You could use a DUAL WAN Router (like MicroNet / Planet / HotBrick / etc)
There you should set up your Routing Rules, in order to use 1 connection or 
the other

Else, try PFSense (m0n0 based with Dual WAN), and tell us the result!!!

>From: "Gavin Pidgley" <gavin at gadago dot net>
>To: m0n0wall at lists dot m0n0 dot ch
>Subject: [m0n0wall] Dual WAN Ports
>Date: Fri, 24 Jun 2005 17:40:24 +0100 (GMT Daylight Time)
>
>
>Hi List,
>
>Just wondering if it is possible to have dual WAN ports with m0n0wall?
>What I basically want to acheive is to combine two adsl connections and in
>theory get double download/upload speeds with the two connections combined
>together. This would obvisouly have to be done via some form of load
>balancing. A similar product on the market is this
>http://www.broadbandbuyer.co.uk/Shop/ShopDetail.asp?CategoryID=48&ProductID=915&ShopGroupID=12
>but it does not have all the features such as 1:1 NAT that I use with
>m0n0wall.
>
>Anyone know if this is possible with m0n0wall at the moment or will a it
>be a feature in a future version?
>
>TIA
>
>Gavin

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