Port forwading - special software or operating system function?

[Oliver Ekeis]

Hi NG,

I hope, I'm not OT here. Maybe, this question was asked
some time, but I haven't found it yet. So a priori I'm sorry for that.

I want to use a simple Windows 2000 PC (Linux is unfortunately
not possible) with two network cards as a gateway from one subnet A
to another subnet B. Especially the port forwarding function is important
for me.

I want the port fowarding gateway to listen on several ports in subnet A
and to forward the packets to selected ip addresses (definition according
to defined table) and ports in subnet B. So every simple and cheap
DSL-Router with web interface does this task.

Is it possible to use integrated operating functions to achieve this
or do I have to use a special software for that. If I have, could you please
recommend some (maybe with links)? Of course it should be cheap
or maybe free of charge.

Thanks for your patience and for your help.

Oliver.

 

[Phillip Windell]

I want to use a simple Windows 2000 PC (Linux is unfortunately
not possible) with two network cards as a gateway from one subnet A
to another subnet B. Especially the port forwarding function is important
for me.

It requires Windows Server 200x, not Windows 2000.

"Port Forwarding" is not an accuarte term although it has been made popular
by the SOHO (simple cheap DSL-Router "things") market,...but it is not a
real term. The real term for what you are asking about is Static NAT but I
don't think the SOHO market has figured it out or ever will. The
definitions of terms in the IT industry has become "shambles" in the last
couple years since DSL and Cable Intenet has become popular..

I believe RRAS (Windows Server) calls it "services" which is fairly accuarte
since it is making "services" on a Trusted LAN available to the Untrusted
Network. I don't know what Linux's IP Chains or IP Tables calls it.

Ports are never "forwarded",..ports don't go anywhere (IP#s do). Ports do
get translated as in PAT (Port Address Tranlation), but that is not the same
as what you are asking about.

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com
-----------------------------------------------------
Understanding the ISA 2004 Access Rule Processing
http://www.isaserver.org/articles/ISA2004_AccessRules.html

Microsoft Internet Security & Acceleration Server: Guidance
http://www.microsoft.com/isaserver/techinfo/Guidance/2004.asp
http://www.microsoft.com/isaserver/techinfo/Guidance/2000.asp

Microsoft Internet Security & Acceleration Server: Partners
http://www.microsoft.com/isaserver/partners/default.asp

Deployment Guidelines for ISA Server 2004 Enterprise Edition
http://www.microsoft.com/technet/prodtechnol/isa/2004/deploy/dgisaserver.mspx
-----------------------------------------------------

 

[William Lipp]

I want to use a simple Windows 2000 PC (Linux is unfortunately
not possible) with two network cards as a gateway from one subnet A
to another subnet B. Especially the port forwarding function is important
for me.

I want the port fowarding gateway to listen on several ports in subnet A
and to forward the packets to selected ip addresses (definition according
to defined table) and ports in subnet B.

I think the freeware AnalogX PortMapper does what you want.

http://www.analogx.com/contents/download/network/pmapper.htm

 

[Kurt]

Windows 2000 is capable of serving as a NAT router. Look up Internet
Connection Sharing in Windows help (what you're doing won't have anything to
do with the Intrernet, but it'll work just as well on local subnets. You'll
have to address routing according to your network setup.

....kurt

 

[Oliver Ekeis]

Thanks to all.

Maybe I was a little inaccurate with my expressions. But the
Port Adress Translation (PAT) was the thing I was looking for.

My understanding of PAT:
PC in Network A -> PAT-W2K-PC -> PC in Network B
192.168.1.43 -> 192.168.1.1 // 192.168.99.1 -> 192.168.99.216
with PAT-table of 192.168.1.1 // 192.168.99.1:
translate 192.168.1.1:XXX to 192.168.99.216:YYY

Request:
From 192.168.1.43 I want to use a special service (#YYY) of 192.168.99.216.
I configure my 192.168.1.43-PC to access 192.168.1.1:XXX and the
PAT-gateway forwards the packet automatically to 192.168.99.216:YYY

So I think the AnalogX tool PortMapper matches exactly my needs.

Regards,
Oliver.

 

[Phillip Windell]

Thanks to all.

Maybe I was a little inaccurate with my expressions. But the
Port Adress Translation (PAT) was the thing I was looking for.

Ah! OK, so that was what you were looking for? Yea, those other products
should help with that,...otherwise you'd need RRAS with Windows Server.

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com
-----------------------------------------------------
Understanding the ISA 2004 Access Rule Processing
http://www.isaserver.org/articles/ISA2004_AccessRules.html

Microsoft Internet Security & Acceleration Server: Guidance
http://www.microsoft.com/isaserver/techinfo/Guidance/2004.asp
http://www.microsoft.com/isaserver/techinfo/Guidance/2000.asp

Microsoft Internet Security & Acceleration Server: Partners
http://www.microsoft.com/isaserver/partners/default.asp

Deployment Guidelines for ISA Server 2004 Enterprise Edition
http://www.microsoft.com/technet/prodtechnol/isa/2004/deploy/dgisaserver.mspx
-----------------------------------------------------