Connection Problems

 

There are a large number of causes for connection problem. Likewise the symptoms can vary significantly between different connection attempts. Connection problems can manifest themselves as a connection that never really gets established properly. The system looks like it is connected, but when you try to get mail, access the internet etc. you get an error message. Likewise, connection problems can occur when the connection comes up and works but then you get disconnected.

Connection problems can be very inconsistent. You may make 20 connections where no problems exist and then the next 10 have problems and you can't stay up long enough to read e-mail. Then it may work fine for the next few days.

Identifying the cause of connection problems requires systematic investigative procedures. There is no simple approach that will find anything but the simplest of configuration errors. Finding the cause of the problem may take considerable time and effort and then getting it resolved will take time. There is no magic, you need to be systematic and check everything out - even when you know that is not the problem. Keep detailed records. Frequently its the insignificant message from the machine that yields the clue when seen in combination with other "useless" information.

The approach I am outlining below covers a lot of various problems that we have encountered with LAFN user's systems. Some of it won't seem relevant and may not be. However, if you have collected all the information you may find the answer there or at least you will have the information available for our mentors and save several days of them asking you to generate it.

 

Causes

Connection problems can be caused by configuration errors in the PPP, TCP/IP, modem, browser, or mail programs. In addition, there are possible modem compatibility issues and even line problems.

Configuration problems will prevent some portion of the system from working properly. They can affect any portion of the system. It is even possible to misconfigure multiple portions of the system.

There continue to be many problems with the interpretation of the V.90 modem specification by various modem manufacturers. As a result not all V.90 modems work the same way. Some modem combinations just don't work properly. In order to provide 56Kb service LAFN has to use digital modems. The maker of these modems is trying to keep up with all the makers of the analog modems used by our users. Its a difficult proposition at best since those vendors are constantly updating their modem code.

Some modem compatibility issues can be resolved by a configuration change on the user's computer. Some will require waiting for the manufacturers to resolve them - or obtaining a new modem.

Line problems can also affect your connections. Noise on the line can cause various problems. In addition, your local central office may not have the bandwidth available to connect to LAFN. These problems will look like configuration errors many times.

One interesting aspect of the dial-in service is that there seems to be a problem with disconnects when you first start using the service. After a few days, for some users, the problems begin to go away and eventually you rarely encounter disconnects. I know of no explanation for this behavior. It has been observed by several users. Using the service for a week or so may result in significantly different performance.

 

Gathering the Data

The first step in resolving connection problems is to gather data. We start with the lowest level of the connection and work our way up. The higher level rely on the proper operation of the lower levels so we need to be sure they are working properly first. I will show how to gather the data for some of the various machine/OS/client combinations but I don't have access to all of them to be able to provide comprehensive instructions for all combinations. In addition, different versions of the same client may use different names for the icons, or menus. Sometimes things get moved around. The information will be there, you may have to be a bit creative in finding it.

 

Is it a Connection Issue?

There are two basic types of problems encountered by our users: connection issues and modem compatability issues. We need to first determine which type of issue is involved as the approach for resolution is different for each. If you are unable to make a connection then you need to first try a different number. Find a second local number for your area and try it. If the behavior is different between the different numbers, then this is a connection issue. For the number that does not work, try calling it on a phone. Do you hear the modem tones, or get an operator message. If you don't hear a modem tones, its a connection issue. If you get an error message when connecting, then its a connection issue.

For connection issues, you need to notify ops@lafn.org. Please include your user id, the number you are calling from, the number you are calling, the results of all the tests above. Please include all possible information such as the text of any error messages, not just a number. If another number worked, include that number also.

If its not a connection issue then you need to continue on and check the configuration and finall check for modem compatability issues.

 

Checking PPP Configuration

(This section is incomplete at this time)

The PPP connection from your computer to our servers is the lowest level. The configuration of PPP enables it to dial our servers and establish the basic connection. The key elements in PPP are the phone number to call, the user id, the password, and the various services to be handled. The Frequently Asked Questions section on the LAFN web page contains screen shots of the PPP configuration for the common setups. Check there first to be sure you are setup properly.

Macintosh MacPPP

Open the ConfigPPP Control Panel. Select the Config... Button. Check the port speed. Older Macs should be set around 38.4K Newer ones can be 56K. The Modem Init box is the modem initialization string that is unique for each different modem. Make sure that flow control is set to CTS and RTS.

Press the Authentication Button. Enter your user id (e.g., bc979). Do not enter your mail address (e.g., bc979@lafn.org). Likewise your password should be entered.

 

Macintosh OT/PPP

The current Macintosh PPP is officially named "Open Transport PPP" although it is most frequently noted as "Remote Accesss PPP". They are the same thing. Open the Modem Control Panel. Make sure that Connect Via indicates the proper modem. Be sure the Setup Modem is the proper type for your modem. The initialization string is in the type script. If its wrong the modem will not connect properly and can cause any of the symptoms described above

Open the PPP Control Panel.

 

Checking Mail Configuration

Some mail programs have a configuration item that if set will cause the mail program to disconnect from LAFN after reading or sending mail. Since one of the first things users do is check mail, this will look like a modem problem. In particular Outlook Express has this capability and occasionally it gets enabled without any user intention. Check and make sure its not set to disconnect after checking or sending mail. For Eudora, its in the Internet Dialup Settings. For Outlook Express, go to Tools, Options and select the Connection tab.

 

Checking Connection Operation

Please note that at this time our dial-in service has blocked the use of ICMP which means ping and traceroute will not work. You will need to skip the steps below which use ping.

Checking a connection requires the ability to ping. For Windows 95/98 users, you can go to the MS-DOS prompt and enter the commands there. Mac users should obtain Mac TCPWatcher from one of the shareware archives.

The first step is to determine if you have a working IP connection to LAFN. Ping 108.92.93.123. You should get responses with response times if IP is working properly. If you do not get a response then either the connection is not functioning or there is a IP configuration problem. Restart the connection and try again. If the problem remains, then check the TCP/IP configuration.

The next step is to determine if you can access the DNS servers. Ping zook.lafn.org. You should get a response with response times if DNS is configured properly. If you do not get a response then DNS is not functioning properly. Check the DNS configuration. Please note that on Windows 95 the Obtain DNS address from the Server is supposed to work, we have encountered situations where it will not work and the DNS addresses have to be entered manually.

Once you have the connection working properly, then the issue becomes will it continue to work for extended sessions. A properly configured machine should be able to run a full hour session without disconnects. However, do note that telco line conditions sometimes change thus causing a disconnection. These situations appear to occur for a period of several days and then go away. Therefore you have to monitor disconnections over a period of several weeks to get an accurate picture of connection reliability. Line noise problems are also affected by rain so changes in whether need to be considered.

LAFN does disconnect you if your connection is idle for 15 minutes. A connection is not idle if there is traffic being sent on the line. If you download your mail and then read it for 15 minutes, you will likely be disconnected because of the idle timeout. There was no traffic on the line even though you were busy. If you are being disconnected frequently over a several week period then you are probably experiencing modem compatability issues.

 

Then why won't my connection stay up?

There are several potential reasons for a few people who continue to experience problems maintaining a connection. One of them is line noise on the line from your home to the central office. If the connection problems are very intermittent, the time between the establishment of the connection and when you get disconnected does not have a pattern, then this is likely to be the cause

On the other hand, if there is a consistent pattern, connections only last 3 minutes, then the problem is most likely to be with the modem configurations. Not all modems interface well together with their factory default settings. For example, there are three different 56K modem designs. We have all V.90 modems. The original 56K modems prior to the V.90 standard will have problems connecting with us. Supposedly, they are all upgradable to the new V.90 standard. If your modem is pre-V.90, you need to contact the manufacturer's web site and find out how to upgrade it.

There are people experiencing problems with older modems (slower than 56K). Modems have a large number of configuration commands that are used to define how the modem communicates with its peer. Not all modem manufacturers use the same factory defaults. Hence, sometimes you will need to change the modem initialization string to achieve reliable performance. This can also occur with the 56Kmodems. Please note, you may be able to connect to one brand of modem using the defaults without any problems, but have consistent problems with another peer modem brand.

 

Check some simple items first

Please note LAFN uses V.90. While our modems will answer to K56flex, their support of that protocol is limited and probably will not give top performance.

 

See if there is an update available for your modem

Go to the web site of the modem manufacturer and check for updates to the modem flash code, the drivers, or the initialization strings. Update to the most recent of each of them for your modem and computer. Note, drivers are only needed for Windows 95/98. You will need the modem model name and number to navigate to the proper place on the manufacturer's web pages. There are some pages that list information for multiple modems. http://www.56k.com/links/Firmware_Updates/ provides information on firmware updates for many modems. http://www.56k.com/inits/ provides information on initialization strings and drivers.

Another thing to try is to add 2 commas "," at the end of the phone number. This delays the modem so that it does not hear some of the new protocol negotiations. This occasionally helps the older modems that would otherwise be confused by the new protocols. You can increase the number of commas up to about 6. Generally adding more will eventually prevent the modem from responding to the other end.

 

Check the Modem Initialization

There is a modem initialization string that is used when a connection is started to set various modem parameters. These parameters can directly affect modem performance. One place to start searching for initialization (init) strings for your modem is http://www.modemhelp.org where there is a lot of modem related information. You do need to be sure that the modem is being set to V.90 and not K56flex or X2. Sometime, reducing the speed may make the connections more reliable.

 

How to test your modem and line

There is a free bandwidth test available at http://webservices.cnet.com/bandwidth/ which will provide a quick check of the bandwidth of your connection. Please note this check will frequently give slightly different numbers each time you run it.

The following URL provides the instructions on how to dial into a line test number that will talk to your modem and measure the modem and the line to your central office. This is quite a good diagnostic tool. However, it is not a local call. It is a long distance call and will cost. If you elect to use it, read through the instructions carefully so that you don't spend lots of time figuring out what to do while connected. It requires some planning before hand.

http://www.usr.com/products/line-test.asp

Please note, the test above is not always available and is not guaranteed to show you can connect at that speed with LAFN. Since you are connecting via a long distance path from your central office, the performance when connected to LAFN may not be the same. Generally it is, but it is not guaranteed. The best way to check the path to LAFN is to use a modem that is known to work with LAFN and try it from your location.

 

What should I do now?

If none of the above has helped and you are still experiencing disconnects, then you need to print the following instructions, and use a terminal emulator that can talk to your modem to gather configuration information and send it to ops@lafn.org so that we can provide it to Lucent and get some assistance.

The first item required is the manufacturer, and model number of the modem. That may be difficult if its a laptop internal modem, but provide the best info you can. Don't open up laptops - the info most likely won't be on the card anyway.

The following requires a terminal emulator. On Windows 95/98 there is a terminal emulator named hyperterminal. On a Macintosh there are a number of terminal emulators: zterm, and kermit. Claris Works also has a terminal emulator. Setup your terminal emulator to save the input and output to a disk file. Then, using a terminal emulator, enter the following commands at the OK prompt: (note, not all commands will work on all modems - don't be concerned if you get an error message)

 

AT&V (This should display the modem configuration registers. Some modems use a different command. If this command does not yield several lines of numbers, see if your modem uses a different command and enter it).

The following commands have 3 letters A T I followed by a number.

ATI0 (The output of the ATI0 command is a 3-digit ASCII string)

ATI1

ATI2

ATI3 (the firmware version in numerical format)

ATI4

ATI5

ATI6 (hardware information on some modems and link diagnostics on others)

ATI7

 

Save the output and e-mail it with the modem manufacturer and model number to ops@lafn.org. Also include your user id, the number you are calling from, the number you are calling, results of the testing above, and any error messages (complete detail) you get while trying to connect or when disconnected.