Right now we use a T1 circuit which is split to provide voice bandwidth for our phones and the rest for Internet. We use several static IP addresses as well.

I am looking to add a second internet provider without disrupting any of our existing phone service OR the static IP's...possibly a cable connection or dry-loop DSL connection.

The question is how do I "tell" our computers here to use the new connection for Internet but continue to use the existing static IP address we have for VPN, etc?

Is this possible? Change the gateway?

Thanks

my suggestion would be just add another gateway(new connection) and then add the new network to each computer.

i wouldn't even know how to combine 2 ISPs into one network, if that's what you're trying to, but i can think of a few ways that i'd like to try.

but i think 2 networks would be much simpler. just customize each machine for where/what it needs to do.

-edit upon further thought, you ARE probably trying to support one network with two internets.
and i'll keep thinking about it

i guess i'm totally at a loss here. Right now our network is like this...T1 comes in, Adtran modem splits off data and voice channels. Data comes over to our SonicWall TZ270 into the WAN port...the SonicWall then routes the data out of a LAN port, and then over to our main backbone gigabit switch, and then off to all the subswitches and workstations. I guess my question is, in keeping all this intact, is how to add the new Internet connection into the network? Does it plug into one of the other ports on the SonicWall? Do I need a separate router?

Well that is not so hard if you use IAS or ISA and/or NAT Pool.
Without them its kinda complicated. Its all about default gateways however. If you are smart enough no additional setup needed to use 2 ISPs. Routers (recent) do support redundant ISP connections. You have to NLB using either routers or edge servers (from where the traffic go out). You van use Stonegate products (not sure whether they are available now). The easiest to use a router with wan ports (Cisco or similar).

there is also the possibility of using a desktop as a router(internet connection sharing)if it has 2 adapters, and put a router(LAN only) in-between the existing modem and stonewall thing(or wherever)plug one adapter to the modem, other to the router, then bridge the adapters.

kinda silly, i know, but there's many ways

-edit-3 bridged adapters & no router?maybe?

I can't put dual adapters in our many workstations and bridge...

We can't save any money by not paying our current company for the static IP's...our monthly bill is the same. However, it does cost more to add static IP's to a second ISP.

you only need one with 2 adapters. one adapter goes to same router as the rest of the workstations, the other adapter goes to new connection, bridge adapters, set-up ICS(sharing) on this one workstation to share new connection with the others.
i am over-simplifying on purpose.

Oh, I see what you're saying now. Maybe that's a possibility.

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