*****************************************************************************
* IPX NETWORK FAQ *
* v2.0 *
*****************************************************************************
* DATE: 11/13/95 * *
* AUTHOR: Joshua Jackson (
[email protected]) *
* Performance Peripherals *
* 4168 Americana Dr. #204 *
* Cuyahoga Falls, Oh 44224 *
* (216) 922-3487 *
*****************************************************************************
------------
!!!NOTICE!!!
------------
Anyone who has been sending EMAIL to my former EMAIL addresses:
[email protected] -or-
[email protected]
should re-address it to
[email protected] My previous accounts are no
longer online.
----------------
ACKNOWLEDGEMENTS
----------------
Thanks Id for such a KICK ASS game!! DOOM is a registered trademark of iD
Software.
Hank Leukart for the "OFFICIAL" DOOM FAQ.
Matt Fell for the Unofficial DOOM Specs v1.3
References are made to the following programs, here is a list of the authors:
DEU 5.21 : Raphael Quintet,
Brendon J Wyber
DUE 5.21 GCC port: Per Allansson,
Per Kofod
IDBSP10 : Ron Rossbach
BSP11X, BSP11TC : Collin Reed
BSP11W : Collin Reed, Alex Korobka
VNB1050, WARMxx : Robert Fenske, Jr.
DOOM, DOOM II,
IPXSETUP : The Mighty Wizards of iD
HERETIC, HEXEN : Raven Software / iD Software
--------
CONTENTS
--------
=SECTION ONE= Introduction
[1-1] What is an IPX NETWORK?
[1-2] Distribution of this FAQ
[1-3] Disclaimer
=SECTION TWO= Setting up an IPX NETWORK for DOOM
[2-1] Required Hardware
[2-1-1] The LAN cards
[2-1-2] The interconnecting cables/T's/Terminators
[2-2] Required Software
[2-3] Purchasing your equipment
[2-4] Connecting the computers
=SECTION THREE= Playing the game
[3-1] Trouble Shooting
[3-2] Speeding up your game play (Notes for level builders)
[3-3] Recommended add on software
[3-3-1] IPXFER
[3-3-2] BSPCOMP
=SECTION FOUR= Technical Information
[4-1] DOOM's IPX communications
[4-2] The doomdata_t structure during game play
------------------------------------------------------------------------------
SECTION *1*: Introduction
------------------------------------------------------------------------------
[1-1]: What is an IPX NETWORK?
The term IPX (Internetwork Packet Exchange protocol) simply represents
an industry standard, developed by XEROX, for communicating between computers
in a Local Area Network (LAN), Mainframe, or the two computers that you have
sitting around your house.
In order to implement this you will need all of the required hardware
(detailed later), software, and the know how. Hopefully this FAQ will detail
most of this information so that you can be up and running in 2, 3, or 4
player games soon.
[1-2]: Distribution of the FAQ
This FAQ is intended for anyone and everyone that wants more information
or is having trouble setting up an IPX based network for DOOM. I would
appreciate it if no modified copies of the FAQ other those I release in the
future be distributed in any form.
NOTE: If you feel any of the information in this FAQ to be incorrect please
send me EMAIL or contact me in person to let me know. I will make a prompt
adjustment and re-release it.
[1-3]: DISCLAIMER
The author accepts no responsibility for any damage whether it be hardware,
software, or mental caused by the use of the information contained in this
FAQ. All the information presented is, to the best of my knowledge,
technically correct.
NOTE: I am not a certified network technician. All of the information in
this FAQ was obtained through personal experience. I have been working
with IPX based networks (mostly Novell) for the last six years and
have become quite familiar with both their inner and outer workings.
Therefor I do not claim that all of the information contained in this
document to be free of error, but it is working for me, so I hope it
works for you!
------------------------------------------------------------------------------
SECTION *2*: Setting up an IPX Network for DOOM
------------------------------------------------------------------------------
[2-1] Required Hardware
Contrary to popular belief, you do NOT need a full blown LAN to operate
IPX network DOOM. Since you simply need the LAN cards and your IPX drivers,
you can set up a network for DOOM for around $10,000 less than a server
based local area network.
[2-1-1] The LAN cards
The first piece of equipment you will need to set up your DOOM network
is a set of LAN cards. Whether they be Ethernet, ARCNET, or some other
off the wall type, they just need to be able to talk to one another. My
personal system is set up on a series of NE2000 compatible Ethernet cards.
Most all of my discussion will be based around NE2000 compatibles, since I
have had no trouble whatsoever with these cards. (Plus they are very fast
and inexpensive). When purchasing your LAN cards, it is recommended that
you purchase cards that support CO-AX cable hookups. CO-AX is cheaper,
easier to obtain and a better medium for network communications than
twisted pair.
[2-1-2] The interconnecting cables/T's/Terminators
Next is your cable hookups. The cable that I am using is standard
RG-58 CO-AX cable. This cable is inexpensive and VERY easy to obtain.
In order to hook your cables to the LAN cards, you will NEED a set of
BNC style T connectors.
>>>NOTICE<<<
YOU CAN NOT HOOK TWO CARDS DIRECTLY TOGETHER WITH THE CABLES AND
HAVE IT WORK!!! YOU WILL NEED A SET OF Ts AND TERMINATORS. THE
TERMINATORS ARE EXPLAINED IN THE NEXT PARAGRAPH.
Finally, you will need a set of 50ohm terminators. These terminators
are crucial to your network's operation. If you are not sure what I
mean by terminators, I will include a description of them and how to
build your own in the next section. Whether you are connecting 2, 3,
or 4 computers, you will need exactly 2 terminators.
[2-2] Purchasing your equipment
Purchasing all of this equipment is not as tricky or as expensive as you
might think. The LAN cards can be obtained either through me, the Computer
Shopper, or at most Computer shows. The rest of the equipment is available
at your local Radio Shack store.
If you would like to order LAN cards, you may do so through me (Jackson
Software) by contacting me at the following:
internet:
[email protected]
Snail : Joshua Jackson
Performance Peripherals
4168 Americana Dr. #204
Cuyahoga Falls, OH 44224
Phone : (216) 922-3487
For those of you wishing to setup a DOOM network, I am currently offering
you a deal that you won't find anywhere else: I am selling NE2000 compat.
Ethernet cards to anyone who wants them at my cost (wholesale) plus
shipping charges. Both software and hardware configured cards are
available starting at around $40.
The cabling and all of its accessories can be obtained pre-made through
me, or if you are a do-it-yourselfer, at you local Radio Shack.
If your cards do not already come with a BNC T connector on the back, the
Radio Shack Part# and current price is:
278-112 BNC T-Adapter $3.19 ea
(You will need one per network card)
Next are the terminators. The parts to make one of these from Radio Shack
are the following:
278-251 BNC male to F female $1.99 ea
(One per terminator - you will need two of them)
(BTW: F style is the same as used for cable TV connectors)
271-1311 5pack of 100ohm Resistors $.49 ea
(You will need two resistors per terminator and two terminators per
network - a total of 4 for those of you not up on your math skills :)
Building the Terminator:
Take two 100 ohm resistors and twist the end leads together so that
the resistors are in parallel (this will give you 50ohms)
here is a poor rendition of a text diagram
-----------[100]------------
leads `twist, `twist, leads
-----------[100]------------
once you have your 50 ohm resistor, you will need to insert one of the
twisted ends into the small hole on the F style end of the BNC to F
style adapter. The other end you will simply wrap around the threaded
outer casing of the adapter. To secure the resistors in place, you can
use tape, but I recommend either heat shrink tubing (Radio Shack Part
Number: 278-1627) or better yet Liquid Plastic (available at most
hardware stores).
Your terminator is now complete, on to the cables. As mentioned
earlier, the cable you will need is standard RG-58 cable. The Radio
Shack part number and price is:
278-1314 RG-58 Co-AX $.20 per foot.
The ends for the cables are:
278-103 $2.99 ea.
(You will need two per cable)
Building your cables:
First, I recommend that you either get some practice stripping CO-AX
or you buy yourself a set of CO-AX strippers. This is not the
easiest thing in the world to do!
1. Cut the cables to the desired length (Plus a couple of inches if
you have never attempted to strip CO-AX before)
2. Strip the CO-AX to the below specifications:
_________
_________}}}=------
| | | |
| | | `---> Inner solid copper wire 9/16"
| | `------> Dielectric (White plastic) 1/32"
| `--------> Shielding (Braided wire) 1/8" - 3/16"
`--------------> Outer casing
3. Twist the BNC end onto the stripped cable, making sure that the
inner wire fits into the VERY small hole up inside the center
of the connector.
4. Get excited, you are almost there! On to the next section.
[2-3] Required Software
The required software that will be needed to play your game as far as your
LAN card is concerned will come as three files:
LSL.COM
<A vendor specific driver> (Mine is NE2000.COM)
IPXODI.COM
Please do note: I have received several calls regarding an file called
IPX.COM that comes with a lot of the LAN cards out there. From my experience,
DOOM does NOT like these drivers unless you are attached to a fully server
based LAN. This file IPX.COM, integrates all of the three above drivers
into one itsy bitsy little file. If anyone out there has gotten DOOM to
run with MORE than 2 player while using this file and you are NOT on a full
Local Area Network, please write or call and let me know exactly what you
did you make this configuration functional.
It was brought to my attention that v1.0 of this FAQ did not mention anything
about the required NET.CFG that must accompany the above mentioned drivers.
When setting up your <vendor specific driver> and linking it (in memory) to
the DOSODI driver, you will need to either modify an existing NET.CFG or
create your own. This file tells the drivers what port address/IRQ your card
in on as well as what protocol frame to use. The following is my NET.CFG
file:
Link driver NE2000
Int 10
Port 300
Frame Ethernet_802.3
protocol ipx 0 Ethernet_802.3
The values for Int and Port are assumes to be in hexidecimal format. These
values MUST be modified to reflect the settings of your card. The first line
should contain the name of your vendor specific driver.
If you have difficulties getting the computers to connect once you have gotten
all the hardware and software setup, check the Frame and Protocol settings,
they must match on each computer.
NOTE FOR NON-IDE CD-ROM DRIVE OWNERS: Port address 0x300 is the factory default
for most CD-ROMs. If you have a CD-ROM and you are using it proprietary card,
make sure that your LAN card and CD-ROM aren't in conflict.
I also would reccomend creating a set of files that load your network drivers
and also unload them from memory. a followinf is a copy of my batch files
for doing so:
C:\NETWORK>type startnet.bat
@echo off
lsl
ne2000
ipxodi
C:\NETWORK>type stopnet.bat
@echo off
ipxodi -u
ne2000 -u
lsl -u
echo.
echo Network drivers have been unloaded.
=================
The final piece of required software is of course IPXSETUP.EXE. This file
is supplied with DOOM v1.2 or above. To get a two player game going with
no special options simply type:
IPXSETUP
on both computers. If you wish for more than two players in a network game,
you will have to specify the -NODES parameter when starting IPXSETUP.
eg: IPXSETUP -NODES 3
would start a three player game. A maximum of four players can be specified
for a network game of DOOM.
[2-4] Connecting the computers
Now the the grand finale- Putting it all together.
1. Install the LAN cards in an available slot in your computer. Refer to
the instruction manual provided with the card if you are unsure as how
to go about doing this. If you still have trouble, call your 8 year
old son/daughter into the room and have them do it! :)
2. Connect the BNC T connectors to the back of all the cards.
3. The two end computers (or both in a two player network) should have
one of their BNC T ends capped off with the BNC terminators that we
made earlier >> AGAIN I STRESS- THIS IS CRITICAL FOR PROPER NETWORK
OPERATION!!! <<
4. Connect the remaining BNC T ends with the cables that we made earlier.
Another poorly designed diagram:
< or > indicates a terminator
T indicates a BNC T
=== indicates the cabling
<T===============T==============T===============T>
----------- ----------- ----------- -----------
Computer #1 Computer #2 Computer #3 Computer #4
5. GO FOR IT!!!!
------------------------------------------------------------------------------
SECTION *3*: Playing the game
------------------------------------------------------------------------------
[3-1] Trouble Shooting
The following section is a Questions and Answers section of commonly asked
questions (hence the name FAQ I guess)
Q) Why can I only get two players working?
A) #1 Make sure that you are specifying the -NODES parameter for IPXSETUP.
#2 Make sure that all of the LAN cards that you are using speak the
same language (Ethernet 802.3, etc)
#3 Make sure all of your cabling is properly connected and there are no
shorts in it. (Some LAN cards WILL use a shorted cable as a terminator
hence causing you a lot of grief trying to figure out why the third
computer is not being recognized)
#4 This one is somewhat a mystery, but it does happen:
I have received several calls regarding an file called
IPX.COM that comes with a lot of the LAN cards out there. From my
experience, DOOM does NOT like these drivers unless you are
attached to a fully server based LAN. This file IPX.COM,
integrates all of the three above drivers mentioned in section 2-3
into one file. If anyone out there has gotten DOOM to run with
MORE than 2 player while using this file and you are NOT on a full
Local Area Network, please write or call and let me know exactly
what you did you make this configuration functional.
Q) Why can't I get any of the computers to talk to one another?
A) #1 Make sure that all of the LAN cards that you are using speak the
same language (Ethernet 802.3, etc)
#2 Make sure that the end computers have the Terminators attached to
the open ends of the BNC Ts!
#3 Check your cables for a dead cable.
Q) What is IPX NOT DETECTED?
A) ummm, go figure! (Load your drivers!)
Q) Why does IPXSETUP give me an "OPEN SOCKET 0xFF" after I abort an
IPXSETUP session?
A) The original IPXSETUP.EXE has a bug in it. It does not close the
communication channel that it opens if you abort it. The error 0xFF
if generated by the IPX driver if you try to open an already open
IPX socket (communications channel).
Q) Why is my network game play so slow?
A) #1 The speed of your network is limited to the following:
-The speed of the SLOWEST computer
-The speed of you network cards
-The number of active images on the level being played
#2 You are using a PWAD file that was either poorly created or
the PWAD file you are using was run through a poor NODES builder.
#3 Your cables are too long, the maximum length for a cable should be
580 ft. (That's one heck of a long cable!)
Q) Why won't my network drivers load?
A) #1 Check to make sure that you card is properly seated in its
expansion slot.
#2 Make sure that your NET.CFG reflects the actual settings of your
LAN card.
#3 If you own a CD-ROM, the factory default for a CD-ROM card is
usually 0x300, it is the same for LAN cards. Make sure you don't
have both of these devices on the same port address.
[3-2] Speeding up your game play (Notes for level builders)
The speed of your network game play is based on several things. The
most limiting factor in network game play is the speed of the slowest
computer. For instance even if you have 3 Pentium/90s and only one 386sx/33
running on a network, game play will be reduced to a crawl!
Second is the speed of the LAN cards that you are using. I do not recommend
that you use cheap 8bit cards, such as many of the ARCNET cards that you can
pick up at a local computer show for half the price of a good 16bit card!
Next, make sure that all of the cables and most importantly, the terminators
are properly connected and of the right values. Excessive packet collisions
can result, hence slowing down you game play.
Finally, a note for level builders:
The following is from my personal experience. If certain NODE builders are
used to compile the necessary BSP information in a PWAD file, it can very
seriously reduce the speed at which the game engine can generate images.
The following is my personal review as well as ratings and problems that I
encountered while developing my own PWAD levels:
NODE builders (Best - Worst)
Name Description/Problems
-------------------------------------------------------------------------
IDBSP1x.EXE A port of John Carmack's source for Id's NODE compiler.
Absolutely AWESOME! This is by far the best node builder
that I have run across. No problems to mention.
This program was written for GCC therefor is 32bit DOS extended
and does not have any memory problems
NODECOMP.EXE Well, of course this program gets a good rating, I wrote it. :)
It is based on several node builders that are out there. The
node calculations are based on a cross-breed of IDBSP and BSP12x.
It also has several options that can make game play a tad more
interesting... If you're curious, check it out. (BSPCOMP.ZIP)
BSP1x.EXE An excellent series of NODE builders! Before the above
mentioned programs can into existence, this was my node builder
of choice. Problems: does not calculate REJECT data therefor
some games can be slowed down, especially if there are a lot of
monsters lurking about.
WARMxx.EXE, Builds a glitch free set of nodes, but does so in such a fashion
VNBxx.EXE that they are not optimized for use with the DOOM game engine.
This will seriously slow down game play. If you have a faster
computer, you may never notice this, but on a 386, you will most
likely find that the games are a bit choppy when looking out
across large areas.
One great advantage to the WARM series of utilities is the
ability to do a great number of manipluation on the wad files
themselves. You can flip, rotate, merge, and otherwise greatly
alter the levels themselves with a series of command line
switches.
DEU's Well, I LOVE the editor, but their node builder still needs a
little bit of work. In some complex areas, it will give you
the Hall Of Mirrors effect.
Here is my personal setup for creating PWADs:
DEU521GCC The 32 bit extended port of DEU 5.21
IDBSP12/
BSPCOMP For recompiling the NODES and other related BSP information
[3-3] Recommended add-on software
This section has shrunk greatly since the last version of this FAQ,
I have not been keeping up with software development in the last
year for these games... Working WAY to much.
[3-3-1] IPXFER
file: IPXFER21.ZIP
I wrote this package of software for sending files back and forth
across an IPX network.
IPXFER is currently at version 2.10 and is available all over the
place, just do a search for IPXFER with your favorite FTP search
engine. I have even found this program (and some of its lesser
versions) burnt on many of the shareware CDs out there, so check
you local BBS's as well.
It is designed to eliminate the headache of flipping floppies when
you are swapping PWADS (wow, what a tongue twister). It will
transmit data at rates between 100k - 350k per sec, depending on the
speed of the slowest computer and the speed at which your computer
writes to the harddrive (a cache helps) It is also capable of
multiple file transfers (you can tell it to send *.*).
file: BSPCOMP.ZIP
A node compiler that I wrote that has a boat load of built in features
for manipulating a WAD file to put a twist on playing your favorite
levels. It can flip and expand the levels, plus includes a few
other nifty effects.
This node builder is based on several other node builders, I attempted
to duplicate some the better features os each. It is very fast
(for being written in Pascal) and extremely efficient. It can
rebuld the entire DOOM/DOOM2/HERETIC IWAD files in real mode...
the DPMI version (included in the ZIP) can handle any legit wad file
that you can throw at it.
------------------------------------------------------------------------------
SECTION *4*: Technical Information
------------------------------------------------------------------------------
This section is not very large at the moment, in future releases I plan
to expand on this section. This section is designed to aid those of you who
are attempting to write their own software that deals with the IPX
communications of DOOM. This section is geared toward those of you who
already have a background in IPX communcations programming.
[4-1] DOOM's IPX communications
The Official DOOM socket # 0x869C
If during your fumbling about with the DOOM IPX communications, you should
leave the socket open, the following little program will close it for you.
mov bx, 1
mov dx, 9C86h ;Socket #'s are in hi-lo format
int 7Ah
NOTE: IPXSETUP.EXE allows you to change the default socket for communications.
This is accomplished by specifying the -PORT parameter, followed by the
socket ID you wish for DOOM to use. IF you are in a server based
network, BE CAREFUL when you do this!!! The following sockets are
defined are reserved by XEROX:
1 Routing Information Packet
2 Echo protocol packet
3 Error Handler Packet
20h-3Fh Experimental
40h-BB8h Are registered as in use by XEROX
The following are used by Novell Netware:
451h File Service Packet
452h Service Advertising Packet
453h Routing Information Packet
455h NetBIOS Packet
456h Diagnostic Packet
Finally, the communications packets that are send by DOOM have the following
format:
During Setup, the following packet structure - Less the ECB, and IPX headers
typedef struct
{
short gameid;
short drone;
short nodesfound;
short nodeswanted;
} setupdata_t;
And during game play, it switches to the following structure (Including
headers)
typedef struct
{
char private[512];
} doomdata_t;
typedef struct
{
ECB ecb;
IPXPacket ipx;
long time;
doomdata_t data;
} packet_t;
[4-2] The doomdata_t structure during game play
Here are the pertinent defs:
typedef struct
{
char forwardmove;
char sidemove;
short angleturn;
short consistancy;
byte chatchar;
byte buttons;
} ticcmd_t
#define BT_ATTACK 1
#define BT_USE 2
#define BT_CHANGE 4 // if true, the next 3 bits hold weapon number
#define BT_WEAPONMASK (8+16+32)
#define BT_WEAPONSHIFT 3
#define BT_SPECIAL 128 // game events, not really buttons
#define BTS_SAVEMASK (4+8+16)
#define BTS_SAVESHIFT 2
#define BT_SPECIALMASK 3
#define BTS_PAUSE 1 // pause the game
#define BTS_SAVEGAME 2 // save the game at each console
// savegame numbers occupy the second
// byte of buttons
typedef struct
{
unsigned checksum;
byte retransmitfrom; // high bit is retransmit request
// only valid if NCMD_RETRANSMIT
byte starttic;
byte player, numtics;
ticcmd_t cmnds[BACKUPTICS];
} doomdata_t
int NetbufferSize (void)
{
return (int)&( ((doomdata_t *)0)->cmds[netbuffer->numtics]);
}
unsigned NetbufferChecksum (void)
{
unsigned c;
int i, l;
c = 0x1234567;
l = (NetbufferSize () - (int)&(((doomdata_t*)0)->retransmitfrom))/4;
for (i=0 ; i<l ; i++)
c += ((unsigned *)*netbuffer->retransmitfrom)[i] * (i + 1);
return c & NCMD_CHECKSUM;
}
If you are interested in IPX programming, there are MANY good books out there
on the topic.
