On Sun, 2005-12-18 at 20:20 -0500, Paul W. Abrahams wrote:
On Sunday 18 December 2005 8:00 pm, Joe Zien wrote:
I got your e-mail on suse-linux-e@suse.com and notice you use comcast.net with a cable modem. I just ordered suse 10 and am a comcast cable user and plan to go broadband with a comcast cable modem, at present I only have dial-up. Did you have any problems using a cable modem and could you give me any tips how you set it up in suse 10? Any help would be appreciated.
I'd suggest putting a router between the cable modem and your machine, even if you have only one machine, since that will provide a firewall. Otherwise you'll have to deal with all the firewall issues since your computer will be on the front line of the Internet battleground.
The most important aspect of putting a device between your PC and the modem is that the device takes care of NAT(Network Address Translation) from/to a public IP to/from private IPs. In case you hook up the modem directly into your PC, your PC needs to have a public IP address assigned by Comcast, let's say 24.120.10.121, which is accessible from anywhere around the world. That's why you HAVE TO set up Firewall on your machine. On the other hand, if you put a device in-between, the device MUST have two interfaces (could be logical interfaces): one has 24.120.10.121 and the other has any private IP address, let's say 192.168.1.1/255.255.255.0. And your PC can have one of IPs in the same subnet, 192.168.1.2-192.168.1.254. It can be assigned via DHCP from the device or assigned statically/manually. This case, everybody outside can try accessing the device using 24.120.10.121 but can't access your PC because of NAT on the device. Of course, if a hacker found a way to break into the device, the hacker can have many ways to attack your PC, like setting up port mapping or whatever. But the chance the hacker or viruses can attack your PC is much less than you hook up the PC to the modem. Needless to say, if you need or decide to add another PC, it would be much easier than installing another NIC into your PC to connect your second PC. Toshi