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3. Connection and Tweaking

The highest maximum transfer unit that America Online can support is 1400 bytes. That is also the most optimal MTU for AOL connections. Anything higher than 1400 bytes will require fragmentation of those packets. Thus, you'll encounter connection problems and slow speeds, an overall degradation of your service.

by Meteor Dive See Profile
last modified: 2003-07-26 02:37:27

This ONLY applies if you're using the AOL 6.0 client to connect online on Win9x/ME systems.

To change your MTU to 1400, download DrTCP to your desktop from here.

Set your Dial-up Adapters MTU to 1438 from the Adapter Settings list. If you use ICS, then you will also need your MTU to 1438 under ICS MTU. If you also use a NIC, then set that to 1438 under Adapter Settings as well.

Click Save, Exit and reboot your PC. Run a tweaks test to confirm that your MTU is now 1400.

The reason behind the 1438 MTU value is that there is an awkward 38 byte overhead, which is deducted from the actual value your entered on your dial-up adapters.

In other words, 1438-38 = 1400 - Your actual MTU result.

by redxii See Profile edited by Meteor Dive See Profile
last modified: 2003-07-26 02:41:23

America Online Version 7.0 and higher can be tweaked like AOL 6.0, however the adapter that is installed and used by AOL caps MTU. You can lower MTU below 1400 bytes. 1400 bytes is the highest and most optimal for AOL connections. Tweaking, registry edit, and DRTCP will NOT get the program to have a MTU higher than 1400. The software will reset back to 1400 if it is successfully set higher.

By default, MTU is set to 1400 bytes upon installation of the client.

by thebombs12 See Profile edited by Meteor Dive See Profile
last modified: 2003-07-26 02:46:11

XP Pro sets aside 20% of your bandwidth for QoS.

Reserving 0% bandwidth for QoS-aware programs in Windows XP Pro can boost your broadband speed by 20%. Results will vary and may not work at all for some people. The tweak can be found at TweakXP.com.

My general rule would be that if your speeds are over 80% of your cap, then this isn't affecting you. If you are getting below 80% of your cap, it may help you.

by redxii See Profile
last modified: 2002-07-10 22:47:46

If the upstream is saturated by uploading (e.g., sending a large PowerPoint file to the boss, or running a Napster or other public service), the downstream will drop to about the same speed. This is due to a weakness in the basic TCP Internet protocol, not Cable or DSL per se, and not the service provider.

A symmetrical connection (where the downstream and upstream are the same speed) is ideal for business use. If one person on the network on an asymmetrical connection uploads a large file, then everyone will slow down.

by redxii See Profile
last modified: 2002-07-10 22:47:57

Before taking your speed test results from Speakeasy.net/DSLR seriously when it shows a really slow result, try determining your speed using FTP.

Find a fast FTP server that can support alot of bandwidth. We'll use OOL's FTP as a fine example. Download this file to your desktop or run it from it's current location.

When it gets to about 20%-40% done, take a note of the KB/s and cancel the download.

Multiply the KB/s you got by 8.192 to determine your speed in kbps.
Example: 92.4KB/s * 8.192 = 756kbps.

If your speed appears still to be slow, then it is time to contact your ISP.

List of FTP Sites:
AOL FTP (44.1 MB)
ICQ FTP (10.0 MB)
OOL FTP (64.0 MB)
RoadRunner FTP (49.3 MB)

Note: Depending on your geographical distance from the FTP server, speeds will vary between closer DSLR/Speakeasy.net tests and your result from this method.

If you have anymore fast FTP servers with big files for testing, then message me through DSLR's instant messaging system with the URL. Must be in the U.S.A.

by redxii See Profile
last modified: 2002-07-10 22:48:20

Start a new thread in the BroadBand Tweaks forum and include the 11 questions on the pre-post page so the helpers there can help you squeeze every kilobyte out of your connection. If you wish, you can post in the AOL Plus forum

Additional notes: AOL Plus MTU can only go up to 1454, but using too high of an MTU will cause problems on secure sites, so use a maximum of 1438.

by redxii See Profile
last modified: 2002-07-10 22:48:35

If you happen to purchase a modem from a friend, online, or received a modem for another ISP, don't worry there's still hope!

WARNING!! This should be for advanced users only. This may cause serious problems to your dsl modem if the necessary precautions are not taken. Again, only do this if you find out your modem is unable to sync on your line.

For the SpeedStream 4060/3060:
At this time, there is no defined software to change this.

For the Westell Wirespeed:
At the main screen of the program, hit ctrl+alt+f7.
Proceed to the PVC tab.
The following items are found: VPI and VCI Table.
If you do not know your VPI/VCI contact your local telco. They will tell you; but don't disclose what ISP you use. Otherwise, try these common settings from across the globe:

UK, BellSouth835
Denmark, Orang835
France, Wanado035
Singapore Pacificnet0100

(List Credit to »steve-parker.org)

So if you're in the US, try using either 0/35 or 8/35. One of those settings will allow your modem to sync on the line.

Scroll down on the VPI or VCI.
Go to the VCI or VPI table and select the correct number.
Click EDIT VCI or EDIT VPI and click "enable" and then OK.
Click apply again.
Close and reboot modem.

ActionTec Hybrid:
At the main screen of the program, hit ctrl+p
Go to the configurations tab
configure settings there. they are similar to the one above.

Broadxent Blaster:
Set your device to
In your web browser put
username: USER
configure through the web interface.

If configured properly, the modem should sync.

Feedback received on this FAQ entry:
  • The VPI/VCI for the UK is 0/38, not 0/35 or 8/35 as you have stated.

    2009-10-06 05:15:23

  • What do you change it to? That important part seems to be missing. :-) I've read that it is supposed to be a VPI/VCI of 0/38 for AOL DSL.

    2008-11-13 20:48:23 (Doctor Olds See Profile)

by thebombs12 See Profile edited by Meteor Dive See Profile
last modified: 2008-11-15 03:26:52