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DUN FAQ |
Yes they should do. The modem part is transparent to TCP/IP so the actual speed of the modem should have no effect on the best settings. This has been confirmed by myself and others when we changed from 33.6 to x2.
Winsock 2 is a further winsock upgrade not to be confused with the winsock upgrade you install with DUN 1.2. Some programs i.e. cybersitter97, are not compatible with this yet so it is not on my general list of suggested upgrades. Winsock 2 does have a good uninstall though and I have had some reports that it made an improvement. Note that if you have problems with this, that it backs up all the files it changes and makes a remove batch file in windows\ws2bakup. Running the batch file should restore everything. Windows 98 uses winsock 2 so upgrading to 98 may make it necessary to upgrade other programs as well (i.e cybersitter99).
The key to good game play must be to reduce the latency so the first set is to make sure the com port settings are as high as possible (which should already be case if you have followed the tips page). The next thing to try is a smaller MTU setting like 576 or 512. Modems re-send data when it is corrupted and switch speeds (retraining) to follow phone line performance, all of which takes time. So another step to try is to limit the maximum speed of the modem to a lower level than normal to ensure you get no re-sends or retrains. The codes depend on the modem type so you will have to look in the manual to see what you need. Go to Your DUN Properties, General Tab, Configure Button, Connection Tab, Advanced Button and enter the code in the extra settings box.
Other things that may help is to disable modem compression. To do this go to Your DUN Properties, General Tab, Configure Button, Connection Tab, Advanced Button and untick 'Use error control'. The reasoning behind this is that the modem buffers the data so it can compress it by looking for repetition, the same way any compression works. The last thing you want is for the modem to hang onto to your data. This step, depending on the internals of the modem may not stop it from buffering of course. You final and risky step is to turn off error correction but if you do get a corruption you may crash the game so treat this a the very last resort. At the same time you should reduce the maximum speed for modem to ensure a good connection.
You can find out the MTU of a route by using PING as follows
PING -L MaxMTU-28 -F -W 10000 destination-IP-address
The minus 28 is for the header information (IP and ICMP). If this packet size gives fragmentation errors, decrease the value until the packet is echoed without fragmentation. An MTU of 1500 (ping 1472) is the windows default value. The -f parameter sets the Don't Fragment Flag in the IP header, and -w ensures that ping waits for a reasonable amount of time for the echo packet to return.
For example if I wanted to check that my MTU was 576 I would use 548 bytes as that is 576-28 and I would ping my ISP's news server and see the following:
C:\WINDOWS>ping -l 548 -f -w 10000 news.dial.pipex.com
Pinging plug.news.pipex.net [158.43.192.23] with 548 bytes of data:
Reply from 158.43.192.23: bytes=548 time=367ms TTL=251
Reply from 158.43.192.23: bytes=548 time=275ms TTL=251
Reply from 158.43.192.23: bytes=548 time=280ms TTL=251
Reply from 158.43.192.23: bytes=548 time=265ms TTL=251From this I know that MTU is at least 576 so I would then check 577 and see:
C:\WINDOWS>ping -l 549 -f -w 10000 news.dial.pipex.com
Pinging plug.news.pipex.net [158.43.192.23] with 549 bytes of data:
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.Both of these examples are copied from real tests.
As you can see by trying different values you can work out what MTU is being used. But it could be your MaxMTU setting that is the limiting factor so don't forget to set MaxMTU to 1500 or more before using this method to find your ISP's MaxMTU. Also, if you have Internet Connection Sharing installed and enabled the figure will be 4 bytes lower, so a MaxMTU of 1500 will go to 1468 before fragmentation not 1472.
Yes! For those of you with winmodem, which now includes me, you might find problems installing their software, I know I DID!. The secret is that after windows detects the modem and you have pointed it towards the directory with the files and it seems to have finished it asks to reboot. SAY NO. It will then go on and install the second part after which you can reboot. If you allow it to reboot at the first ask when it restarts it complains that winmodem isn't installed and offers to remove the files. I went round this loop three boring times before I worked my way through the inf file and discovered what the problem was.
You are confusing bits with bytes. 33600 is in bits where as 3.5k/s is in bytes, kilobytes in fact (1024 or sometimes 1000). So 33600 is raw 4200 bytes but there is also a few overheads. Modem to modem there are error checking bits and data framing bits which lose 4.97%. Then there is the TCP/IP header (packet number etc) overhead. This is usually taken as 40 bytes but of course with header compression enabled it should be less most times. Hence with a MTU of 576 the TCP/IP overhead is 6.9% and with a MTU of 1500 the overhead is 2.7% which shows why larger packets can be helpful.
The easiest way to do this is to use a program called ERU which you can find on the Windows CD. This not only makes a backup of the registry but also other useful files like config.sys. The manual way is to copy two hidden files in the windows called user.dat and system.dat. These are your registry. On Windows 98 you can use scanregw which will check the registry and then offer you the option of creating a backup.
This applies to Windows 95 as Windows 98 does not (yet :-)) have the same range of updates. Windows 98 is the equivalent of winsock 2 and DUN 1.3.
Go to control panel, network. Select Dial-Up Adapter and click properties. Select the advanced tab. If you have an IP Packet Size property then you have DUN 1.3. Otherwise go to control panel, add/remove programs and select the windows setup tab. Select communications and click the details button. Do you have an option for vitual private network? If you do then you have DUN 1.2 (or 1.3) as vpn only came out with DUN 1.2. If not then open system monitor and check to see if you have a category Dial-Up Adaptor with a load of entries e.g. CRC errors, Frame errors. If so then you have DUN 1.1 as these only came out with DUN 1.1. If not then you must have DUN 1.0. If you don't have system monitor go to control panel, add/remove programs and select the windows setup tab. Select accessories and click the details button. You will find it it this list.
The Navas Modem FAQ has information on this so I won't repeat it here. But it is a way of getting information out of the modem on the connect speed at the end, the number of line errors (called bler), bytes sent and received etc. More detailed information can be found at 56k Modem Troubleshooting page.
The commonest mistake is to enable file and printer sharing for your DUN as well as your home network. Check in Control Panel, Network, TCP/IP->Dial Up Adapter, Properties, that it is not bound to file and print sharing (untick the box under the bindings tab). An excellent site to check out your security with much more information is the Shields Up page at the Gibson Research Corporation site by Steve Gibson. This will tell you on-line what information can be obtained off your PC.
Windows 98 SE has the ability to sahre a internet connection amonst other PCs on a LAN. If fact as ICS does NAT (address translation) it makes a firewall between the PC and the internet and so is useful on PCs not on a LAN. However ICS will always dial out when another PC on the LAN requests access. As this PC is likely to be some distance from the dialling PC the user won't here the modem and thus be unaware he is hogging the phone (at least that is how it seems to work in my house :-(). ICS is meant to have a registry setting to disable auto-dial but it my experience it is not reliable. The solution is to set internet options to never dial. Now entering a URL in a browser even on the PC with the modem will not dial out. However by manually starting a net connection by click an item in Dial-Up Networking (or using one of the many tray programs to do this) the browser will fetch the URL off the net.
Call Divert is useful if you are using a service like Online Call Manager to take your phone calls when online. However, on the UK system you have to dial a number before to enable it and another number after logging off. To automate this requires software so I have written LAN Dial (freeware). This sits it the tray and when you click it a popup enables you to dial or hang up. Before it dials it uses the modem to dial the divert number you set and after it dials the cancel number you set.
Online Call Manager is now in receivership, last I heard. BT users could look at BT's Net Chat. But this is just an overlay on top of Netmeeting and it will change your Netmeeting settings. Plus it does not work if you have a network (and the software is dire).
To go with LAN Dial, and the reason LAN Dial is called Lan Dial, I have also written LAN Message (freeware). As with Lan Dial this sits it the tray and when you click it a popup enables you to dial or hang up. Only this time LAN Message passes this as a command to LAN Dial. The icon shows the current state and the program also is a system messager, like winpopup.
PC-Cillin anti-virus software and CyberSitter kid protection software are some what incompatible. But there is a fix which neither company seem to want to tell you. The fix is to disable PC-Cillin's Web Trap. It is this that causes browsering to fail on a PC with both programs installed. This does lower your virus protection as you lose the ActiveX virus detection, however you can (and probably should) disable ActiveX in IE. With later PC-Cillin versions (V7.5) all that is necessary to turn Web Trap off is to untick the web options. In earlier versions (V6) this is not enough and you need to rename Webtrap.exe to Webtrap.ex- (stop PC-Cillin first of course, otherwise windows will complain the file is in use). PC-Cillin does not complain about this. My guess is that the earlier version always loaded Webtrap whether it was used or not. The later version is a bit more smart.
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