==============================================================================
			    RELEASE V1.41
			(Released March 18'th 1993)

Approximately 2000 people worldwide are now using KarlBridge!

Thanks for making the OSU KarlBridge such a success!

Doug Karl
==============================================================================

		 Cleanup your network with the KarlBridge

		This is the Latest KarlBridge Version 1.41

WHAT IS THE KarlBridge?

The KarlBridge is a program, that runs on a 286 or 386 clone. It provides
a unique and inexpensive 2 port Ethernet to Ethernet bridge that performs very
sophisticated high level protocol filtering. The bridge filters packets based
on ANY specified Ethernet protocol such as IP, XNS, DECNET, LAT, AppleTalk,
NetBEUI, Novell IPX, etc.

In addition it provides IP "firewall" protection by filtering IP packets based
upon IP address/network/subnet combinations and socket number. It will also
filter DECNET packets based upon DECNET address, Area, Object number and
Object name. And filter AppleTalk Phase 1 & 2 packets based upon file server
name, printer name, and/or Zone name. (Yes Novell SAP filtering is coming
in the next release).

	The free version of KarlBridge is available via
	anonymous ftp from:  128.146.1.7 /pub/kbridge

WHAT ELSE IS IT?

The KarlBridge is also a complete bridge box based upon the commercial
version of the KarlBridge code.  It comes with AUI & 10Base2 or AUI &
10BaseT connectors. It is a very nice small box, with a 386DX40, 2 SMC
Elite 16 Ethernet cards, special boot ROM, and Floppy drive or Flash ROM
card. It is fully tested and burnt in for added reliability with a 1 year
warranty. KarlNet Inc. is the main commercial supplier of the KarlBridge
hardware and software.  KarlNet Inc. sells the KarlBridge box for $1195.
Look for the product review in March 1993 issue of Personal Computer
magazine, pg 455, published in England, and the upcoming April 1993 issue
of IEEE Computer. KarlBridges are also manufactured and sold in the UK by
Sherwood Data Systems.

SOME EXAMPLES:

	You can use KarlBridge as a standard medium to high performance
	MAC layer Ethernet to Ethernet bridge with SNMP (MIB II, Ether MIB,
	Bridge MIB & SNMP MIB).

	You can configure a KarlBridge to restrict traffic from your public
	computer labs or dial-in-lines to subnets within your campus or
	corporate LAN, prohibiting unauthorized access to your LAN or the
	Internet (in conformance with RFC 1173).

	You can configure a KarlBridge to pass only IP traffic and use it to
	replace many of the functions that people use an IP router for; such
	as localizing non-IP traffic to within a room or workgroup.

	    Many folks have use this feature to bridge IP (only) between
	    several Novell LAN's. They did not want to load down their
	    Novell server with the burden of routing IP between interfaces.

	    The same concept has been used to bridge NetBUEI or LAT (only)
	    between two IP routed networks.

	You can configure KarlBridge to keep file and print servers (Apple,
	Novell, Banyan, and etc.) on the same network from interfering with
	each other.

Join thousands of people worldwide who are using the KarlBridge to solve
some of their networking nightmares. The KarlBridge is the most flexible,
inexpensive and easily configured bridge you have ever seen!

Get a copy, read the README file, run the configuration program on your
favorite PC, and let me know what you think.

Please send e-mail to kbridge@osu.edu with questions, comments, etc.

Doug Karl		  KarlNet Inc.         Sherwood Data Systems, Ltd.
Ohio State University	  (614) 263-5275       +44-(0)494 464 264
kbridge@osu.edu		  sales@KarlNet.com    sales@gbnet.com

============================ Quick Overview ==============================

What do I need if I want to build my own?

	1) 286, 386SX or 386DX clone (with no keyboard or monitor)
	2) Two SMC (formerly Western Digital) Elite 16 Ethernet cards 8013EPC
	3) KarlBridge software

How do I make it work?

	1) Obtain a good reliable clone
	2) Install the Ethernet cards
	3) Configure a floppy with the software, on your favorite PC
	4) Insert floppy in clone
	5) Connect clone to your network
	6) Power it up!

=============== How To Quickly Evaluate the OSU KarlBridge ==============

FTP and de-archive kbridge141.arc that contains the following files:

	kbconfig.exe - KarlBridge Configuration Program.
	kbridge.com  - Executable image of KarlBridge for WD/SMC Elite 8
		       or 16 boards with the WD83C690 chip.
	readme	     - An additional copy of this file.
	kbpaper.txt  - A paper that wrote about the KarlBridge.
	kbmanual.txt - An ASCII'ized version of the commercial manual
			(looks bad in ASCII but great in print).

Issue the following command on your PC:

    kbconfig -f kbridge.com

This will start up the bridge configuration program.  This program modifies
the actual bridge program file "kbridge.com". Several menus will appear with
instructions on the bottom of the screen. This will demonstrate the many
configuration possibilities.  NOTE: The term "Remote" in this program refers
to machines that are connected to the bridge's Port 0 (Ethernet Board I/O
address 280).  The term "Local" refers to machines that are connected to
the bridge's Port 1 (Ethernet Board I/O address 2A0).

====================== Questions and Answers ===========================

1) Don't all bridges filter?

Yes & No; All bridges filter based upon Ethernet source and destination
address.  Protocol filtering bridges like the KarlBridge not only
filter based upon Ethernet address but also based upon the protocol that
is being passed. This allows greater flexibility in filtering out specific
protocols. In addition the KarlBridge also filters out IP, DECNET and
AppleTalk that set up the connections to particular servers, printers and
services.

2) Some bridges claim to filter based upon any bit pattern in the Ethernet
packet, what makes the KarlBridge so special?

Although it is true that some bridges have this feature it has been our
experience that they are hard to configure and limited in comparison to
the KarlBridge. This is because the KarlBridge has algorithm-based
filters as opposed to bitmask-based filters.  If the algorithm is flexible
enough then it will solve 90% of the needs much easier than the bit mask
approach.

3) I don't need protocol filtering, is the KarlBridge still a good choice?

Yes, in most situations.  The KarlBridge is a very low cost bridge.
It can clean up your network by filtering packets based upon:

  Whether the packet is a broadcast, not needed by some protocols.
  Whether the packet is a multicast, not needed by IP protocols.
  Whether the packet is from an invalid source address (ie broadcast or
	multicast address).
  Whether the packet is going to a "not yet learned" destination address.

4) When is it not a good idea to use the KarlBridge?

The KarlBridge is not as fast at forwarding packets as some commercial
bridges.  This extra speed may be needed in some situations where there is
very heavy file server traffic.  Frankly it has been our experience that in
all situations tested the speed difference is not noticeable (assuming the
bridge is built with Elite 16 Ethernet cards and a fast motherboard).

5) Is a 286 or 386SX really a good platform to build a bridge on?

It as been our experience (40+ bridges installed for over a year) that it is
a good platform.  We have had to overcome a lot of pitfalls of the standard
clone that the average vendor offers. It has been our experience that the
average systems integrator or computer store does not supply hardware
that is capable of withstanding heat, dust, restarting after power failures,
and consistent network traffic for months at a time that a bridge requires.
We have spent a lot of time to find a good, consistent and reliable
manufacturer of mother boards, with good BIOS, reliable design. We have also
set our supplier up to burn in the boards in a heat chamber (not done
by your basic clone retailer). We have also insisted on our supplier running
special tests for several weeks prior to shipping the bridge.  They have
done enhancements to the hardware themselves and have a commercial
KarlBridge product.

6) If I make my own bridge do I have to use the SMC Elite 16 cards?

No.  You MUST use SMC Elite 8 or Elite 16 cards with the 83C690 chip (all
new cards have this chip).  The Elite 16 is HIGHLY recommended due to its
superior speed.  There used to be a version of the KarlBridge program that
used the older discontinued WD8003 cards.  The WD8003 cards are NO LONGER
supported because they have the 8390 Ethernet chip which locks up under
heavy network load when it is used in a bridging application.

7) I like KarlBridge but I am concerned about building my network on PC clones.

Understood.  We at Ohio State University are on 24 hour call to repair any
of the 80 KarlBridges we have installed. We therefore buy the commercial
version from our supplier of KarlBridge systems. They are setup to sell very
reasonably priced high quality nice looking hardware. The philosophy behind
KarlBridge is to supply much needed boxes with modern features to the
worldwide networking community at a price below the cheapest standard bridge
available.

====================== Software Installation Notes ======================

It is assumed you have the following files that are contained in kbridge141.arc

	kbconfig.exe - KarlBridge Configuration Program.
	kbridge.com  - Executable image of KarlBridge for WD/SMC Elite 8
		       or 16 boards with the WD83C690 chip.
	readme	     - An additional copy of this file.
	kbpaper.txt  - A paper that I wrote about the KarlBridge.
	kbmanual.txt - An ASCII'ized version of the commercial manual
			(looks bad in ASCII but great in print).

Configure the kbridge.com file, by issuing the following command on your PC:

    kbconfig -f kbridge.com

Create a bootable floppy by issuing the following commands:

    format /s a:
    copy command.com a:

Create an autoexec.bat file that contains the single line "kbridge".

Copy the kbridge.com file and the autoexec.bat to the bootable floppy.

    copy kbridge.com  a:
    copy autoexec.bat a:

You now have a bootable KarlBridge floppy.

============================ Making your own ===========================

Hardware Specifications:

     1) 16 Mhz 0 wait state 286 or 386SX mother board or 386DX mother
	board with AMI BIOS, 512 Kbytes to 1 Megabyte of RAM, floppy
	drive and controller, it must be able to boot with no monitor
	and no keyboard.

     2) The speaker connection must be modified to power a front panel
	LED that signifies LAN traffic (Different mother boards need
	different types of modification). Without this modification the
	speaker will click.

     3) The floppy drive must be capable of withstanding a dusty environment
	such that if the system is operating for months at a time and then a
	power failure causes a reboot the floppy will still work.  This
	usually requires a modification to the case so that the air does not
	flow through the floppy drive itself.

     4) The entire system MUST be burned in for a minimum of 2 weeks with
	cycling temperature with full Ethernet load.

     5) Two SMC Elite 16 boards are required with the following setups:

	First  board: IRQ 3 I/O Addr 280, Shared RAM D000  (Remote Port)
	Second board: IRQ 5 I/O Addr 2A0, Shared RAM D400  (Local Port)

				- OR -

	First  board: IRQ 3 I/O Addr 280, Shared RAM E000  (Remote Port)
	Second board: IRQ 5 I/O Addr 2A0, Shared RAM E400  (Local Port)

	   (NOTE: The KarlBridge no longer overrides the configuration for
	    the Shared RAM address but does disable the IRQ on each card at
	    startup.  The Shared RAM Address used to be fixed to the Dxxx
	    space which caused problems with some newer 386sx machines.  It
	    was then changed to Exxx which caused problems with some older 286
	    machines.  KarlBridge now excepts either D000 & D400 or E000
	    & E400 as the SMC boards shared RAM addresses.)

If you chose to make your own clone WATCH OUT for the following:

     1) We have not tested the program with hardware other than a 16Mhz,
	0 wait state 286-16, 386SX-16, and 386DX40 with the I/O bus running
	at 8 Mhz.

     2) The 8 bit WD Elite boards with the 83C690 chip work well but at
	approximately 1/2 the speed of the 16 Bit WD Elite board.

================= Commercial Supplier of KarlBridge Hardware ==============

It is strongly suggested that you give our commercial supplier a call. We
have worked extensively with them and have set them up to build some VERY
nice turn-key clones with the KarlBridge software in them.  They configure,
heat test, and ship you a reliable and burned in system. They offer telephone
support, 1 year warranty, and software support.  They have also enhanced the
SMC Elite 16 cards by configuring the EEROM to make them more compatible with
a commercial version of the KarlBridge code. They also offer a remotely
programmable (through SNMP) Flash ROM based KarlBridge.  (The Flash ROM
based bridges are very nice; Ohio State University has upgraded all 80 of
their KarlBridges to use Flash ROM. The Flash ROM KarlBridge is only
available on the commercial version of KarlBridge.

The KarlBridge sells for $1195 in the USA and #1500 in the UK.

For more information contact:

Doug Karl		  KarlNet Inc.         Sherwood Data Systems, Ltd.
Ohio State University	  (614) 263-5275       +44-(0)494 464 264
kbridge@osu.edu		  sales@KarlNet.com    sales@gbnet.com

=================== What else are we working on? ======================

There are several hot projects in the works. They are primarily funded from
license fees from the commercial side of the business. It is real bad
to sell futures but since everyone else does why not....

    1) A lot of new drives for:

	- NCR WaveLAN driver for 2 Megabit, 5 mile wireless point-to-point
	  or in building 800ft connectivity. (This is in beta test).
	- New Ethernet board that has given us full wire speed in the lab.
	  (this board will be supported only on the commercial KarlBridge)
	- 56K/64K/T1/E1 dual card for a remote KarlBridge. (almost alpha test)
	- COM Port with 16650 Uart or ISDN cards. (almost alpha test)
	- FDDI -> [HELP! -> anyone know an FDDI ISA card with CAM]
	- Token Ring -> [Anyone know of source for a token ring packet, or
			 ndis driver]

    2) KBCONFIG enhancements:

	- New KBCONFIG based upon Borland C++ type menus. (in alpha test)
	- Provisions for KBCONFIG to write a filter definition language.
	  (in beta test)
	- X-Windows version of KBCONFIG (Summer 1993)
	- MAC version ->[ need volunteers for this one, please contact ]<-

    3) Bridging/Routing enhancements (end of summer):

	- Support for Spanning Tree and Source Routing
	- IP Routing
	- IPX/SNMP Support

    4) Filter Enhancements:

	- Better security features like (Notification of attempted break-in)
	- Extensive support for Novell SAP filtering (in alpha test)
	- Support for LanManager service filters (this fall)
	- More than 10 entries per menu (for the commercial version)
	- Less then 10 entries per menu (for the free version)

=================== If you chose to use the KarlBridge ====================

Please send e-mail to kbridge@osu.edu with your name and surface mail
address and we will add you to our database so that we can notify you of
future updates and other products. (Yes we are working on some very
exciting related products)

Thanks for trying out the KarlBridge and please feel free to respond
with your questions and comments.

Doug Karl
Senior Computer Specialist
The Ohio State University
kbridge@osu.edu
