What do I need?

[fsvara]

Now that, thanks to a post below, I know more
or less the difference between routing and ip
masquerading, I have amore practical question: Which of both do I need?
I'll first tell you about the actual situation:
I have a little LAN of 7 computers with mixed
operating systems (Windows 95-98-NT-Linux).
Additionally I have an out-of-the-box YAMAHA router that successfully connects the network
to the internet via a dialup connection it dials when someone tries to access the
internet. All computers can access the net simoultaneously.
I have always referred to this machine as 'router', without thinking much about it.
Now a dialup connection isn't ideal. I want to get ADSL. Since the YAMAHA machine doesn't
work with ADSL, I thought I could set up a spare computer just like the YAMAHA machine just with the difference that it will have two ethernet adaptors and will 'route' ADSL.

Now that I have read a little about the matter I am a little confused: What do I actually need? IP masquerading or routing? How can I set this Linux computer up so it does the same as the YAMAHA machine? What tools will I have to use?
Thanks in advance you communication gods http://www.linuxnewbie.org/ubb/smile.gif
fsvara

[iDxMan]

Sounds like you just need to setup a simple firewall/router using ipmasq to share the connection.

Tools:

roaring penguin pppoe for DSL

use the following to masq:

#!/bin/sh

INTERNAL_MASK="192.168.0.0/24"

ipchains -M -S 7200 10 160
ipchains -F forward
ipchains -A forward -s $INTERNAL_MASK -j MASQ


Just make sure masq support is compiled in the kernel..

That should be enough to get you started...

-r

[dave1]

you could also use freesco, there is good nhf for setting this up.

[fsvara]

I see a lot of people saying firewall/router... What do you mean by this? A firewall AND a router, a firewall OR a router or is it the same? I don't hink so.
And something else:
Will all connections trhough the gateway work
as normal? Like playing in the batlle.net for
the win computers or using any other services
like napster or video conferencing?

[Gaccm]

a firewall/router is a firewall that has the abilities to route. And if you want one thats newbie-friendly get PMFirewall http://www.pmfirewall.com/PMFirewall/#download

[Fandelem]

A firewall is: "Any of a number of security schemes that prevent unauthorized users from gaining access to a computer network or that monitor transfers of information to and from the network."

A router is: "A device which forwards packets between networks. The forwarding decision is based on network layer information and routing tables, often constructed by routing protocols." Note: This *can* be a computer (as a device), *or* specifically, a "router" (like a cisco 2500 router, for example).

IP Masquerading: "the IP Masquerade feature allows other "internal" computers connected to this Linux box (via PPP, Ethernet, etc.) to also reach the Internet as well. Linux IP Masquerading allows for this functionality even though these internal machines don't have an officially assigned IP addresses. In addition to the added functionality, IP Masquerade provides the foundation to create a VERY secure networking environment. With a well built firewall, breaking the security of a well configured masquerading system and internal LAN should be considerably difficult."


Okay, now if you read those definitions, you might have a better understanding. If not, I'll try to put it simplier- you *need*
1. a router (either a computer *acting* as a router, or a router)
2. IP Masqing (if you have more then one computer that you want internet access)

now then, if you want *any* security at all, you *need*
1. a firewall
2. maybe portsentry, etc...


combined, this is why people sometimes say, "oh yes, you will need a router, firewall, and IP masqing"

I hope this helps..

and if you need any additional help, try my newly made home networking howto.. i want input on it, dernit.. http://www.fandelem.com/nhf.html

regards,

~kyle

[iDxMan]

Originally posted by fsvara:
I see a lot of people saying firewall/router... What do you mean by this? A firewall AND a router, a firewall OR a router or is it the same? I don't hink so.
And something else:
Will all connections trhough the gateway work
as normal? Like playing in the batlle.net for
the win computers or using any other services
like napster or video conferencing?


Nice explanation above. No need to reiterate.


I believe the main reason for a "firewall/router" phrase usage, (or at least in my case) is that you'll be setting your linux box up for [hopefully] both of these items. You can leave off the firewall part, but obviously you then open yourself up to possible attack.

More or less its less typing for me. I'd rather say "firewall/router/nat box" than typing out 3 lines as to what *exactly* those 3 are.


-r

PS. b.net games will be very poor behind a MASQ setup. Its blizzard's fault, but they don't seem to want to fix it. http://www.linuxnewbie.org/ubb/frown.gif

But yes.. Most other games/applications work as normal via ip_masq. There are a few that don't, but some have modules to fix this. (eg: icq, ftp, quake3 something)


[This message has been edited by iDxMan (edited 04 November 2000).]