Hi guys. I have a basic issue which I hope you can help me with...


I have 2 PCs. A newer 1 which I use solely for work-related stuff, and an older 1 which I want to use for general suff (i.e. downloads, music, surfing the net, games etc). My new PC is connected to 512 broadband by a USB ADSL modem.

I'd like to connect both PCs to the net and be able to transfer files between them as fast as possible. Security is a big issue, so I think a crossover cable is out, as I'm guessing it'd expose my new PC to the same 'baddies' which my old one acceses. Before I think about a router/modem, I was wondering if I could achieve what I wanted with a data transfer cable between the PCs and some type of USB splitter/header (if the product exists!) so I could connect them both to the same broadband modem? :?

Is this possible? (if it'd mean they couldn't both be online at the same time it wouldn't be a problem).

You can find USB-based LAN stuff out there; I've never tried to set one up or use one, so I beg off on that question.

Regarding your other issues. Yes, you can use a crossover cable and set up your work computer to share the internet access, but your work computer will need a second NIC. However, without a router, your entire in-home network is exposed to the internet, at least to some extent. It also has the disadvantage that the work computer has to be on for the old computer to access the internet.

If you are concerned about security, I would recommend a router between your DSL modem and your computers. Most routers these days have a built-in switch, so you just plug each computer into its own port on the router. The firewall in the router will help with net-based attacks or snooping. I'd also recommend a software firewall on each computer.

If the router you get does not have a built-in switch, then get an ethernet switch to go between the router and your computers.

Thanks for the quick reply Ice.

OK great, in that case I'll probably go for a router/modem/firewall with a built in switch: kill 4 birds with 1 stone. I won't be connecting them wirelessly, as my PCs are just a few feet from the modem, but I may go for wireless compatability too (future-proof it, & ADSL2?). Any recommendations, or any to avoid? (I'm based in UK)

I have a software firewall too, hopefully I won't get conflicts. I do have 1 more question... I think both my ethernet cards are 10/100. Will the speed of transferring files between my PCs be limited by my broadband speed, a slow 512k? As I was considering this cable: Data-Transfer Cable :?

If you're not going to use wireless right away, disable it in the router setup just to avoid freeloaders.

If your DSL provider is tied to the MAC address of your current modem, you may need to deal with that. Talk to your provider.

Your internet connection speed will have no effect on how fast your two computers communicate with each other. Your two computers will communicate at the throughput rate of the router's LAN switch, probably very close 60Mbps or higher effective throughput. Most switches built into routers these days are pretty efficient. Max performance (also max cost) is by having everything separate - modem, router, wired switch, and wireless access point. For most home / small office users, the extra performance is not worth the extra cost.

The USB-to-USB data transfer cable will be faster than your 100Mbps LAN ... it should be 2 - 4 times faster. USB has quite a bit of overhead, so it won't reach 480Mbps, but it should easily be faster than a 100Mbps ethernet LAN. As I said above, though, I have no experience with this kind of equipment or setup.

Thanks again Ice. You're a legend and a saint!!

I'll ring my internet provider first thing tomorrow to double check that I'll be able to use another modem/router to the one which they supplied me with. Then I'll get online and order a new product. I'll leave the USB data-transfer cable for a while and see how quick the router can transfer files first.

I'll post back to advise how I got on, hopefully this thread can help other people too.

What model of ADSL modem do you have (OP)? chances are that it is already running NAT/DHCP to your "network" at home, meaning the LAN interface, whether it be USB or Ethernet.

Why are you (the OP, N8an) using the USB connection to 1 of your computers anyways if it has Ethernet? You are no more or less secure by using a different connection type to your ADSL modem versus Ethernet. Find out the model of ADSL modem, and look at the specs, or let us know the model number and I might know or be able to search the net for it.

If it does indeed have NAT/DHCP running, then buying another home router is pointless unless it's for wireless, because you're running through 1 NAT/DHCP router to another NAT/DHCP router. You can find this out by going to your work PC, and going to Start menu/run/type CMD and hit enter/type IPCONFIG and hit enter. if it starts with 10.x.x.x or 172.x.x.x or 192.168.x.x then you are indeed using NAT. let us know the results of the IPCONFIG, it will tell us if you need a router or not. IF it's working the way I think, you could just get a network switch and have absolutely 0 configuration to do, just plug ethernet cables from both PC's to the switch, and a 3rd ethernet cable from any port on the switch to the ADSL modem.

I understood him to be saying he was going to replace his modem with a new combo modem/router, not connect one with the other.

It is possible he already has a modem/router, but he indicated he was connected to the modem via USB.

A DSL "modem" does not normally contain full router functions (my experience, anyway) and does not normally contain an ethernet switch. It is intended as a one-to-one connection between the WAN and the subscriber's computer.

My home DSL provider supplied me with (actually, rented to me ) a combo modem, router, switch, and wireless AP. One of my clients (a small business) has a DSL modem only, so a router, switch, etc., is downstream of the modem to run his LAN.

Siemens, for one, used to make a USB DSL modem that had no RJ45 connectors on it.

I know the difference between a modem and a router/gateway when I am looking at network technology, but the OP might not have as much experiencing the 2. The word Modem has become muddied with too many incorrect uses. Even an ADSL "MoDem" isn't technically a modem in a traditional sense of dialup connections, but the term still stuck around and I guess it still applies, since ADSL still sends a signal over a phone wire, and Cable service uses a non-configurable (for the most part) "MoDem" for it's service. That's why I was asking for the model number so that I could find the specs for the system online and find out more about what might help the user out. :-P

Touche. I knew they were out there, but they aren't too common, and didn't know of any specific brands or models.

Good point. I was just explaining my response, not suggesting you didn't know the difference.

True... It would be more accurate to call them digital transcievers.

Thanks alot The_Taker & Iceblue, I appreciate all the help. I do have 1 problem with this stuff though, and my 1 problem is this: I don't know what the heck it all means!!

From what's written on it, it looks like it's a Thompson Speedtouch 330 ADSL modem. It's quite basic.

For some reason the modem only has 1 output, which is USB, and it looks like the lead isn't detachable.

Wow, if I could set it up that way it'd be great. It sounds simpler at least.

The results of the IPCONFIG are:

Windows IP Configuration

Ethernet adapter Local Area Connection:
Media State: Media disconnected

PPP adapter Speedtouch Connection:
Connection-specififc DNS Suffix:
IP Adress: 84.7etc...
Subnet Mask: 255.2etc...
Default Gateway: 84.7...

I hope that helps. What does it tell us?

Armed with the model of your DSL modem, I can safely tell you that you can set aside the choices The_Taker mentioned, since they will not work with your modem.

Your modem is USB connect only, does not support NAT (Network Address Translation), does not support DHCP (Dynamic Host Configuration Protocol) and does not contain any firewall functions. It is basically a direct connect of your computer to your ISP's server and that is it. As you said, very basic.

You can provide internet to your other computer by plugging a crossover cable between the two computer's NIC's and then setting up your home network using the Windows setup wizard and selecting the option that you are sharing the internet connection through one computer. You wouldn't need to mess with any USB switches or such, and the only thing you would have to buy would be a crossover cable (RJ45, Cat 5e). If you go this route, make sure you get a "crossover" cable. It is made for direct connection between two computers without an ethernet switch/hub/router in between.

The advantage of this approach is it is cheap.

The disadvantages of this approach are, first, your work computer would need to be powered on every time you wanted to use the internet with your old computer, and second, you have no hardware firewall protections. You're relying on your software firewalls only.

Your other options would require you to replace the modem. You do not need to replace it with anything too fancy. Chances are your ISP has an arrangement with Thompson and can upgrade your modem to one that includes a router (NAT, DHCP and a firewall), such as the Thompson 510. This device does not include an ethernet switch, so you would need to buy one of those. Or, perhaps they can supply you with the Thompson 546, which includes a 4 port ethernet switch. Thompson also has some models with wifi built in.

I don't know your fee arrangement with your ISP. It is possible they will want to increase your monthly fees for a multi-computer service, and increase your monthly lease on the equipment (if you are paying a monthly lease on your current modem).

It would be better to get them to take back the modem you have, remove the monthly lease altogether, and you buy your own modem, router, etc.

What he said...on all accounts.

The ISP I used to work for didn't offer any "modem/USB" only setups like you have N8AN.

Good luck!

Thanks alot for the reply Iceblue. This is really useful information and you've saved me one hell of a lot of time.

Yeah, I did think about the crossover cable option. But I felt it might jeopardize what I wanted to achieve security-wise...
I want to get my old PC connected to the net so that I can use it for general stuff (d/loads etc.) and not even expose my work PC to that type of thing. But because the connection to my old PC would be going through my work PC (via a crossover cable) I'm guessing that my work PC would be exposed to exactly the same 'baddies' as my old one.
Does that sound right? Or would the work PC just have the old PCs connection running through it without the threats? :?

Exactly. I was looking at modem/router/firewall/switch combos online a few hrs ago. I'm thinking of changing service providers in the next few months so I'd need one that's as compatible as possible. I was actualy looking at the Thompson Speedtouch models. Maybe the Speedtouch 585i...? Seems to offer everything I need & it's reasonably priced. What do you think: Speedtouch LINK. ?

if you're changing ISP's, who are you changing to? the new ISP might already offer a router that matches what you're looking for, but you can still provide your own...just don't expect your ISP to be too friendly (but be pleasantly surprised if they are) if it's a brand or model they don't support.

the link above would be perfect criteria for what you're trying to do. As far as not exposing your computers to things on the internet and having certain configurations be safer than others, it's unlikely that running 1 PC through the other would grant any advantage, unless it's got GREAT firewall software designed to defend a network against attacks. Any computer that is connected to the internet (aka ethernet to a router, or usb to a modem) needs the most recent security updates and patches, as well as current spyware/anti-virus software. the router in the link will provide NAT protection, which is the most basic "firewall" because it masks your computer behind it, as far as what things on the internet see from your internet connection. DHCP just means you don't have to configure each PC, just plug it in and it works for the most part.