VROC: Virtual Racers' Online Connection

Development Notes

Part 1 | Part 2

VROC is currently under development. We plan to add a number of additional features to make VROC more useful and more convenient. Here are some notes regarding VROC's current status and our future plans for it.

Browser

VROC's race list pages require Netscape 4.07 or higher to work properly. Originally we required 4.05, but that version lacks full support of Java 1.1, and we plan to discontinue support for versions earlier than 4.07 in the near future.

Earlier versions of Netscape lack critical Java functionality and will not function correctly with the VROC Java applet.

Differences in the security models used by Netscape and Microsoft require accommodations for each browser. To keep the workload down during the development phase, I'm only supporting Netscape. Support for Microsoft Internet Explorer may be added later.

Security

We are now using a Java applet signed with an electronic security certificate. You no longer need to activate Codebase Principals. If you have already turned on Codebase Principals, you might wish to turn them off.

Known Issues

Can't Join Races with [Join]

This section has been moved to VROC Troubleshooting.

Netscape Dies Slowly

When you visit a page, such as the VROC race list page, which has a Java applet on it, your browser starts a separate module for executing Java.

In older versions of Netscape (4.05 through 4.07), when you exit Netscape after starting Java, Netscape continues running in the background for a minute or so. If you view it in the Windows Close Program box (press Ctl-Alt-Delete) you will see it continue to run. Eventually it will show as not responding, and then a few seconds later it will disappear.

If you attempt to restart Netscape while it is still running in background, bad things happen, not the least of which are Netscape and/or Windows hanging. I've become very careful to check to make sure Netscape has terminated before I restart it.

This appears to be a bug in Netscape versions 4.0x, and preliminary tests of Netscape 4.5 suggest that it has been quashed in that version. For this reason, among others, we plan to discontinue support of Netscape versions prior to 4.5.

Chat Applet Can't Start

Sometimes the third-party chat applet presents only a blank window and shows a message in the status line, "Chat applet can't start". Usually returning to the VROC Main Page and then re-entering the chat window will restart the chat applet.

Loading a New Version of the VROC Applet

For some reason, once Netscape has loaded a particular applet, it refuses to reload it unless you stop and restart Netscape.

Therefore, if we install a new version of the applet, you'll have to stop and restart Netscape to get it. When you do, beware of the problem described under Netscape Dies Slowly, above.

Incorrect Local IP Address

If the VROC applet reports an incorrect IP address for your Internet connection, no one will be able to join races you host (although you will be able to join other peoples' races).

There are at least two reasons why the VROC Race List applet might display an incorrect IP address for your machine. There are workarounds for both problems.

Here is a discussion of the potential causes of these problems, and workarounds.

Reconnecting DUN while Browser is Running

If you're like most people who connect to the Internet through Dialup Networking (DUN), you have a have a dynamic IP address. A new IP address is assigned each time you connect to your ISP. This means that if you close your Dialup Networking connection to the Internet, and reconnect, you will now have a new IP address.

If you do this while Netscape is running, Netscape will not be aware of the change in your IP address, and will incorrectly report to the VROC applet the IP address which your machine had when Netscape started.

The solution is to remember to shut down Netscape and restart it if you disconnect from your ISP, and you plan to host a race through VROC.

Multihomed Machines

Machines with two IP addresses are known as "multihomed". If your machine is attached to a LAN and to the Internet, and you are running TCP/IP on the LAN, it is a multihomed machine.

If your machine is multihomed, Java may report your LAN IP address instead of your Dialup Networking (or other Internet) IP address.

As of VROC Beta 3f, the applet addresses this by retrieving a list of all IP addresses belonging to your machine. It ignores nonroutable IP addresses, including those in the ranges 192.168.*.* (most commonly used in home and other small LANs) and 10.*.*.*. and picks the other. If there are multiple routables, it takes the last one it finds.

If I hear enough cries of dismay, I'll make the applet ignore nonroutables in the range of 172.16.*.* through 172.31.*.*.

If, despite this, VROC is still reporting an incorrect IP address, you can enter the correct IP address in the IP Address Override field in VROC Setup.

Note: If you formerly used VROC Setup to override the IP address on a multihomed machine, you might like to delete the override and see if the applet now correctly reports your Internet IP address.

Null Pointer Exception

You might get a Null Pointer exception. I kept quashing this and it kept popping up again in the early days of development, but I don't see it very often these days. It appears to be due to a timing issue when initially painting the stuff on the applet.

Unless and until I nail this bug, you must stop and restart Netscape to make it go away. Sometimes it recurs a couple of times, but keep trying.

Status Line Messages

Keep an eye on status line messages (in the little window at the bottom of your browser window). Right now, this is the only way I can display what's going on inside the applet. Eventually, I plan to add popups which will be more noticeable and more informative.

Other Errors

If you see any other errors, please let Tech Support know.

Future

We have plans for a number of enhancements. See the VROC To Do list for details.

Continue to Part 2