What should I expect from an Internet provider?

After you have chosen an Internet Service Provider (ISP), you should receive the following basic information:

1.	A local access phone number

2.	A Login name

3.	A Login password

Optional information would include:

1.	Host and Domain name:
If electronic mail is part of your connection services you will also receive your host and domain name. Your host name can include a POP3 host name and a SMTP host name, which are protocols used to send and receive messages on the Internet, respectively.

2.	The NNTP server name:
Allows you to connect to Internet newsgroups.

3.	Domain Name System (DNS) server and IP address

Access providers who support PPP will generally automatically assign IP address each time you dial in to the access provider. However, some PPP access providers might require manual configuration of an IP address as described in 'Setting the Domain Name System Server and IP Addresses' elsewhere in this chapter. You also need, in most cases, to configure the IP address of the access provider’s DNS server.

All SLIP accounts require you to manually configure an IP address on your computer when you connect.


What do I look for when choosing an Internet Service Provider (ISP)?

In deciding which Internet Service Provider (ISP) to use, you should look for the following:

•	Does the ISP support PPP?

•	Does the ISP offer free technical support?

•	What kind of connection speeds does the ISP support?

•	Does the ISP support 56K modems? V.90 standards?

•	What kind of search tools do they provide?

•	Does the ISP have an adequate number of phone lines and a large enough pipe to the Internet in order to provide good response time?

•	What range of services, such as mail, newsgroups and hosting, does the ISP offer, and at what charge?


Why do I need TCP/IP installed?

TCP/IP is the protocol used by the Internet that makes it possible for different operating systems and networks to communicate with each other over long distances.

To connect to the Internet, you must have TCP/IP installed. You can install TCP/IP when you install Windows 95 using the "Custom Setup Options", or if Windows 95 is already installed, you can install it using the 'Network' icon in Control Panel.

To install TCP/IP

1.	Open the Windows Control Panel

2.	Double-Click on the 'Network' icon, click the Add button.

3.	In the 'Select Network Component Type' dialog box, double-click 'Protocol'.

4.	In the 'Select Network Protocol' dialog box, in the 'Manufacturers' list, click 'Microsoft' and in the 'Network Protocols' list, click 'TCP/IP'. Click 'OK'.


What do I need to connect to the Internet?

To connect a computer running Windows 95 to an Internet access provider, you need to do the following:

•	Obtain an Internet account with an Internet Service Provider (ISP).

•	Install TCP/IP for the Microsoft Dial-Up adapter and Dial-Up Networking

•	Install a modem.

•	Create a Dial-Up Networking profile that connects you to an Internet Service Provider (The Dial-Up profile is where such information as IP address and DNS server information is added).

•	An Internet Browser is highly recommended (Netscape Navigator and Internet Explorer are the most common browsers).


What is the difference between KB/s and Kb/s?

The main units of modem speed are:

•	KB/s or KBps = kilobytes per second

•	Kb/s or Kbps = kilobits per second

When transmitted over a modem, there are ten bits per byte (eight data bits plus a start bit and a stop bit). So if one modem seems ten times faster than another, it's because different units are being used.


What are typical 56K connect speeds?

Although your results will depend heavily on many different factors (phone line quality, ISP connection types, traffic, etc…) typical results are:

•	42,000bps to 46,666bps for modems using the Rockwell K56flex chipset.

•	44,000bps to 52,000bps for modems using the 3COM X2 chipset.


How can I test actual modem performance?

If done correctly, file downloads are an excellent way to test modem performance. The trick is to make sure you're really testing the modem's raw transfer rate, and not some other factor that you're not aware of.

Here are some guidelines for download testing:

•	USE AN FTP PROGRAM
Web browsers often fluctuate to much to accurately measure download rates.  FTP is more reliable. Note that some FTP programs reports download speeds in Kilobits per second (Kbps), while others use Kilobytes per second (KBps).

•	DOWNLOAD A COMPRESSED .ZIP FILE
If the file you download isn't compressed, hardware data compression in the modem will kick in, leading to erroneous results.  Different file types compress to different degrees, so if you download a Microsoft Word file as opposed to a QuickTime movie, there's no way to compare the results.  Use a .zip (PKZip/WinZip) file for your tests.

•	DOWNLOAD A FILE THAT'S AT LEAST 200K
A file size of at least 200K will help minimize the effects of a slow start. The larger the file, the more accurate the results.

•	DOWNLOAD FROM YOUR LOCAL FTP SERVER OR UNIX DIRECTORY
A local server is one that's run by your ISP, not on the other side world.  If you download a file from across the Internet, you're testing your ISP's connectivity to the Internet just as much as you're testing your modem.

Most ISPs have FTP sites at ftp.ispname.com.  If you're on AOL, for instance, go to ftp.aol.com to download files. There will usually be a directory called 'pub', that contains downloadable files.


What are the status commands for my X2 modem?

The following example of information you can receive from your X2 modem is available AFTER the current dial-up session is terminated.

•	Initiate a connection.

•	Disconnect

•	Issue an ATI6 and ATI11 in your terminal program (such as HyperTerminal).

The 'ATI6' command will return the following information

Chars sent:	580

Chars Received:	49642

Chars lost:	0

Octets sent:	360

Octets Received:	26533

Blocks sent:	191

Blocks Received:	805

Blocks resent:	0

Retrains Requested:	0

Retrains Granted:	0

Line Reversals:	0

Blers:	1

Link Timeouts:	0

Link Naks:	0

Data Compression:	V42BIS 2048/32

Equalization:	Long

Fallback:	Enabled

Protocol:	LAPM SREJ 128/15

Speed download/upload: 46666/31200
(shows the highest download/upload connect speeds.)

Last Call duration:	00:04:34

Disconnect Reason:	Escape code

The 'ATI11' command will return the following:

The ATI11 command shows the number of upshifts and downshifts for receive (RX) and send (TX).

Here is a sample using a USRobotics Courier V.Everything Link Diagnostics.

Modulation:	X2/V.34+

Carrier Freq. (Hz):	NONE/1920

Symbol Rate:	8000/3200

Trellis Code:	NONE/64S-4D

Nonlinear Encoding:	NONE/ON

Precoding:	NONE/OFF

Shaping:	OFF/ON

Preemphasis Index:	NONE/0

Recv/Xmit Level (-dBm): 15.7/12.2

SNR (dB):	61.5

Near Echo Loss (dB):	10.2

Far Echo Loss (dB):

Roundtrip Delay (msecs): 26

Timing Offset (ppm):	-1406

Carrier Offset (ppm):	68

RX Upshifts:	0

RX Downshifts:	1

TX Speedshifts:	0

X2 Status:	0000; 0000-0000-0001-0000-0000-0000; 00,00 0031;03


What are the status commands for my K56flex modem?

The following example of information you can receive from your X2 modem is available AFTER the current dial-up session is terminated.

•	Initiate a connection.

•	Disconnect

•	Issue an AT&V1 in your terminal program (such as HyperTerminal).

These are some sample results:

(TX is the transmit (upload) speed. RX is the receive (download) speed.)

TERMINATION REASON:	LOCAL REQUEST

LAST TX data rate:	31200 BPS

HIGHEST TX data rate:	31200 BPS

LAST RX data rate:	46000 BPS

HIGHEST RX data rate:	50000 BPS

Error correction PROTOCOL:	LAPM

Data COMPRESSION:	V42Bis

Line QUALITY:	127

Receive LEVEL:	014

Highest SPX Receive State:	00

Highest SPX Transmit State:	00

EQM Sum Value:	00A2

RBS Pattern detected:	00

Data Rate Dropped in kbps:	00

Digital Pad Detected:	None


Why do I connect fast but seem to slow down after a while?

Initial connect speed can be deceiving. V.34 and 56K modems can and do shift their speeds up and down during the course of the call to respond to changing phone line conditions. Some modems connect very aggressively at high speeds, but are then are forced to lower their speed to a more stable level.  Others may connect conservatively and upshift.

For example: Using a 56K modem, you may connect at 50,666bps but during your time online, congestion causes your connection to slow down to 28800bps. Once the congestion has cleared your speed will try to climb back up to the speed you originally connected at.


Why does my 56K modem have problems connecting to my ISP's phone numbers?

When a 56K modem is used to dial into a V.34 modem bank (33.6 or lower), the modem will still try to negotiate a 56K connection even though it's impossible.

If this is the case and your ISP does not have specific phone numbers for 56K modems, you may want to disable the X2 or K56Flex feature to tell the modem to not attempt a 56K connection.

To disable in X2 modems

•	These go at the end of your current Init string.

•	S32=32 (for Sportster: disables X2)

•	S32=34 (for Sportster: disables X2 and enables V.8 mode)

•	S58=1 (for Courier)

•	In addition, there has been some success with these commands.

•	S15.7=1

•	&N16&U8

•	&N16

•	S32.5=1

To disable in K56flex modems

•	For Rockwell-based K56flex modems: Add +MS=11,0,9600,33600 to the end of your modem Init string.

•	For Lucent-based K56flex modems: Add S38=0 to the end of your Init string.


Why does my USR Sportsters get slower and slower, and then suddenly disconnect?

This is the X2 version of 'Spiral Death Syndrome'.

The fix in most cases is to add S15=128 to the Init string to disable V.42 hardware error correction.

It may also be necessary to add &K0 to the Init string to disable V.42bis hardware data compression.

WARNING: Using these tips, your Internet performance may suffer when downloading non-compressed files.


What does DTE and DCE speed mean?

DTE:

DTE stands for Data Terminal Equipment and it refers to the computer or terminal to which the modem is connected.

The speed used by the computer COM port or terminal port to communicate with the modem is referred to as the DTE speed.

DCE:

DCE stands for Data Communications Equipment and is synonymous with modem.

DCE speed refers to the carrier speed used by the modem to communicate over telephone lines.

In a V.34 modem, the carrier speed over the phone line is 33,600 bps while the DTE speed should be set for 115,200 bps in the data communications software to achieve maximum performance.  Speed buffering combined with flow control built into the modem regulates the flow of data between DTE, DCE and the phone line.  Data compression effectively multiplies the carrier speed allowing a modem using a 33,600 bps carrier speed to achieve data throughput of up to 115,200 bps by compressing data up to 4 times before transmission throughput over the phone line at 33,600 bps.

Note: Sometimes the connect speed reported by your dial-up connection (the DCE) will be mistakenly reported as the DTE value. In other words, your 33,600bps connection might be mistakenly reported as a 115,200bps connection.


Why does my modem connect at 26,400 bps or slower?

Telephone line signal quality varies widely from one area to another and from one call to the next.  All V.34 modems probe the telephone line during the initial 'handshake' sequence to determine the optimum carrier speed to utilize based upon the quality of the received signals.

Most name brand 33.6 modems feature a robust V.34 technology that attempts to connect at the highest possible speed.   When calling local numbers your modem should typically connect at speeds of 26,400 to 33,600 bps.  When calling long distance numbers, connect speeds may vary between 19,200 and 33,600 bps.


Why doesn't my connection ever connect at 56K speeds?

FCC regulations limits performance to 53.3K.

There is an FCC regulation that prevents all devices attached to the telephone network from exceeding a certain power output.  As a result, the modems have to scale back the output, which has a direct effect on the speed at which it can transfer data.  Currently, they have the server modem limit set to 53,333 bps.  This does not mean that you will not be able to hit the higher speeds, it simply decreases the likelihood.

Also, there are many factors that can influence the connection rate and the speed at which you transfer data.  Even though one end of the connection is pure digital, there are issues that can hamper an X2 connection, while not necessarily preventing it altogether.  Essentially, the qualities of the phone line plays an essential role in the speed of the connection.


How do I change the COM and IRQ settings for Winmodems?

Changing COM and IRQ setting for Winmodems is not the same as other devices. To change the COM and IRQ settings you must follow these steps:

1.	Click Start/Settings/Control Panel.

2.	Click on the Winmodem icon.

3.	Select Properties.

4.	Change the COM port to the desired setting.

5.	Your system should be restarted.

To change the IRQ settings you must follow these steps:

1.	Click Start/Settings/Control Panel/System/Device Manager.

2.	Select Ports and choose the Winmodem on COM?

3.	Select Properties and resources.

4.	Un-Click on AUTOMATIC settings.

5.	Change the IRQ to the desired setting.

6.	Your system should be restarted.


Why is my Winmodem installed on COM5?

The system may not have one of the standard COM ports (1 through 4) available, or an available IRQ for the Modem to use.

COM5 is an invalid setting for Winmodems and must be changed.

If it shows that all COM ports 1 to 4 are used, one of these ports must be cleared.  If this is the case contact your computer manufacturer to disable at least one port.  Then re-install the Modem, but you should un-install the current Winmodem in the control panel using the uninstall feature.

If COM ports 1 and 2 are used and there are no listings for COM 3 and 4 there may be a problem with Windows 95, and it is recommended to manually change the COM port from COM5 to COM3 or COM4.  Be sure to restart the system after making the changes.


How do I check for line noise on a phone line?

Listening for noise
First you need to get rid of the dial tone so you can really listen to the line.  Dial a number, any number but obviously one which is valid for your area, so that you don't get the dial tone replaced by a busy signal.  The easiest and most common across all areas is a '1'.  Is your dial tone gone?  Now listen and really concentrate, because you are only going to get 30 seconds, before times run out and gets replaced by a busy signal.

This is the first major step to checking if you have a good line for a modem or not.  Is it quiet?  No  pops, bangs, crackles, creaking, or faint voices in the background from other people's conversations.

All or any of these noises will cause you a problem on a high speed modem.

Just what are these noises?
Well, it can be something as simple as a loose screw on a connector block somewhere between you and the exchange, or water getting into one of Telco’s cable ducts and the waterproofing (around the cable joints) has started to break down.  You could have a bad connection in the house somewhere, and not necessarily on the line extension that's feeding your modem.  Other people's conversations (called 'crosstalk') are not so easy to pin down, and are usually more likely to be further 'into the system' before the source becomes apparent.

Check the Phone
Let's presume you have one of these noises to some greater or lesser degree.  Next you need to check the phone itself.  After all, if it's just the phone causing the noise, it won't affect the quality you get from the modem now.  If you have a spare phone, take it and plug it into the same socket and then check for noise again.  If you don't have a spare phone, it might be worth heading to the local electronics store to pick up an inexpensive phone.

Checking the Modem connector
Let's assume now that you are happy with the perceived 'quietness' of the line.  Now you move to the modem.  How can you check if you have a dodgy plug or socket associated with the modem?  Well, surprisingly, it's reasonably simple but you'll need to be fairly quick in carrying out the next 'test'.

What you are going to do is to get the modem to go on line, but not actually dial out a full number (similar to what you did just now but using the modem instead).  To do this you'll also need to have a phone plugged in, too, that's fairly near to where your PC/Modem are.  Don't pick up the phone yet.

You're about to enter a command string to the modem, so you'll need to have the PC powered up and talking to the modem with whatever piece of communication software you use.  Don't dial out a number.

The following steps will require AT commands to be sent to the modem.

Now type this:  'ATX0D1;' (without the quotes) and what you should hear (if you have the modem's speaker on) is that the modem will pick up the line (dial tone heard), then dial a 1 and finally drop back to command mode (OK prompt on your screen) while holding the line open.  The next bit is easy or more difficult depending on the accessibility of your modems’ leads. i.e. internal or external modem.  Now pick up the phone and listen.

This time, it's going to be your modem that may 'time out' before your phone line does.  Check the modem's lead, plugs and sockets by physically getting hold of them and just gently pushing and pulling on the lead at both ends.  You'll find on these type of plugs that there is possibly a couple of millimeters of 'play' even when the plug is fully seated in it's socket.  This is enough for our purposes.  Again, be gentle. If there is a dodgy connection, it won't take a lot of movement before it becomes apparent in the phone you are listening to.

No noise? If the modem hasn't already timed out, drop the line send the  'ATH' command. If you did hear some crackling from that, then you'll need to get that lead replaced.  It could be just the contacts of the plugs that have become a little tarnished.  A good ink eraser with a fairly sharp edge should clean these up nicely

Test for Line level and Eye Quality Monitor.

Modems With a Rockwell Chipset:
You've carried out all the above and you are still getting poor speed connections with your modem.  Now it's going to matter exactly what type of modem you have, and whether it has a Rockwell chipset in it or not. How do you find out? The easiest way (and most standard) is to type either AT&V or ATI4.  If you have a Rockwell chipset, you'll see a complete configuration dump starting with 'Active Profile' then 'Stored Profile 0' followed by 'Stored Profile 1' and finally 'Telephone Number Stores'. The latter should return a couple of rows of checksum digits (up to 4 rows) which are the capabilities of the modem in 'hex.'

If you have a Rockwell chipset, follow this procedure:

1.	Dial into another modem [a BBS or other service provider] from a terminal screen (not automatic with a script - manually)

2.	Do whatever you need to get your Login prompt [if your service does immediate PPP or immediate TELNET, use a different service].

3.	Pause (do nothing) for at least 1 second.

4.	Type '+++' (without the quote marks - just the pluses)

5.	The modem should now have dropped back into command mode and you should be looking at an 'OK' prompt *but* you will still be online.  (You'll need to be fairly sprightly, as you may lose the connection if you aren't quick enough...)

6.	NOW you can type AT%L%Q [Return].  The modem should return 2 figures on successive lines like 20 8 or something.  These are the Line Level (%L) in -dbm and the Eye Quality Monitor (%Q) index.  In the example above, that would be -20dbm (reasonable) and 8 (also reasonable). Higher figures mean worse connections. Anything higher than about -24 with the first, and you'll be seeing bad connections or possibly none at all.  Higher than 15 on the second, and you've got real line problems on your circuit that your Telco should be able to sort out.

When you've finished, you might like to go back online with ATO (not zero) and then log off normally.  You *may* find you get logged off anyway after you've got the response to %L%Q.  If you do get bad figures from these tests, you'll need to contact your Telco to try and get your line improved.

Other Modems:
If you have a USR based modem (and there are some 'badge engineered' models about), then chances are you will be able to use ATI6 for your checking. This can be done either online (see above for how to stay online but get back to command mode...) or offline, as the USR chipset 'remembers' the figures it got from the last connect you made. The bits you are interested in are BLERS.  These are 'Bit Link Error RateS'.  Ideally, this figure should be 0.  If it is 1 or 2 after you have been online for a while, then you probably have nothing to worry about. If it climbs much higher over, say, a 3-4 minute connect, then you are probably suffering from noise or low level or both, as in the Rockwell situation above.  If you want to know what the rest of the figures mean, consult your modem manual.  Unfortunately, the USRs do not give an indication of the actual received carrier level in decibels/milliwatt (dbm).

If you have neither of these types of modem, then you are going to have to consult your manual.

If you've got noise and a low line level, you need to contact your Telco provider.  Explain to them that you are using a modem on your line, you are getting poor cct quality figures from your modem, and that the line level is low.  You are entitled to have this problem corrected.  Make sure that you say there is nothing wrong with your normal voice communications (if that is the case...), otherwise they will just do a normal line check.  If you are on a digital exchange, ask them if you can have the AGC (Automatic Gain Control) turned OFF and your line setting at the exchange, set to position '5'.  In most cases this should give you a good cct and level and cure your connect problems at a stroke.


Why does my modem continue to connect at slow speeds?

Modems rarely connect at their rated speed because connection speeds depend on a variety of items. Here are some considerations:

•	Make sure that the ISP you are using has the support for the modem you are using and is of the same or higher speed than your own. If you are using a 56K modem, the ISP you are using must have support for the same 56K modem technology.  If not, the modem will connect at 28,800 bps. If you try to connect a faster modem with a slower one, it will always default to the slower speed.

•	Sometimes line noise and the quality of the connection can affect the speed at which you connect.  There are four areas of concern:

1.	The inside wiring of the location you using

2.	The phone company that routes the call

3.	The phone company at the location you are calling

4.	The inside wiring of the location you called.

The most likely problems are the wiring of locations you are located at and the one you are calling.  This problem is especially bad for 56K modems.

•	Check to see if the COM port setting is set to the maximum speed supported by the type of modem installed, most new modems should have the COM port speed set to 115,200 bps.

•	Check the flow control, it should be set to Hardware (RTS/CTS).

•	Check the modem initialization string and verify that the connect speed has not been set to a specific rate.
Use the following strings to initialize your modem for high-speed connections with error correction, data compression and hardware handshaking:
AT&F2 or as an alternative AT \N3 &K3 &Q5 &D


Why does my modem keep getting disconnected?

•	Line noise
If you are attempting to make a long distance connection over a bad phone line, line noise may be interfering with the signal.  If the place you are trying to call has another number, try calling it instead.

•	If the problem is occurring no matter what number you dial, check your phone line to make sure there is no extraneous noise.
Replace the cable going from your modem to the wall jack to make sure a kink in the cable isn't causing line noise. Check to make sure no one is picking up an extension. If someone else picks up the phone, it will corrupt your connection, usually forcing your modem to hang up.

•	If the disconnect problem occurs with an internal modem.
Try moving the modem to another slot, the modem maybe affect by noise radiated by the adapter next to it.  This is especially true for the inexpensive modems.

•	Time Limit restriction
Verify that the location you are calling does not have a time limit on the connection.  This often used when the service does not have sufficient resources to support a lot of simultaneous users.

During peak hours (8PM-11PM) most Internet providers will disconnect customers that have been connected for more than 1 or 2 hours.  This will allow other users to have an opportunity to use the Internet service.  Unfortunately, this is a standard policy throughout the internet industry, there will always be a growing amount of clients to serve.

Certain TCP/IP stacks used by Internet access providers will automatically disconnect the user after a period of inactivity. Check the manual or contact the manufacturer of your Internet software to determine if this could be the problem.

•	User Settings
The program will verify that the 'Disconnect a call if idle for more than' check box is not set or it is set to a short time (less then 15 minutes).

•	Call waiting
Review dialing properties for the call waiting.  If not set query the user to determine if they have call waiting feature on the phone.  If they respond yes then make sure that the disable code has been entered in the Dialing Properties.  In Control Panel select the Modem icon, press the Dialing Properties button and check the 'To disable call waiting, dial' check box and enter the correct code for your phone system.


Why doesn't my modem dial out?

The modem gets a dial tone, but is unable to connect to the requested number.  This is often caused by an incorrect phone number or dial-Up networking setting. Try the following suggestions:

•	Verify that the modem installation is correct and connected to a valid phone line.

•	Run the modem test with 'Test Remote' selected.

•	Review the Dial-Up Networking settings, verify that all dial-up sessions are directed at the correct modem.

•	Check that dialing properties are correct.

•	Check to see if you have to dial a special number to access an outside line (for instance, dialing a '9' before the phone number)


Why does my Winmodem install on COM5 when there are other COM Ports free?

A damaged Registry file may only show partial data for a COM Port. The Registry Plug and Play (PnP) files may have been affected by a partial or incomplete install of the Winmodem.

All basic PnP settings may be in use.

Suggestion: Try changing the port manually to see if Windows 95 accepts it.


Why do I get a 'No dial tone' message when attempting to dial into my ISP?

•	Make sure that the wire from the wall phone jack is connected to the modem.

•	Make sure you have an active phone line by connecting a standard telephone and testing it.

•	Try changing the wire with another phone wire.

•	If your modem has both a 'LINE' and 'PHONE' jack, be sure the telephone line extending from the wall goes into the 'LINE' jack.

•	Your modem may have been damaged. The 'No Dial' tone symptom is often the result of a voltage surge that came down the telephone line, especially if the modem used to work on that line.  This is common problem due to thunderstorm activity.  Please contact your modem vendor’s technical support for assistance.


What does the error message 'DSP 1010 ERROR' or 'EPROM Corrupt' mean?

This is an error message for the USR Sportster Winmodem under Windows 95 and indicates that the modem is defective. The message will appear after the Winmodem is installed and you attempt to use it.  Call the modem vendor, as your modem will need to be repaired.


Why doesn't my modem work after I upgraded my motherboard?

Window 95 keeps information about your motherboard and other hardware in a file on your hard disk called the registry.  If you change motherboards the information in the registry will no longer be correct.  This is likely the cause of the modem's erratic behavior.

Suggestion: Windows 95 should be reinstalled in order to refresh the registry with the new motherboard information.


Why can't Windows 95 detect my internal Plug and Play modem?

•	Please review the installation instructions provided with the modem.  If you feel that the modem has either stopped responding modem was detected in your systems, there may be a conflict between your modem and another device.

•	If your computer has a Plug and Play BIOS, you may need to make sure that the Plug and Play features there are disabled. In most cases, this is all that needs to be done.

•	Under Device Manager (Control Panel; System; Device Manager) under System Devices should be listed 'Plug and Play BIOS'. If that is not listed, you should add that option manually:

1.	Go to Control Panel, Add New Hardware

2.	Do not Let Win-95 search for the hardware, Select System Devices from the listing

3.	Select ISA PnP Bus and click on 'Next', Windows should find the Plug and Play modem.


Why doesn't Windows 95 ever detect my modem?

•	Under Windows 95, make sure that the modem is not listed in the Device Manager under 'Other Devices'. If it is, delete it and reinstall.

•	Valid COM Ports are 1, 2, 3, and 4, and valid IRQ’s are 3, 4, 5, 7, and 9.

•	Make sure the key USR1001 is not in the registry.  This can be done by selecting Edit/Find in regedit, and searching for USR1001.  If this key is in the registry, delete it.  (WARNING: Making any changes to the Windows 95 registry can cause major problems. Do this at your own risk! Make sure you have made a backup copy of your registry before starting regedit.)


Why is my PS/2 mouse locking up after installing my internal Plug and Play modem?

The mouse is locking up because the mouse and the modem are both trying to use the same system resources.

Your computer has a Plug and Play BIOS that is setting the modem up to use the same interrupt setting as your mouse.  Try this:

1.	Remove the modem

2.	Disable COM2 on your computer

3.	Remove the COM2 definition in the Windows 95 Device Manager

4.	Reinstall the modem.

The modem should then be able to setup on COM2/IRQ 3 and not conflict with the mouse.  Some experimentation with the Plug and Play settings in the BIOS may be necessary.


Why is my serial mouse locking up after installing my internal Plug and Play modem?

The mouse stops working because the mouse and the modem are both trying to use the same system resources.

It may be the BIOS on the computer is changing your serial port settings, causing the mouse not to work.  In your BIOS/CMOS setup, find your serial port settings.  If your mouse serial port is set to AUTO, change it to COM1/3F8/IRQ4 or COM2/2F8/IRQ3.  This should keep your serial port from changing settings when the PnP modem is installed.

Please consult your computer manual, vendor, or manufacturer for information on changing BIOS settings


Why does my computer or mouse lock up when I attempt to access my modem?

There could be a variety of reasons:

•	The system is locking up because there are two devices trying to use the same system resources.
The resource assigned to the modem is the same as another device. There are no available system resources, to free up resources it will be necessary to disable a device. Refer to your PC documentation for instructions on disabling the internal COM port.

•	There are two device assigned to the same system resource.  This conflict will cause both devices not to work properly.
The resource assigned to the modem is the same as another device. The modem does respond to Plug and Play configuration or it is not Plug and Play compatible.

Refer to the modem documentation for instructions on setting the modem to these setting.

Check the mouse and determine if it a PS/2 or serial mouse.  If it is a PS/2 mouse it may be possible to disable the internal COM port and free that resource for the modem.


Why don't my programs recognize my modem?

The software that you want to use may not be 100% complaint with Windows 95.  The software may require you to select where the modem is located.  This is often the case with America Online or some older software programs.  Check the documentation for instructions on how to select the modem and check with the vendor for an update.


Glossary

DCE:  Data Communications Equipment.  Communications equipment installed in a user's premises responsible for establishing, maintaining and terminating a connection.  A modem is an example.

DNS:  Domain Name Server.  A program that converts a domain name into a unique numerical address or IP Number.

DTE:  Data Terminal Equipment.  A piece of equipment where a communications path ends.  The user's equipment is collectively termed DTE and can include PCs and display terminals.

FTP:  File Transfer Protocol.  The TCP/IP standard, high-level protocol for transferring files from one machine to another.  Usually implemented as applications level programs, FTP uses the Telnet and TCP protocols.

Full duplex:  A channel capable of transmitting in both directions at the same time.

Init string:  A string of commands that initializes the modem and sets the modem defaults.  "AT&F" is the factory default.

IP:  Internet Protocol.  IP is the networking language that connects all of the computers on the Internet.  An IP Number, sometimes called a "dotted quad" is a unique number consisting of 4 parts separated by dots, e.g. 165.113.245.2 which every machine that is on the Internet has.  Most machines also have one or more pseudonyms, or Domain Names that are easier for people to remember.

ISP:  Internet Service Provider.  A company or organization that provides access to the Internet in some form, usually for a fee.

KB/s or KBps = kilobytes per second.  One byte is made up of 8 bits.

Kb/s or Kbps = kilobits per second.

K56flex:  A 56K modem protocol developed by Rockwell/Lucent using their 56K chipset.

NNTP:  News server, usually provided by an ISP.

POP3:  Point of Presence.  A long distance carrier's office in your local community.  A POP is the place where your long distance carrier, or IXC, terminates your long distance lines just before those lines are connected to your local phone company's lines or to your own direct hookup.  Each IXC can have multiple POPs within one LATA. All long distance phone connections go through the POPs.

PnP:  Plug and Play.  The act of attaching a device to your computer that the Windows 95 operating system detects and configures automatically.

PPP:  Point-to-Point Protocol.  A protocol that allows a computer to use TCP/IP to connect to other computers over a standard phone line using a high-speed modem

SLIP:  Serial Line Internet Protocol.  A standard for using a regular telephone line (a "serial line") and a modem to connect a computer as a real Internet site.  SLIP is being replaced by PPP.

SMTP:  Simple Mail Transfer Protocol.  A way of delivering E-mail.

URL:  Uniform Resource Locator. The standard way to give the address of any resource on the Internet that is part of the World Wide Web (WWW). A URL looks like this -- http://www.touchstonesoftware.com/index.htm

V.90:  Standard that will allow X2 modems to communicate with K56flex modems.

X2:  A 56K modem protocol developed by 3COM/USRobotics using their 56K chipset.


How does the V.90 technology work?

Traditional modems assume that both ends of a connection to the public switched telephone network are analog. Data signals are converted from digital to analog and back again, limiting transmission speeds to 33.6 Kbps.

V.90 technology makes a different assumption in that one end of the modem conversation has a pure-digital connection to the phone network  (which Internet Service Providers and corporations already use for remote access) and takes advantage of that high speed digital connection.

By viewing the public switched telephone network as a digital network, V.90 technology is able to propel data downstream from the Internet to your computer at speeds of up to 56 Kbps.  *In this way V.90 technology is different than other high speed modems -- because data is digitally encoded downstream instead of modulated.  This is an asymmetrical method, so upstream transmissions (mostly keystroke and mouse commands from your computer to the central site, which require less bandwidth) continue to flow at the conventional rate of 33.6 Kbps.

V.90 technology is ideal for serious Internet users, because you really need the 56 Kbps speed for downloading those Web pages with sound, video and other large files.

*Actual speeds vary depending on line conditions. Due to FCC limitations, speeds in the U.S. are limited to 53 Kbps.

V.90 also incorporates something called "Line Probing"

The connection sequence also known as "line probing" establishes the clarity of the phone connection. The key to line probing is the assessment of line quality - not necessarily the quality of the connection. The signal to noise ratio improves with the accuracy of the line probe, lowering error rates and improving throughput rates.


How do I upgrade from my current 56k to V.90?

Here's an easy guide to upgrading a 56k modem to the ITU's V.90 56Kbps Standard

Step #1:

Find out if your ISP has upgraded to V.90. Before 56K modem owners can connect to their ISP using the ITU's new V.90 56Kbps standard, the ISP first must implement V.90 in its central-site modem equipment. Those ISPs who have not yet offered any type of 56Kbps Internet access service are also expected to very quickly implement V.90 in the coming weeks and months. Most believe it will be several months until the majority of ISPs finish their upgrade to V.90. Before and after that upgrade is completed, all ISPs who previously offered 56K service will continue to offer 56K service.

Step #2:

Decide if you're really a candidate for an immediate V.90 upgrade -- if you're already happy with your ISP's 56K service and have no immediate plans to switch to another ISP, there is no immediate need to upgrade to V.90.

Step #3:

If you do decide to upgrade to V.90, check with your modem manufacturer regarding specific procedures. The most common procedure will likely be a simple software download from your modem manufacturer's web site, but the exact procedure is up to each manufacturer.

Step #4:

Also have your modem manufacturer describe how your 56K modem will allow you to easily alternate between V.90 and 56K, if necessary.

The upgrade path that many modem manufacturers have developed for their customers is designed to give modem owners backward compatibility with 56K, even after they have upgraded to V.90. The advantage here is that different ISPs will complete their V.90 upgrades on different timetables and this type of upgrade path will ensure that an upgraded 56K/V.90 modem will always make a reliable 56K or V.90 connection at any point during the industry's transition to V.90. Again, the smartest move is to postpone your V.90 upgrade until you have confirmed that your ISP has upgraded to V.90.

Step #5:

Start benefiting from your V.90 56Kbps modem.

If you're already getting great service at one of the thousands of Points of Presence (POPs) supporting 56K, there is nothing else you need to do.  If your ISP has upgraded to V.90 and you want the universal interoperability that V.90 offers, then check with your modem manufacturer to get the upgrade details.


What can the MTU settings do for my Internet connection?

Here's a simple analogy. TCP/IP takes a web page and cuts it into nice neat squares (packets). It puts each piece in an envelope with the address (header) of where it’s going for the routers to send it along its way.  Then all the letters are delivered to your mailbox. So:

MSS = the size of each cut square of paper

MTU = the size of the envelope (which must be slightly bigger than the square of paper)

RWIN = the size of the mailbox which "receives" the letters

The maximum speed of TCP/IP transfers through a SLIP (Serial Line Protocol) or PPP (Point To Point Protocol) connection is, first and foremost, limited by the speed of the modem.  In an ideal world, for an already compressed file, you should be able to get 3.2 Kbytes/sec transfers with a 28.8 Kbps (kilobits per second) connection; 2.7 Kbytes/sec with a 24 Kbps connection; 1.6 Kbytes/sec with a 14.4 Kbps connection; etc.  Roughly speaking, each one Byte/sec of delivered TCP data rate requires 9 bps of modem connect rate.  The data transfer speeds mentioned are the ideal speeds one can achieve, but this is often thwarted by fragmentation which may occur in the transmission of packets of data.

As you visit various web sites, you will encounter at least one router on the download path with an IP default MTU of only 576 bytes.  This is the most common MTU setting in use and is generally referred to as the "Internet Standard".  If you are using the Windows 95 default MTU setting of 1500, this will likely result in packet fragmentation slowdown (since you are trying to use TCP segments (MSS) larger than 536 bytes.)  Avoiding fragmentation has a major effect on file download speed, whether we are talking about html and image files from the web or straight text data bits in your e-mail program.


What is MTU?

MaxMTU Explained:

Data on the Internet is sent in chunks called packets.  The Internet standard packet size is 576 bytes (including 40 bytes for address information).  This packet size is known as the Maximum Transmission Unit, or MTU.  The 536 bytes of data remaining after the address information is subtracted are known as the Maximum Segment Size (MSS).

The problem is that the default setting for Windows 95 Dial-Up Networking is an MTU of 1,500 bytes. This setting is ok for Internet connections made through a LAN. But since most consumers use a dial-up connection (via modem) it tends to slow down the download time while it resends the packets to accommodate the mismatched packet size.

MTU is usually set in conjunction with MSS, the Maximum Segment Size, and RWIN, the TCP Receive WINdow. MSS is the largest segment of TCP data that the Winsock is prepared to receive on that connection. MSS must be smaller than MTU by at least 40 bytes, the size of the header and trailer information. The tool will automatically adjust MSS when the user changes MTU. RWIN determines how much data the receiving computer is prepared to receive. If RWIN is set too large it will result in greater loss of data if a packet is lost or damaged. If it is set too small (e.g. 1x MSS), transmission will be very slow. Normally RWIN is set to either 4x, 6x or 8x the MSS value which is 40 bytes less the MTU.

Adjusting the MaxMTU:

The Manual Tune-Up provides access to the MTU adjustment.  When the program is first run the MTU value will be grayed. If the user used a third party program to adjust this value the currently selected value will be displayed. If the value set matches 576 or 1500 then that button will also be highlighted. The user can adjust to any value they wish by pressing the top (to increase) or bottom (to decrease) of the round button. The user must press the "Apply" button to set the new value.

Common MaxMTU values:

The following are values you can experiment with when adjusting the MTU value manually:

400, 512, 552, 556, 576, 1000, 1006, 1024, 1152, 1500


What is RWIN?

RWIN Explained:

The RWIN setting determines how much data the receiving computer is prepared to receive.  While significant improvement in transfer rates have been achieved with only the MTU setting, for maximum efficiency and even better results can be achieved with different settings for RWIN.  First try only the MTU setting change only and check the results. The performance can even be better after making the RWIN settings changes as well. There have been reports that the MTU change produced good results which were then negated by making the RWIN change as well as reports that were only good after they changed both!

If RWIN is set too large, it can result in a greater loss of data if a packet is lost or damaged. If RWIN is set larger than your ISP's value, it can cause "framing errors". RWIN is set to a whole integer multiple of MSS (MTU - 40). The default value for RWIN under Windows 95 is 8192 which is then rounded up to the nearest MSS increment for the connection.  Using an MTU setting of 576 would appear to create a TCP Receive Window much too large for the 576 setting.

Adjusting the RWIN:

The value of RWIN = 4x MSS (remember, the MSS value is the MTU value minus 40) is a good choice to start with.  You can also experiment with 6x, 8x  and 10x settings. Some cable modems use extremely high RWIN settings without having an MTU value present but these values vary greatly between providers. You can select which RWIN value they want by pressing the buttons under the MTU adjustment button. You can also set a custom value by clicking on the RWIN title button. You must press APPLY to accept the new value.

Common RWIN values:

For most analog connections, values of 2x, 4x, 6x, 8x and 10x are recommended.


What is TTL?

Time To Live (TTL):

Time To Live is a field in the IP header which indicates how long a packet should be allowed to survive before it is discarded. TTL essentially determines the maximum number of hops permitted before giving up. The default is 32, but with the Internet growing all the time, it is recommended setting it to the larger value of 64. Manual Tune-Up will permit the user to select which value they want to use.

Common TTL values:

There are a finite set of values for TTL: 32, 64, 128 and 255. If you are using the DUN 1.2b update available from Microsoft, a TTL value of 128 is recommended.


What is PMTU?

PMTU:

Path of Maximum Transmission Unit has two features; Discovery, which finds a path that will allow the transmission of the MTU packet without fragmentation, and BlackHole Detect which is suppose to detect MTU routers that do not return ICMP messages.

Discovery:

PMTU Discovery is used to automatically determine an effective path for sending by determining the largest size MTU that does not require fragmentation anywhere along the path from the source to the destination. In theory when the MTU is set at the Windows 95 default of 1500, the Discovery PMTU should negate the MTU problems mentioned earlier, but the reality is that it take more time to negotiate when a large number of hops are involved, often far outweighing any practical advantage.  If PMTU Discovery is disabled, it causes an MTU of 576 bytes to be used for all connections that are not to machines on the local subnet.  Microsoft specifically warns that disabling PMTU Discovery can cause a serious degradation in performance, but there are always certain circumstances where this may not be true.

PMTU Discovery Values:

PMTU Discovery is enabled by default in Windows 95. You can enable or disable this value.

BlackHole Detect:

PMTU BlackHole Detect specifies whether TCP will attempt to detect MTU routers that do not send back ICMP (Internet Control Message Protocol) fragmentation-needed messages. With BlackHole Detect enabled, TCP will try to send segments without the Don't Fragment bit set if several re-transmissions of a segment go unacknowledged.  If the segment is acknowledged as a result, the MTU will be decreased and the Don't Fragment bit will be set in future packets on the connection.  Enabling black hole detection increases the maximum number of re-transmissions performed for a given segment.  Setting this parameter when it is not needed can also cause performance degradation.  However, if the router is not sending back the ICMP messages, then PMTU Discovery will not work and can cause an even greater loss of performance, so it may be useful in certain specific situations.

PMTU BlackHole Detect Values:

PMTU BlackHole Detect is disabled by default in Windows 95. You can enable or disable this value.


Why does it say that I'm connected at 115,200 bps?

Sometimes the connect speed reported by your dial-up connection (the DCE) will be mistakenly reported as the DTE value. In other words, your 33,600bps connection might be mistakenly reported as a 115,200bps connection. Check your modem's users manual or web site for information on AT commands that can correct this mistake.


Why don't I get a dial tone when attempting to dial?

There are many different reasons you may not hear a dial tone when attempting to dial out. Here are some ideas to try:

•	If your modem has both a 'LINE' and 'PHONE' jack, be sure the telephone line extending from the wall goes into the 'LINE' jack.

•	Make sure that the wire from the wall phone jack is connected to the modem.

•	Connect a telephone to the line and listen for the dial tone.

•	Try changing the wire with another phone wire.

If none of these suggestions work, your modem may have been damaged. The 'No Dial' tone symptom is often the result of a voltage surge that came down the telephone line, especially if the modem used to work on that line.  This is common problem due to thunder storm activity.  Please contact your modem vendor’s technical support for assistance.


Why did Windows 95 disable my modem?

The most common reason Windows 95 would disable your modem is because of a resource conflict.

The resource assigned to the modem is probably the same as another device and there are if there are no available system resources you will have to free one up. To accomplish this it may be necessary to disable a device. Refer to your PC documentation for instructions on disabling the internal COM port (if it is not being used).

Valid COM Ports are: 1, 2, 3, and 4.

Valid IRQ’s are 3, 4, 5, 7, and 9.

One suggestion is to refer to your modem documentation for instructions on setting the modem to an alternative resource setting.

You can also check the mouse and determine if it a PS/2 or serial mouse. If it is a PS/2 mouse it may be possible to disable the internal COM port and free that resource for the modem.


Why can't I login to the Internet?

What happens when you can't log onto the Internet when you could before? Check the following and try dialing again:

1.	Verify your dial-up information. If you have recently created or recreated a dial-up profile, make sure the information you entered corresponds with the information you received from your ISP.

2.	Verify your user name and password. If you have the "remember password" box checked, this probably isn't the case, especially if you were able to use this connection prior to the problem. But if you enter your password each time you connect, make sure that the Caps Lock key isn't active, re-enter both your user name and password (remember, some passwords are case sensitive) and try again.

3.	Check the phone number you're using. Sometimes the access number for you ISP can change or get disabled without you knowing about it. Contact your ISP and verify that the access number you are using is still active and working.


Why can't I find Dial-Up Networking on my system?

Windows 95 does not automatically include Dial-Up Networking during installation. You can verify and if needed, install Dial-Up Networking using these instructions:

1.	Click on "Start", click on Settings, click on Control Panel

2.	Double click on the "Add/Remove Programs" icon

3.	Click on the tab labeled "Windows Setup"

4.	In the list of components, highlight "Communications"

5.	Click on the "Details" button

6.	Verify that the "Dial-Up Networking" component is selected. If it is not, select it now.

7.	Click on Ok until you are back at the Control Panel. You will probably be prompted to enter your Windows 95 CD-ROM or provide the location of the Windows 95 installation files and might also have to restart your system.

8.	Once installation is completed, double click on the "My Computer" icon on the desktop

9.	You will see a "Dial-Up Networking" folder. Double clicking on this will allow you to create a dial-up profile.