ok so here is the situation.... i have a Dell in my living room and a HP in by bedroom i also have dsl internet service. now i am wondering if i could have a dsl modem hoked up to my Dell and a seprate dsl modem hooked up to my HP and have them both connected to the internet at the same time? so i guess what im asking is can i have two computers hooked up to seprate dsl modems and be able to surf the internet while they are both connected to the dsl service? Thanks for the help in advance
is ur dsl modem usb or ethernet? just thinking of other options like buying a switch which is probley going ot be a lot cheaper.
You have one phone line only per DSL modem device. Just get a wireless router and PCI,USB, or card and it will do the trick.
the dsl modem is a ethernet and usb modem but i can just plug my second computer into the modem with a network cable. say i have my dell and my hp computer pluged directly into the same modem via ethernet cable (the modem has 3 ethernet plugs). Would there be any sort of file exchange between the two computers, directly or indirectly? if i got a virus on the dell could it travel to the hp because they would both be pluged strait into the same modem?
I agree with ddp. If you haven't purposely configured your setup for networking, and are only sharing the modem for Broadband, then you should be fine.
Actually it is possible, for example the Slammer worm worked by scanning other pcs to see if they had the same vulnerabilites. It would start by scanning the local subnet and would infect PCs with the vulnerability regardless if they had file and print sharing turned on or not. Even if both pcs are configured to not share files, they still see each others broadcast packets if they are on the same subnet, which they would be on the LAN side of the DSL modem. Say your modem was 192.168.1.1 with a subnet mask of 255.255.255.0. That means everything on the network that has an IP of 192.168.1.x is on the same subnet and would still see broadcast packets from the others. Slammer would send a broadcast to 192.168.1.255 which every PC on the local subnet would respond to. If the broadcast returned let the infected PC determine that others were vulnerable then it would infect them.
@Xian So what you are saying is that no matter your setup, single or multiple, you are vulnerable. Or in other words, it makes no difference whether you are networked or separate, just that you are connected to the internet by an ISP and that again can make you vulnerable. So it would not be the “DELL” giving the virus to his other PC but the ISP giving the worm to both. Or did I miss something here?
Yes, for some worms just being connected and unpatched is all it takes. This happened at work, there was an outbreak of Sasser I think or maybe one of the Netsky variations, and the firewalls had the ports it was using blocked. I work for a large company with thousands of PCs so it is nearly impossible to patch everything in one fell swoop. The firewalls were blocking the worm from entering from the internet, but we still got hit. Someone brought an infected laptop in and plugged it in, effectively bypassing the firewalls. Same scenario as Spyder22 was asking about, the work PCs aren't configured to share files with each other but they were still infecting each other once the worm got in, that's why I said it is possible for one to infect the other. Say his Dell goes to a hacked website that has an exploit on it. Even though he never visits that site with his HP, it's possible for his HP to get infected from the Dell since they are on the same network.
In the instances that you mentioned, would Windows XP firewall, if active, be enough to stop either of the two that hit your company?
Windows firewall would have been able to block most of those worms, especially for a home user. However there are already known ways around the windows firewall and it will probably just be a matter of time before they are used. I saw proof of concept code at insecure.org over a year ago. I said they would have blocked them for a home user because things like Sasser used ports 69, 445, and others. In a corporate environment it is much harder to block those ports internally. For instance, port 69 is TFTP which is what Cisco Routers use to back up their configurations.
my dsl modem has 3 ethernet ports and one usb port, so would it make a diffrence if i had one connected via usb and the other one connected via ethernet. would the pc on the usb port be safer than the pc on the ethernet port (or vice versa)
i beleive that the usb port is just made like an ethernet port when the software is installed so none safer mate
It would make no difference from a safety point of view. As stated earlier, using normal safeguards, you will be fine.
