevel = 1
TcpMaxDupAcks = 3
TcpMaxHalfOpen = 100
TcpMaxHalfOpenRetried = 80
TcpRecvSegmentSize = 1460
TcpSendSegmentSize = 1460
TcpTimedWaitDelay = 30
TcpUseRFC1122UrgentPointer = 0
TcpWindowSize = use the calculator to find your best value*
MaxConnectionsPer1_0Server = 20
MaxConnectionsPerServer = 10
DefaultTTL = 64
DisableUserTOSSetting = 0
TcpMaxDataRetransmissions = 6
DefaultTOSValue = 92

The following are my suggested settings in Cablenut for 98 & ME:

BcastNameQueryCount - 1
BcastQueryTimeout - 100
BSDUrgent - 1
CacheTimeout - 600000
DefaultRecvWindow - use the calculator to find your best value*
DefaultTTL - 64
EnableDNS - 0
GlobalMaxTcpWindoSize - use the calculator to find your best value*
KeepAliveInterval - 500
KeepAliveTime - 14400000
Lanabase - 0
LocalCopyMade - 1
MaxConnections - 64
MaxConnectRetries - 5
MaxDataRetries - 99
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 (set to 1 if DefaultRecvWindow is 65535 or higher)
TcpTimedWaitDelay - 30
MaxDupAcks - 3
DefaultTOS - 92
IGMPLevel - 2
MaxConnectionsPer1_0Server - 20
MaxConnectionsPerServer - 10

98 & 98SE users need the vtcp.386 patch.

*Remember once you have found the optimum value here try and use the formula above and multiply the value you calculated by 2, 3 or a maximum of 4 to see if it helps improve your connection. Also take note above where I say to use your caps in kilobytes to find the optimum values, when you see your advertised speeds from your ISP they are shown in kilobits i.e. 3000/256 and you must divide those values by 8 to find the value in kilobytes then multiply it by 1024.

For the definitions of all the values in Cablenut:
2K & XP
98 & ME

The Windows 2000 White Papers

Recommended websites for tweaking, troubleshooting & learning:

Carrick Solutions - PPPoE DSL
Navas Cable & DSL Tuning Guide
Axcel216's MaxSpeeedGuide
Tweak Central
Pure Performance
Tom's Hardware

Recommended utilities & applications:

Ontrack System Suite 4.0
Norton Antivirus 2002
jv16 Powertools
Free Surfer
Sygate Personal Firewall Pro
Ad Aware
NTI Backup Now
Internet Sweeper Pro

MTU Values
The Maximum Transmission Unit value should be set accordingly: 56K - 1500/ Normal DSL - 1500/ PPPoE DSL - 1492/ XP PPPoE DSL - 1480/ Cable Modem - 1500.

If your MTU value is not showing up as the correct value try the following to fix it: These fixes are for different OS's so it may not pertain to you. First try here.

AOL MTU Fix:*this can also needs to be changed even if AOL has been uninstalled

 \NdisWan\Parameters\Protocols\0 - look to the right for the value named "protocol MTU" and change it to the appropriate MTU value for your connection.

DSL WinPoet MTU Fix:


Where "n" is a number like 0001, 0002, etc. Look for the 000? folder, with the "iVasion PoET Adapter" in it. (To the left of which it will say, "DriverDesc".)

you should see TunnelMode = 1

Double click on TunnelMode, and change the 1 to a 0.

DSL Enternet MTU Fix:

/Class/Net/000n/Ndi/params/MaxFrameSize/"max" ....

Where "n" is a number, and the registry directory for your Network Telesystems PPPoE Adapter (NTSP3 adapter). Now the thing that you want to modify is the "max" string in that 000n directory, change it to 1492.

Now go to - Start - Settings - Control Panel - Network - Network Telesystems Enternet PPPoE Adapter (NTSP3). Click on the advanced tab and change "MaxFrameSize" to 1492.

Other places in the registry to make sure the MTU value is set properly:


\Class\Net\0000 "IPMTU"= set to proper MTU value.


\Class\Net\0000\Ndi\ params\IPMTU = set it to proper MTU value.


\Class\Net\0002 "IPMTU"= set it to proper MTU value.


\General\"internetMTU"= set it to proper MTU value.


TCPReceiveWindow - Determines how much data the receiving computer is prepared to get. A TcpReceiveWindow value that's too large will result in greater loss of data if a packet is lost or damaged. A too small of a value will be very slow, as each packet will have to be acknowledged before the next packet is sent. If each data packet had to be acknowledged before another could be sent, then performance could suffer due to the delay time needed for the data packet to reach the receiver plus the time needed for the acknowledgment packet to get back to the sender. To avoid this delay, the sender is allowed to keep transmitting data packets prior to receiving acknowledgments up to a maximum "window" size advertised by the receiver, normally large enough for several packets. The larger the window, the more packets that can be sent before needing an acknowledgment; however, larger windows can require more packets to be retransmitted when a transmission error occurs. Hence, the receive window size needs to be large enough to keep data flowing continuously, but not excessively large.
MTU - (Maximum Transmission Unit) Is the greatest amount of data that can be transferred in one physical frame on the network. If a packet that has a smaller MTU than the packet's frame length is sent, fragmentation will occur. 

MSS - (Maximum Segment Size) Defines the largest segment of TCP data that the Winsock is prepared to receive. When a connection is established, the two ends agree to use the smaller of each end's value. Because headers are typically 40 bytes, set the MSS to 40 less than the MTU. 

DefaultTTL - A Windows Registry value that specifies the default Time To Live set in the header of outgoing IP packets. TTL determines the maximum amount of time an IP packet can live in the network without reaching its destination. It is effectively a limit on the number of routers an IP packet may pass through before being discarded.

Tcp1323Opts - Large window support (supported only in Windows 98 and later). Used when an application requests a Winsock socket to use buffer sizes greater than 64K. In previous implementations the TCP window size was limited to 64K, this limit is raised to 2**30 through the use of TCP large window support as defined in RFC1323 and implemented in Winsock 2. Tcp1323Opts also controls Timestamps. 

SackOpts - Selective Acknowledgements (RFC 2018). Selective acknowledgements allow TCP to recover from IP packet loss without resending packets that were already received by the receiver. Most useful when employed with TCP large windows.

MaxDupAcks - Fast Retransmission and Fast Recovery of TCP connections that are encountering IP packet loss in the network. Allow a TCP sender to quickly infer a single packet loss by reception of duplicate acknowledgements for a previously sent and acknowledged TCP/IP packet. This mechanism is useful when the network is intermittently congested. The reception of 3 successive duplicate acknowledgements indicates to the TCP sender that it can resend the last unacknowledged TCP/IP packet (fast retransmit) and not go into TCP slow start due to a single packet loss (fast recovery). 

PMTU Discovery - (RFC1191). Determines whether TCP uses a fixed, default maximum transmission unit (MTU) or attempts to find the actual MTU. Under Windows 9x, if the value of this entry is 0, TCP uses an MTU of 576 bytes for all connections to computers outside of the local subnet. If the value of this entry is 1, TCP attempts to discover the MTU (largest packet size) over the path to a remote host. 

AFD (ancillary function driver) - AFD.sys is the Ancillary Function Driver which basically acts as an entry point for Winsock functions to get to TCPIP.sys. These values are in Cablenut and are only valid in NT based Operating Systems (NT, 2K & XP).


Proper TcpReceiveWindow Formula:

(Maxium Bandwidth x Maxium Anticipated Latency) / 8

Example of a Cable connection with a 1500 download cap with an Anticipated Latency of 100 ms:

(1500 x 100) / 8 = 18750  To make it a multipule of MSS divide by 1460:

18750 / 1460 = 12.84246  Then round up to the nearest even whole number:

14 x 1460 = 20440       

This is what is sometimes called the base TcpReceiveWindow value. From here it can be increased to take advantage of Windows Scaling if the value is 65535 or greater. 

18980 x 2 = 40880 
18980 x 3 = 61320 
18980 x 4 = 81760  MAX TcpReceiveWindow

*Remember when calculating for your optimum TcpReceiveWindow that latency can possibly rise as high as 300-500ms during a large download and if your TcpReceiveWindow is at least as large as your caps X 500 then no increase in it will produce a faster speed. A HUGE TcpReceiveWindow DOES NOT increase your download speed at all, a value larger than defaults is always better but there is a point at which you will not increase your speed with increasing this value.

To get your maximum anticipated latency ping about 10 of you favorite sites. To ping a site open a command prompt and type - ping (for example).

Speed Test
Here. Choose the location nearest to you and do 10 tests clearing your temp files after each one and use the average of the top 5.


Win98/ME: to change to half-duplex:

* Open Control Panel.
* Double-click Network.
* From the scrollable list, select your Ethernet adapter (rather than any dial-up) with a green icon.
* Click the button Properties.
* Click the tab Advanced to bring it to the front:
* In the Property box, the property name to be selected varies according to model of ethernet card. Examples are: Network Link Selection, Media Type, Connection Type, Duplex Mode, or any similarly-named property which can have Values looking like Auto-Negotiation, or 10BT, or 10BaseT.
* In the Value box, select a value which either (a) explicitly says half-duplex or semi-duplex, or (b) at least does not say full-duplex [e.g. 10BaseT on its own is OK]. If there is a choice between 10 and 100 with half-duplex, choose the 10. Do not choose 10Base5, 10Base2, or AUI.
* Click OK to exit the Adapter settings.
* Click OK all the way out - you might need to restart.

Windows 2000 or XP: to change to half-duplex:

* Open Control Panel.
* Double-click Network and Dial-up Connections.
* Identify the icon for your cable modem connection: usually Local Area Connection.
* Right-click that icon and select Properties.
* Under the ethernet adapter icon, click the button Configure.
* Click the tab Advanced to bring it to the front:
* In the Property box, the property name to be selected varies according to model of ethernet card. Examples are: Network Link Selection, Media Type, Connection Type, Duplex Mode, or any similarly-named property which can have Values looking like Auto-Negotiation, or 10BT, or 10BaseT.
* In the Value box, select a value which either (a) explicitly says half-duplex or semi-duplex, or (b) at least does not say full-duplex [e.g. 10BaseT on its own is OK]. If there is a choice between 10 and 100 with half-duplex, choose the 10. Do not choose 10Base5, 10Base2, or AUI.
* Click OK to exit the Adapter settings.
* Click OK to exit the Connection properties.


This tweak will help web pages load faster, it has no real effect on download speeds, just helps your pc look up websites faster thereby speeding up how fast the page loads and making websurfing more enjoyable.

Navigate to this registry entry and change the following settings:

For XP & 2K



For 98, 98SE & ME



On the right for ALL OS's change these entries: (ALL values are HEXIDECIMAL)

Class = 1
DnsPriority = 1
HostsPriority = 1
LocalPriority = 1
NetbtPriority = 1

To change the value right mouse click on the value and select modify and enter the values above once you have done all of them reboot to take effect and see how fast your pages load.

For 98 & ME they should all look like:

01 00 00 00


1. Open Internet Explorer and select Tools - Internet Options - under the General tab in the Temporary Intenet files section select the Settings button.     

Select "Every visit to the page" and set the amount of disk space to use: to no more than 80MB. Now select the Connections tab and select LAN Settings make sure EVERYTHING there is unchecked and select OK.

2. For IE6 ONLY - select the Privacy tab and choose Advanced check the box "Override automatic cookie handling" and for First-party Cookies - Accept, Third-party Cookies - Block and check "Always allow session cookies. Now NO MORE SPYWARE COOKIES.

3. Another thing to do about once a week if you modem is on 24/7 is to power cycle your modem, just completely disconnect power from it for atleast 15 seconds and then power it back on.

4. Delete your temporary internet files regularly.

5. DSL users may want to check out the DSL Wiring Guide for possibly increasing your DSL speed.

6. By default Windows 2K & XP cache everything in the DNS cache service, both correct and faulty DNS lookups. To increase performance by eliminating the caching of faulty DNS lookups, change the following values from whatever their original values are to zero.   




7. Always connect your modem via ethernet (Network Interface Card) instead of USB, ethernet is faster and much more stable. Also ALWAYS make sure you have the latest drivers for your NIC from the manufacturer NOT Microsoft, alot of times the drivers from the manufacturer have advanced settings that help optimize the performance of your NIC that the native Microsoft drivers don't have.

8. Download and update then do a scan with SpyBot & Ad Aware 6.0 to remove any spyware then install and SpywareBlaster to stay spyware FREE.
 Spyware Kills your connection   Sites that use it here's what you can do


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