Trumpet Winsock 3.0 - Frequently Asked Questions

1. How do I install it?

   1. Once you have downloaded, run the file 'twsk30d.exe' by double clicking on it to extract the installation files. When this is complete you will now need to start the installation process. To do this double click on the 'install.exe' file.

   2. Once the installation process has started, follow through each screen. Ensure that you choose to rename other winsock.dll and wsock32.dll files and save the changes to your 'autoexec.bat' file. If you do not make these choices then your applications will not be able to find your Internet connection which is established by the Trumpet Winsock.

   Note: If you are using Windows 3.11 and running Win32s then rename the Trumpet wsock32.dll file to wsock32.old and rename the Win32s wsock32.old to wsock32.dll.

2. How does the layer work?

   This release is not a full 32-bit version of Trumpet Winsock. Rather it contains a layer that allows 32-bit applications to utilize the 16-bit Trumpet Winsock under Windows 3.11 using Win32s. The main parts of the Winsock, tcpman.exe (the dialler and interface) and winsock.dll (the core of the Trumpet Winsock), have hardly changed since the Windows 3.x version. When a 32-bit application requires the Winsock, it loads wsock32.dll that in turn loads twsk16.dll. Most functions are passed directly through to the winsock.dll. The exceptions are the getXbyY routines, and the WSAAsyncGetXbyY routines. Since special Windows 95 classes are used to create a layer between 32-bit applications and the 16-bit Winsock, it will not work under Windows NT.

3. How do I login manually?

   1. From the 'Dialler' menu, select 'Manual Login'.
      You will now be able to send commands (as described in your modem's manual) to your modem using the "at" commands.

   2. Confirm that your modem is ready by typing an appropriate command (or initialization string), such as: atz <Enter>
      Each character should appear on the screen as you type them. If no characters appear on the screen, make sure that:

      • The modem is turned on and plugged in.

      • The modem is set to echo commands as they are entered. To enable echoing, type the following command: ate1 <Enter>
      
      If the characters are appearing on the screen, but the <Enter> isn't being taken, try adjusting the baud rate. The baud rate can be set in the 'Dialler/Settings' screen, and should be one of 9600, 19200, 38400, 57600, 115200.
      The modem should return: OK

   3. Instruct the modem to start dialling, by typing: atdt <number> <Enter>
      Note: For pulse dialling type atdp <number> <Enter>.
      The modem should now dial into your service provider. If the line is busy you will need to repeat this step until you get a free line.

   4. Once connected to your provider's machine, you will usually be asked to enter your username and password. Type these and press <Enter> after each one.

   5. If and when you are given a choice, select either SLIP or PPP depending on whether you have SLIP or PPP selected in the File/Setup screen.
      Your screen should now start being filled with nonsense characters.

   6. Press <esc> to enable SLIP/PPP

   7. If you are using SLIP and your IP address is allocated dynamically (that is, a line has come up saying, :Your IP address is....") you will need to:

      • Select 'Setup' from the 'File' menu

      • Enter the address you've been given in the IP Address field.

      • Press OK to continue

      If you are using PPP, this will be done automatically.

   8. Your connection should now be established and ready to use.

   9. Once you have determined your login sequence, you can set up a login script to automate the process. See How do I edit/configure my login script? for more information on doing this.

4. How do I get demand loading to work?

   1. Ensure that your login.cmd and bye.cmd scripts are operating correctly and return "Script Completed". For assistance with this see "How do I edit/configure my login script?".

   2. Select Login/Logout on application Load/Unload from the Dialler/Settings menu option.

   3. Finally, the 'Online Status Detection' from the Dialler/Settings will need to be adjusted to suit. Depending on your modem, select one of:

      • DCD (RLSD) requires "&C1" in your modem init string

      • DSR requires "&S1" in your modem init string.

5. How do I change my login phone number?

   As long as you are using a login script that is based on the example script distributed with the Trumpet Winsock, you can edit your login phone number, username and password using the following method.

   1. Go to the Dialler/Profile menu.

   2. Enter or modify the entry the press OK.

6. How do I set the Trumpet Winsock to redial automatically?

   To configure the Trumpet Winsock to redial automatically:

   1. Select a method of Online Status Detection in the Trumpet Winsock's Dialler/Settings screen.
      The most reliable method is DCD (Data Carrier Detect), which requires the modem command &C1 to be set. As an alternative, DSR (Data Set Ready) can also be used, and requires &S1. The settings &C1 and &S1 are the defaults for most modems.

   2. Select Automatic redial when disconnected from the Dialler/Settings screen.

7. Why is the modem connecting at 2400?

   The most common cause of this problem has been non-standard comm drivers. A number of communications packages replace the standard Windows comm driver with their own driver to optimize performance.

   To find out what type of comm driver you have installed view the comm.drv line in the [boot] section of your system.ini file.

   Setting it to comm.drv=comm.drv will reset it to the standard Windows comm driver, as long as the original driver hasn't been over written.

8. How do I configure my login.cmd script?

   It is important that your login.cmd script is working smoothly and returning "script completed".

   If it returns "script aborted" your Winsock applications will not be able to connect you to the Internet. For example, Netscape will return "Unable to initialise network layer".

   To personalise your login.cmd file you need to:

   1. Open the Server Settings window by going to Dialler/Profile.

   2. Click on Server Settings.

   3. You need to set the prompts to correspond to the ones returned from your server. e.g., Username Prompt: Login:

   4. Once you have entered the correct prompts, click on OK.
      Note: If your server requires you to use PAP or CHAP to login then ensure that the Server Settings are ALL blank.

9. How do I switch between tone and pulse dialling?

   The command 'dt' instructs the modem to use tone dialling, while 'dp' represents pulse dialling. You should enter the appropriate command into your dial string in the Dialler/Profile menu under the Modem Settings.

10. How do I change the modem setup string?

    Enter the appropriate modem setup string (or our standard &f&c1&k3) into the 'init string' in Dialler/Profile under Modem Settings.

11. Can I setup the Trumpet Winsock for multiple Internet Service Providers?

    It is possible to configure the Trumpet Winsock for multiple Internet Service Providers (ISPs).

    By default, the Winsock stores all its settings in a file called 'trumpwsk.ini'. You can use the -inipath=<path> command line option to specify an alternate *.ini file.

    To do this:

    1. Create a program item for the Trumpet Winsock that will use the alternate *.ini file. An easy way to do this is by making a copy of your existing Trumpet Winsock Icon. (i.e., tcpman.exe), and then selecting Properties from the File menu and modifying the copy's command line. i.e., c:\winsock\tcpman.exe -inipath=c:\trumpet\inifile2.ini. By default, if no path command is given, then trumpwsk.ini is used.

    2. Start the new version of the Trumpet Winsock and:

       • Select File/Setup and modify the parameters as required (in particular DNS and Domain Suffix).

       • Select Dialler/Profile to update the phone number, username and password. (if you use a PAP login, then set username and password under File/PPP Options.)

       • Set the appropriate Server Settings under the Dialler/Profile menu.
         
         

12. How do I get bye.cmd to hangup my modem?

    The bye.cmd script that is currently supplied with the Trumpet Winsock includes two alternative methods of hanging up the modem. To switch between the options select either Hangup String or Hardware (DTR) hang-up in the Modem Settings in Dialler/Profile.

13. How do I optimise my MTU, RWIN and MSS?

    We recommend the following values as a starting point:

    	SLIP/PPP	Ethernet
    MTU	576	1500
    TCP RWIN	2048	4096
    TCP MSS	526	1024

    These are enhanced by following the guidelines below.

    MTU

    The Maximum Transmission Unit (MTU) of a network is the greatest amount of data that can be transferred in one physical frame on that network.

    Fragmentation will occur if a packet is sent across a network that has an MTU smaller than the packet's frame length. This will lead to lower performance as fragments need to be reassembled. A work around for this, would be to lower the Trumpet Winsock's MTU to match the minimum MTU of the intervening networks. Since it is virtually impossible to determine the minimum MTU of the intervening networks, trial and error is usually the best way to find out.

    As a starting point, try setting the MTU to the MTU of your network. For Ethernet, 1500 is the maximum, and is recommended. The unofficial MTU for SLIP servers is 1006.

    TCP RWIN

    The TCP Receive Window (TCP RWIN) determines how much data the receiving computer is prepared to receive. An RWIN set too large will result in greater loss of data if a packet is lost or damaged. An RWIN set too small (i.e., 1 x MSS) will be very slow, as each packet will have to be acknowledged before the next packet is sent. An RWIN of 2 x MSS causes problems with silly window avoidance.

    The RWIN should usually be set to exactly 3 or 4 times the size of the TCP MSS.

    TCP MSS

    The TCP Maximum Segment Size (MSS) defines the largest segment of TCP data that the Trumpet Winsock is prepared to receive on that connection. When a connection is established, the two ends agree to use the minimum of each end's advertised value.

    If the MSS is too low, the data/header ratio will be low. Alternatively, a large MSS will lead to large IP datagrams. These will fragment when travelling across networks with small MTU's thereby decreasing performance. For this reason, performance may sometimes be improved by dropping the value of your MTU.

    Because headers are typically 40 bytes, your MSS should always be at least 40 less that the MTU. As a rule, set the MSS to the greatest power of 2 that is at least 40 less than the MTU.

14. How do I configure PAP?

    Password Authentication Protocol (PAP) may be used if your server supports it. However, you should only use it if your Internet Service Provider has instructed you to. PAP is a special part of PPP that is used for login authentication.

    The PAP username and password should not be confused with the username and password used for a dial-up SLIP/PPP account.

    To use PAP you must select Use Password Authentication Protocol (PAP) in the File/PPP Options screen, and enter your PAP username and password in the appropriate fields. You should also ensure that your Server Settings (Dialler/Profile) are ALL blank.