Here’s my situation. I have two networks in my house, Comcast Cable and Earthlink DSL. My computer upstairs is hooked up to Earthlink, and my computer downstairs is hooked up to Comcast. I’ve mostly been using the downstairs computer to play World of Warcraft, where I’m in a high-end raiding guild. I need my signal to be solid with low latency for raiding, but lately my Comcast latency has been intermittently terrible (not sure why–it’s been flawless since I got it about two months ago up until about three days ago when it’s ramping up to over 1000ms latency even after I reboot the modem and router).
My computer only has one Ethernet port, which is currently occupied with a cable leading to the Comcast router. What I’d like to be able to do is run another cable downstairs from the Earthlink router, plug both of them into my downstairs computer, and be able to switch between the two of them. Is there some sort of splitter thing that I can plug into the computer’s ethernet port, then plug both Comcast and Earthlink cables into them and switch them depending on which one has better latency at the time?
Ideally I’d like to be able to do this on the fly (maybe shut down Warcraft, switch, then fire WoW back up again–but not have to reboot the box). Is this possible?
BTW, the issue is not with my computer since my spouse, who uses a Mac connected wirelessly to the Comcast connection, experiences the same problems at the same time I do on my PC.
For starters, two different ISP connections have two different IP addresses for two different networks. You don’t want any “crosstalk” between either company’s connection. Not being a network engineer but it seems to me you risk each opposing network if both are physically connected at the same time. The safest bet would be to swap network cables, but you have to wait for the new network to identify itself.
Or connect via cable vs wireless. You can disable / enable / switch networks just by enabling / disabling the proper network. You will still have to allow time for each connection to reenable properly.
Or connect via two different wireless connections.
In any case, you will probably have to “release” the IP address, disable the connection, switch ISPs, enable the connection and then renew your network lease (with new IP) just to connect between the two ISPs.
What you’re looking to do is a basic form of load balancing or gateway routing. As you’re that one in a zillion home users that has two active broadband lines to pick from, there’s just no market for this. Normally, this is only done at the enterprise level, with equipment that costs tens of thousands of dollars.
About all you’d be able to do is run a cable from each connection’s router to your desk, then plug in whichever one you want. If you configure your PC for a static IP and configure each router to look the same in terms of gateway IP, subnet and DNS servers, you might be able to change connections on the fly without rebooting, but I make no promises.
If the Comcast connection is acting up, why don’t you get rid of it and just use the DSL?
Leave both connections plugged in all the time, but disable one or the other via the Network Connections icons.
The computer won’t be running routing, so there’s no “cross-talk” danger. There’s no reason it can’t have two active IP addresses on two interfaces… but one should be disabled because you can’t have two interfaces that both define a default gateway.
Well, for one thing, we just got the Comcast connection a short time ago, and it was acting beautifully for the first couple of months. I think I might need to call Comcast to figure out why it’s not working as well now, but I dread having to talk to their customer support people.
Second, I (and the spouse) are rather hardcore WoW players, and we don’t like being without our connections since raiding with our guilds is one of our primary recreational activities. The two connections are meant to be a guarantee that we’ll never be without connectivity unless the power completely goes out. I know, kind of sad, but people spend money on a lot sillier things than that. And considering that it’s working as intended (Comcast gets wonky, I just head upstairs and fire up the other machine with Earthlink), or vice versa, I’m pleased with it.
A related question: if you have two NICs connected to two different networks, can both NICs be enabled and have an IP address active in the same computer at the same time? If so, how do you tell your apps which connection to use?
There is also such a thing as a dual WAN router. I have one made by Hotbrick. (or at least branded as such) If I was at home, I could tell you the model number. It is a router only, not a wireless router, but I have an outboard WAP which it plays nice with.
It can be set up to load share between the two internet connections(bandwidth amalgamation)but this can cause trouble with lots of internet applications beyond simple browsing, as you can appear to the outside world to have a split personality. (two IP addresses) I’m a lamer, so I have no idea if WoW would be happy with this or not. I’d guess not, though uTorrent seems to work well, so maybe? But you can also set it to a fail-back mode where if the primary WAN fails, it will use the secondary WAN connection.
Two NICs is by far the easiest solution. Just make sure that Windows doesn’t decide to automatically route. A possible problem is that both routers may assign you the same IP address; you’ll need to set up each router to assign different ranges - 192.168.x.x on one and 172.16.x.x (?) or 10.x.x.x on the other.
OTOH if you’re mates with the IT guys at work, you may be able to borrow an old Cisco router and have them set it up properly - if one of them’s studying for certification, they’d likely jump at the chance. You’ll need to get the loan documented, of course.
Each NIC will have its own IP address or addresses. Some NICs support teaming where they get joined together but that’s well beyond this thread.
Firstly there’s the Default Route - pretty obvious - but there’s also a parameter called the Metric, which is your rating of the connection. If the default route is sufficiently congested, the computer will look at the Metrics of the other connections and decide based on them.
And considering that it’s working as intended (Comcast gets wonky, I just head upstairs and fire up the other machine with Earthlink), or vice versa, I’m pleased with it.