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Testing Connection using TCP/IP
Usually, when connecting Windows95 systems,
NetBEUI is used as network protocol, because the Microsoft
"win95-server" (also called "Microsoft File and
Print Sharing") can be most easily setup with NetBEUI
protocol (you can also used TCP/IP or IPX/SPX, but that is a
little more complicated)
But when you think, that everything is setup properly, but you
CANNOT get any connection, you need to establish first, what and
where something is wrong in the complete setup:

whether the hardware (network board and cables) work properly to
identify, whether you have a Hardware or Software problem.
For that, the TCP/IP protocol supplied with Windows95/98/ME/NT4/2000 offers
a small,
but powerful tool called : 'ping'. (You can also use the NET DIAG test), allowing to
make a connection test on a much simpler setup, but TCP/IP PING
can also be used to test a WAN
connections) :

"What is ping actually doing ?"
Remember the movies on sub-marines, where they are searching each
other sending out a search-signal , which sounds like 'ping' and
where they get back an echo from another sub-marine ?
That is EXACTLY, what the 'ping' utility does:
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send out a signal |
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and get an echo back |
That is part of any TCP/IP ( regardless of the
operating system): on receiving a 'ping', it sends the signal
back to its origin.
To setup TCP/IP for this 'ping' test, in case it is not yet
already installed
( for more detailed info: TCP/IP basics) :
* add in addition to your existing network protocol TCP/IP (in
the "network" applet in "Control-panel",
select "add"),

then "protocol",

choose "Microsoft" and then the "TCP/IP".
* do NOT exit the Network applet, you first MUST configure
TCP/IP.
(If you do EXIT and restart, you get a warning on
"DHCP": ignore it, go back to the Network in
Control-panel and configure the IP-address)
* select the TCP/IP-protocol in the Network-applet, then select
"properties":
* on the tab:"IP-address", select the radio-button to "define the
IP-address", enter on the first PC as address 192.168.10.1,
on the second PC as address 192.168.10.2, enter as subnet-mask
255.255.255.0,:

then close it.
* reboot Windows.
If TCP/IP is installed but configured to:
"obtain an IP address automatically":

then you need to find out, which IP-address has
been assigned by a DHCP-server or by the
Windows98/ME/2000
IP-Auto-Configuration : use on the
Start-menu the RUN-command to
execute "winipcfg" (on a Windows95/98/ME
system, on Windows NT4 and
Windows 2000, open a command-prompt window and type the command :
"ipconfig" ) :
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Select from the drop-down
your network adapter :

(often, the PPP-Adapter for the Internet connection via
modem is the first selection in the list).
Verify, that values are listed for
IP-address and
Subnet Mask. |
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If the IP-address and Subnet Mask are
listed with
"0.0.0.0", then there is NO IP-address assigned
(no DHCP-server on the network and/or the
IP-Auto-Configuration did not work )
and without an IP-address, TCP/IP networking
does NOT work ! |
Open a DOS-box, and on PC#1, typ: ping
192.168.10.2
This will send now an Ethernet package to the system with that
IP-address, which is here PC#2. And every system properly
configured with TCP/IP will send that packet back.

If it comes back, then your Ethernet board and cables seem to be
fine, you have a network software setup-problem, check the setup
of the protocol (if IPX/SPX was used), check permissions and
sharing, user-names and workgroup-names.

But if 'ping' does NOT get an answer back (' Request timed
out'), try first if you can make the
'ping' from the other system (sometimes 'ping' works only in ONE direction, it may have been
disabled on one system).
If 'ping' does not work in both
direction, then you have most probably a hardware problem,
which could be the network board, the cable , the hub(if using
10baseT) or the t-connectors or the
terminators (if using 10base2). (no joke: I know somebody, who
went from Los Angelas to Hawaii
just for that, he swapped a T-connector and then the network
worked, checking later that
t-connector showed a microscopic crack, not visible with the
naked eye).
If you are using a FastEthernet network, it could also be that
the network card and the hub did
not properly configure themself for the Media Speed and/or the
Duplex-Mode.
In professional networks, I would suggest now the use of Ethernet
cable testers, which put a test-signal on the cable and can tell
you, if the cable is o.k. or bad and then also WHERE is is bad.
This error message of PING indicates, that you
tried to test the connection
to a system NOT on the same subnet (where a direct connection is
possible),
but via a Gateway/Router on a different subnet (for more info on this issue,
please see the section of Gateway/Router of TCP/IP-Bascis).
But you did not define a Gateway address:

Enter a valid Gateway/Router-address:

When testing a TCP/IP connection via a Gateway/Router, you need
to be
aware about very single step:
1) The PING signal is send to the Gateway/Router (is the gateway defined ?)

2) The Gateway passes the PING signal on to the destination
system
(or if required to the next
Gateway/Router, until it reaches it destination subnet)

3) The destination signal replies by generating the PING ECHO
(is the destination system configured
for the Gateway/Router, so that it is able to send back the
signal ? )

4) The Gateway/Router receives the PING Echo and sends it back to
the
source-system:

When setting up Gateways/Routers, don't forget to setup ALL
system, which the signal is traveling through from the source to
the destination AND BACK.
And if you have problems, enter the PING command on both systems,
it may give you an error message indicating the problem (like a
missing Gateway definition).
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