Newsgroups: comp.dcom.lans.misc

In comp.dcom.lans.misc, tsjoit@htsa.aha.nl (T. H. Tsim) writes:

 
    Dear netters,
 
    I am looking for comments for this problem:
 
    I want to connect a LAN of PC's with a remote SCO Unix Host:
    The Lan is working with Novell's Netware.
 
    W -|
       |
    W -|
       |
    W -|-H--^........^--Unix
       |
    W -|                    W=workstation
       |                    H=Novellserver
    W -|                    U=SCO Unix
 
    I was thinking of using two bridges (but I don't have experience with bridges)
    in order to 'bridge' the distance through x.25 or leased line. Could someone
    give me some usefull hints ?
 
    The second part I'm not familiar to is how to connect the workstations with
    the Unix-Host, after a lot of thinking, browsing and studying, I think TCP/IP
    could be a good solution.
 
    But again, I lack of practical knowledge, in order to enable coexistance of
    IPX and TCP/IP. I've heard of ODI-drivers, packet-drivers,machine requirements,
    SLIP and PPP. After a lot of studying documents and books, I still can't see
    the whole picture of the puzzle (maybe some pieces are missing ?)
 
    So please, give me some comments, critics, information to indicate I'm one the
    right track (or not).
 
    I'm a student on co-op assignment :-)
 
 
    Greetings from Holland
 
 
When you are connecting the remote SCO UNIX server to the novell LAN,
it really depends on what you want to do. If you are just interested in
application access on the SCO UNIX (i.e. accessing an application on the
SCO Unix through terminal emulation) from the PCs on the LAN, then a
asynchronous gateway or an X.25 gateway will suffice. There are many
products that can do these (e.g:- EICON gateway, Novell has their own too!).
If you are using X.25 gateway, make sure you have X.25 an HPAD support
on the SCO Unix host.

Of course you can achieve the above functionality through TCP/IP by 
employing bridging or IP routing (dedicated/non-dedicated). You may find
them a more expensive approach (telecommunication requirement is higher,
etc).

However, if requirement dedictates that you need file services integration
between the Netware server and SCO Unix server and printing services
integration, then you will need to  use a bridge or router.

To do the above, you can use NFS NLM on the Netware server (I presume it
is a 3.11 Netware version) and run NFS on the SCO Unix. This will allow
file sharing and access by both Netware clients (PCs) and SCO Unix users.
Netware users on the LAN can access the files on the SCO Unix transparently
(they don't see NFS, they see them as part of Netware volume). likewise,
SCO Unix see Netware volumes as NFS volumes). Integration of the print
services can be done through a third party product (I think it is reflex?
I can't remember the name). Basically, it uses the "lpr" to support remote
spooling. And SCO Unix does support "lpr". Now all these only concern 
integration of services and nothing about bridging or routing.

To interconnect the two networks, you can use bridges. Please take note
of your briges capability. You want to minimise non-TCP/IP packets from
going over to the SCO Unix Network. Netware (i.e. IPX packets). If you
are using bridges, make sure that you have sufficient filtering
capability to stop IPX traffic from going to the SCO Unix host. 

Dedicated routers are an alternative to bridging but they can be expensive
for your simple application. You can turn the Netware server (3.11 I 
presumed) into a non-dedicated IP router and use bridging on the IP
segment of the Netware Server. If you application requirement is of
high traffic in nature, then this can be hindrance to your netware server
performance. In that case, you use a dedicated IP router.

As for TCP/IP software on the PCs, you can use LAN WorkPlace from Novell
(they use ODI) or ARPA for Netware (from HP, they use NDIS). Both allow
IPX and TCP/IP protocol stacks to coexits on the same LAN card. You may
want to check out the support for your existing LAN cards.

	PC
	|
	PC (terminal emulation)
	|
	PC
	|
	|
	Netware Server
	|
	|
	X.25 Gateway <-----X.25 Network--------> SCO UNIX


	(X.25 Gateway Approach - terminal access only)


	PC
	|
	PC (Can also run PC/NFS, independent of Netware Server)
	|
	PC (runnning LAN WorkPlace)
	|
	|
	Netware Server (running NFS, TCP/IP)
	|
	|
	Bridge<-------------------------->Bridge----SCO UNIX (TCP/IP,NFS)
	(Filter off IPX packets)

	(Bridge Approach 1)


	PC
	|
	PC
	|
	PC (running LAN WorkPlace)
	|
	|
	Netware Server (running NFS, TCP/IP routing turned on)
		|
		|
		Bridge <----------->Bridge-----SCO UNIX (TCP/IP, NFS)



	PC
	|
	PC
	|
	PC
	|
	|
	Netware Server
	|
	|
	IP Router <--------------> IP Router-----SCO UNIX (TCP/IP,NFS)


	(Dedicated Router Approach)


I hope you will find these helpful. Please note the opinions expressed is
my own and is independent of my employer.

Regards,

David LEE